PROPOSED REVISION AND CONSOLDIATION OF:
PCC C-2–2015 X ASME PC (Revision of ASME PCC-2–2011) and PCC-2S-2015)
Repair of Pressure Equipment and Piping TENTATIVE SUBJECT TO REVISION OR WITHDRAWAL Specific Authorization Required for Reproduction or Quotation ASME Codes Codes and Standards Standards
A N A M E R I C A N N A T I O N A L S T A N D A R D
Two Park Avenue • New York, NY • 10016 USA
The requirements and recommendations recommendations established by the the Committee are not to be interpreted as approving, approving, recommending, or endorsing any proprietary or specific design or repair method, or as limiting in any way the freedom to choose any method of design or any form of repair that conforms to these requirements and recommendations. The Committee meets regularly to consider revisions, to develop new requirements and recommendations as dictated by technological development, Cases of the PCC Standards, and requests for interpretations. Only the Committee has the authority to provide official interpretations of these Standards. Requests for revisions, new rules, Cases of the PCC Standards, or interpretations shall be addressed to the Secretary in writing and shall give full particulars in order to receive consideration and action (see Submittal of Technical Inquiries to the Post Construction Standards Committees). to the Standard inquiries will be ASME formed an Ad HocProposed Task Grouprevisions on Post-Construction in 1993 inresulting response tofrom an increased
FOREWORD
for and generally accepted engineering standards forAt thethe inspection and maintepresented to theneed Committee for equipment appropriate action. The action of service. the Committee becomes effective only after ofrecognized pressure after it has been recommendation of confirmation bynance ballot of the Committee and approval byplaced ASME.inProposed revisions to the Standards approved by this Task Group, the Board on Pressure Technology Codes and Standards (BPTCS) formed the the Committee are submitted toCommittee the American Standards Institute (ANSI) and published Post-Construction (PCC)National in 1995. The scope of this committee was to develop and at http://go.asme.org/BPVCPublicReview to invite comments all interested persons. After public review and maintain main tain standa standards rds addressing addressing commo common n issues issues and from technologie techno logies s rel related ated to post-const post-constructio ruction n activities to work with other consensus committees in the development of separate, productfinal approval by ASME,and revisions are published in the next scheduled edition of the Standard. specific codes and standards addressing issues encountered after initial construction for equipment and piping covered by Pressure Technology Codes and Standards. The BPTCS covers nonnuclear boilers, pressure vessels (including heat exchangers), piping and piping components, pipelines, and storage tanks. The PCC selects standards to be developed based on identified needs and the availability of volunteers. The PCC formed the Subcommittee on Inspection Planning and the Subcommittee on Flaw Evaluations in 1995. In 1998, a Task Group under the PCC began preparing Guidelines for Pressure Boundary Bolted Flange Joint Assembly. In 1999, the PCC formed the Subcommittee on Repair and Testing. In 2002, the Subcommittee on Flaw Evaluation was dissolved and replaced by the Joint ASME/API Committee on Fitness for Service. Other topics are under consideration and may be developed into future guideline documents. The subcommittees were charged with preparing standards dealing with several aspects of the in-ser in-servic vicee inspec inspection tion and mai mainte ntenan nance ce of press pressur uree equ equipm ipmen entt and pip piping ing.. The Ins Inspec pection tion Planni Planning ng Standard provides guidance on the preparation of a risk-based inspection plan. Defects that are identified are then evaluated, when appropriate, using the procedures provided in the Fitness for Service. Finally, if it is determined that repairs are required, guidance on repair procedures is provided in the Repair of Pressure Equipment and Piping Standard. These documents are in various stages of preparation. None of these documents are Codes. They provide recognized and generally accepted good practices that may be be used in conjunction with Post-Construction Post-Construction Codes, Codes, such as API 510, API 570, and NB-23, and with jurisdictional requirements. The first edition of ASME PCC-1, PCC-1, Guidelines for Pressure Boundary Bolted Flange Joint Assembly, Assembly, wa wass appro approvedfor vedfor publica publication tion in 200 2000. 0. ASME ASME PCC-1– PCC-1–200 20000 wasappro wasapprove ved d by the Ame Americ rican an Nati Nationa onall Standards Standa rds Institute (ANSI) as an American American National Standa Standard rd on Novembe Novemberr 15, 2000. The first edition of ASME PCC-2, Repair PCC-2, Repair of Pressure Equipment and Piping, Piping, was approved for publication in 2004. This revision was approved by ANSI as an American National Standard on January 13, 2015.
Subsequent editions were published in 2008, 2011 and 2015. Starting with this 2018 edition, new editions are expected to be published on a four year cycle. The first edition of PCC-3, Inspection Planning Using Risk-Based Methods, was approved for publication in 2007. It was approved by ANSI as an American National Standard on October 4, 2007.
iv
PREPARATION OF TECHNICAL INQUIRIES INTRODUCTION The ASME Post-Construction Standards Committee will consider written requests for interpre and revisions of the rules content of this Standard and The new rules and tations develop recommendations if dictated by technologi-cal development. Committee’s requirements activities in this
regard are limited strictly to interpretations of the rules content or to the consideration of revisions to the present rules requirements and recommentations on the basis of new data or technology. As a matter of published policy, ASME does not “approve,” “certify,” “rate,” or “endorse” any item, construction, proprietary device, or activity, and, accordingly, inquiries requiring such consideration will be returned. Moreover, ASME does not act as a consultant on specific engineering problems or on the general application or understanding of these rules requirements and recommendations . If, based based on the inquiry information submitted, it is the opinion of the Committee that the inquirer should seek professional assistance, the inquiry will be returned with the recommendation that such assistance be obtained. An inq inquir uiry y that that doe doess not prov providethe idethe inform informatio ation n needed needed for theCommitte theCommittee’ e’ss full full und unders erstand tanding ing will be returned.
REQUIREMENTS Inquiries shall be limited strictly to interpretations of the rules content of this Standard or to the consideration of revisions to the present rules requirements and recommendations on the basis of new data or technology. Inquiries shall meet the following requirements: (a) Scope. Involve a single rule requiremnent or recommendation or those closely related rules in the scope of the standard. An inquiry letter concerning unrelated subjects will be returned. (b) Background. State the purpose of the inquiry, which may be be either to obtain an interpretation of rules a requirement or recommendation of this Standard, or to propose consideration of a revision to the present rules content. Provide concisely the information needed for the Committee’s understanding of the inquiry, being sure to include reference to the applicable Part, Article, Edition, Addenda, paragraphs, figures, and tables. If sketches are provided, they shall be limited to the scope of the inquiry. (c) Inquiry Structure (1) Proposed Proposed Question Question(s). (s). The inquiry shall shall be stated in condensed condensed and precise precise question format, omitting superfluous background information, and, where appropriate, composed in such a way thatshould “yes” be or “no” (perhaps provisos) would be an acceptable reply. The inquiry statement technically and with editorially correct. (2) Proposed Proposed Reply( Reply(ies). ies). Provide a proposed reply stating what the inquirer believes that the standard requires. If in the inquirer’s opinion, a revision to the standard is needed, recommended wording shall be provided to information justifying the change. in addition
SUBMITTAL Inquiries shall be submitted through the online Interpretation Submittal Form. The form is accessible at http://go.asme.org/InterpretationRequest. If the Inquirer is unable to use the online form, the inquiry typewritten form; however, legible handwritten inquiries will be considered. They shall include the name and mailing address of the inquirer, and may either be sent by email to
[email protected], or by mail to the following address: Secretary ASME Post-Construction Two Park Avenue New York, NY 10016-5990 v
ASME PCC-2–2015
Part 1
REPAIR OF PRESSURE EQUIPMENT AND PIPING
, piping, pipelines and associated ancillary equipment
PART 1 SCOPE, ORGANIZATION, AND INTENT
1 SC SCO OPE
(e) Part 5 covers examination and testing methods and techniques.
This Standard provides methods for repair of equipment and piping within the scope of ASME Pressure Technology Codes and Standards1 after they have been placed in service. These repair methods include relevant relevant design, fabrication, examination, and testing practices and may be temporary or permanent, depending on the
3 IN INTTEN ENT T 3.1 Genera Generall
This standard does not purport to This Standard provides technical information, proceaddress all of the safety concerns, if dures, and recommendations fortorepair methods that any, with its use. Itbeisrecognized the wereassociated determined by consensus and generally gene rally accep accepted ted good engineerin engin eering g practice. practi ce. Where Wher e responsibility of the user of this equipmentto repair is subject to jurisdictional regulation, standard establish appropriate jurisdictional approvals approvals may be required. safety and health practices, and 3.2 Defini Definitions tions determine the applicability of may,, shall shall,, and should should are The words may wordslimitations and used in the repair regulatory prior to are use.
circumstances. The methods provided in this Standard address the repair of components when repair is deemed necessary based on appropriate inspection and flaw assessment. assessment. These inspection and flaw evaluation methods are not covered in this Standard, but are covered in other postconstruction codes and standards. Only technical procedures and information are provided; vide d; admin administra istrative tive or policy requirem requirement entss are outsid outsidee of the scope of this Standard.
articles of PCC-2 and they have the following intent: may: indicates an action that is permitted, but not may: indicates required. shall: an action that is mandatory. It indicates an action shall: an that is an essential element of the repair method that cannot be eliminated.
2 ORGANI ORGANIZA ZATIO TION N This Standard is divided into five Parts. (a) Part 1 covers the scope, organization, and intent and is applicable to all articles in this Standard. Table 1 provides guidance for the applicability of repair methods listed in this Standard. (b) Part 2 covers repair methods and techniques that include the use of welding, brazing, soldering, or other methods involving metal deposit. (c) Part 3 covers mechanical repairs, with or without sealant, seala nt, such as bolted clamps or fixtures fixtures and includes all repair methods not covered in Part 2 or Part 4. (d) Part 4 cove covers rs repairs repairs using nonmetallic nonmetallic means, such as nonmetallic liners and wraps, and bonding (e.g., jo in in g by ep ox y) , in cl ud in g bo nd in g of me ta ll ic components.
should: an action that is not mandatory. It indicates an should: an action that when performed, is generally considered to be good practice; however, however, there are some circumstances when the action is not appropriate or required, so the word should is used used to pr prov ovid idee fl flex exib ibili ility ty fo forr the the artic article le to cover cov er a broad broad range range of cir circum cumstan stances ces.. It is notmandator notmandatory y unless so specified by others in the application of these articles.
3.3 Administrative Requirements For administrative requirements such as inspection, documentation, and quality control, the user is referred to an applicable post-construction code and to the jurisdictional requirements. In the absence of an applicable post-const post-c onstruction ruction code or juris jurisdiction dictional al require requiremen ments, ts, the owner of the pressure equipment or piping should
1
Equipment andand piping within the scope of ASME Pressure Technology Codes Standards includes piping (including pipelines) and piping components (such as valves), boilers, pressure vessels (including heat exchangers), and storage tanks.
establish establis h the adm adminis inistra trative tive requir requireme ements nts.. A post-const post-c onstruction ruction code is one that pro provide videss requ require iremen ments ts and guida guidance nce for inspection inspection and/or repair repair of equipment equipment 1
Part 1
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ASME PCC-2–2015
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2
ASME PCC-2–2015
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3
Part 1
Part 1
Editing Note: italicize this phrase
ASME PCC-2–2015
3.8 Code R Refere eferences nces
after it has been placed in service, and may include the references to original code of construction. Examples of post-construction codes include NB-23, API 510, API 570, and API 653.
Reference to specific codes is generally avoided in this Standard because the equipment or piping could have been constructed in accordance with a number of differen entt cod codes. es. Where Where suc such h a refer referenc encee is prov provide ided, d, it is genergenerally the intent to include, by reference reference,, a specific technical provision.
3.4 Applicati Application on
(a) Users of the articles contained in this Standard are cautioned caution ed that that these these article articless ha have ve been been dev develo eloped ped gen genererically and are recommended for general applications. They The y may may not necess necessari arily ly be suitab suitable le for all app applica lication tions. s. Precautionary considerations are provided, but should not be considered all inclusive. Sound engineering practices and judgment should be used to determine the applicability of a specific method or part of a method to a specific application. Each repair should be subject to an appropriate review by qualified personnel, and this review should consider subsequent deterioration of the repaired component. (b) Some Additional limitations and considerations are contained in section 2 of the individual articles.
3.9 Wel Welding ding Requirements for welding, including qualification of welding procedures, welders, and welding operators should generally follow an applicable code of construction or an applicable post-construction code, except when otherwise specified herein.
3.10 Allowabl Allowable e Stress Calculations involv Calculations involving ing the allowable allowable stress use the allowa allo wable ble stressfrom stressfrom the ori origin ginal al code code of constr constructi uction on or an applicable post-construction code, unless otherwise specified in specific articles.
3.5 Alternat Alternative ive Use While Whi le this this Stan Standar dard d cover coverss repai repairr of equ equipm ipmen entt within within
3.11 Examinatio Examination n
the scope of ASME Pressure Technology Codes and When qualifications of examiners, methods examiengineering practices and judgment The phrase refersof to refers Standards, it may be used on equipment constructed in technical judgments made by knowledgeable engineers or nation, extent of examination, and acceptance criteria accordance with other Codes and Standards. are not experienced specified, they should the requirements subject matter experts in thefollow application of repair of an applicable code of construction or an applicable 3.6 Articles’ Articles’ Indepe Independenc ndence e practices. Engineering judgments shall shall be consistent with post-construction code. Individual articles in this Standard may be used inde-
good engineering practices, and such judgments shall never
pendently of other articles, except when otherwise be used to overrule requirements or specific 3.12mandatory Records Records noted. However, this Part (Part 1) applies to all articles prohibitions of this The standard. in this Standard. owner should keep records that document the repair. Specific requirements for documentation are not 3.7 Repair Repair Life Life provided in this Standard. The owner should retain recMany of th e repair techniques included in this (c) ordsThe that repair complymethods with applicable applica ble jurisdictional and provided in the articles in Standard are considered to be permanent, intended to post-construction code requirements. Documentation this Standard are applicable to a variety of remain in place for the life of the repaired component. may include such items as a description of the condition mechanisms. Examples damage Others may only be suitable for short-term service, and damage that required attention and its cause, repairofprocedures should be replaced with a more permanent repair at that were used, photos prior to and after the repair, the an appropriate opportunity. The anticipated life of mechanisms may beand found in heat API Recommended examination procedures procedur es records, treatmen treatment t recPractice 571. Other applications of repair for the a repair depends on many circumstances, and ords, test records, and the names of the persons/firms mechanisms are provided for in could include consideration of risk. As such, this damage performing the repair and examination and their certifiarticles. Standard does not classify repair methods as permanent individual cation. The documentation forms part of the history of or tempo-rary. Rather, technical considerations that the pressure component and should be retained as long affect the expected life of the repair are stated in the as it is relevant. individual articles.
4
ASME PCC-2–2015
3.7 Structural Structural Stability Stability at Cutouts Cutouts
Part 2 — Article 2.1
be repaired. Thicker pipe or tube inserts may be used, provided they meet the requirements of para. 4.1.5.
Consideration should be given to structural stability and possible distortion of the unsupported plate edges of large openings (cutouts) in the vessel she shell. ll. An assess assess-ment should be made for the need of temporary supports around the unsupported edges of such openings during removal of the shell section to be replaced with
4.1.3 Forming Strains in C Carbon arbon and Low Low Alloy (15) Steels. Carbon Carbon steel and low alloy steel insert plate platess should be heat treated (stress relieved, normalized, or quenched and tempered, if appropriate) subsequently when the resulting extreme fiber elongation during cold
an insert insert plate. The e assessme asse ssment shall conside consider all compoloading loading conditions that Th may occur onntthe vessel andrthe nent during the repair, including structural stability of vessels during PWHT.
formin forming g is more more than than 5%, as determ determine ined d by thefollowing thefollowing formulas: (a) For single curvature shells (cylinders) Percent extreme fiber elongation
3.8 Insert Plates Plates With Nozzles Nozzles The nozzle/man nozzle/manwa way y reinforc reinforcemen ementt in inse insert rt plates with nozzles shall meet the design requirements and we weld ld details details of theappli theapplicab cable le cod codee of constr constructi uction on for the pressure component. The minimum diameter of insert plate with a nozzle shall be the larger of the following: (a) for all nozzle/manway assemblies, the diameter of the nozzle/manway penetration plus the width needed for nozzle reinforcement and any edge bevels (b (b)) for nonpostweld heat-treated carbon and low
p
R f 50t 50t 1− ,% R f Ro
(b) For double curvature (heads and spherical shells), Percent extreme fiber elongation
p
R f 75t 75t 1− ,% R f Ro
where R f final centerline radius, mm (in.) Ro original centerline radius, mm (in.). (Radius equals infinity for flat plate.) p
p
p
alloy steel nozzle/manway assemblies, the diameter of the insert plate needed to maintain a minimum distance of 150 mm (6 in.) between the nozzle attachment weld and the nearest edge of the insert plate butt weld. However, the diameter of the insert plate for nozzles having an outside diameter 300 mm (12 in.) or smaller need not be larger than 2 times the outside diameter of the nozzle. (See also Figs. 2 and 3.)
t plate thickness, mm (in.) As an alternative, the rules of the original code of construction may be used.
4 FABRIC FABRICAT ATION IONfor which the nozzle to butt
4.1.5 Alignment at Edges of Insert Plate. The alignment at edges of the insert plate butt weld shall be such that the maximum offset is within the limitations of the applicable code of construction for the pressure component. If the insert plate thickness exceeds these limitations, the edge(s) of the insert plate shall have a tapered transition having a length not less than 3 times the offset between the adjacent surfaces of abutting sections.
4.1.4 Forming Strains iin n Other Materials. Coldforming strains (e.g., from bending) in materials other than carbon and low alloy steel shall not exceed the limitations in the applicable code of construction without a subsequent heat treatment.
patch (shell) weld is not postweld heat treated 4.1.1 Edge Be Bevels. vels. Edge bevels bevelsthe in the ins insert ert plate before or after assembly and in the pressure pressure compone component nt may be prepared prepared by is welded into the shell,
4.1 Cutting Cutting and Forming Forming
thermal cutting, arcbe gouging, machining, or grinding. The method should appropriate for the material and welding process(es) used. All edges prepared for welding shall be examined to the requirements of the applicable code of construction or post-construction code for the pressure component being repaire repaired. d. All unacceptable indications shall be repaired to the requirements of the applicable code of construction or post-construction code.
4.2 Wel Welding ding 4.2.1 Weld Welded ed Joints. The weld between between the inse insert rt plate and the existing pressure componen componentt shall be a full penetration butt weld. Where possible, double-welded butt joints should be used.
4.1.2 Forming. Forming. Forming Forming the inser insertt plate to the desired shape may be accomplished by any process that does not impair the properties of the plate material. It may be rolled or pressed to the proper curvature such that it conforms to the curvature of the vessel shell after it has been installed and welded into the vessel shell,
4.2.2 Stren Strength gth of Welded Joint Joints. s. The w welded elded joints joints (weld metal (weld metal and hea heat-a t-affe ffecte cted d zones) zones) shall shall meet meet the min min-1 imum strength and toughness requirements and other require requ iremen ments ts in the curren currentt edition of the applic applicable able code of construction for the pressure component.
pipe, or tube. For pipe or tube inserts, the insert may also be cut from another piece of pipe or tube of the same diameter and thickness as the pipe or tube to
Matching strength filler be metal noted in the AWS 5.X filler metal specifications should usedasfor welding pressure components.. Use of as-de nents as-deposited posited weld metal with substantia substantially lly greater strength streng th is not recommended. recommended.
1
7
Part 2 — Article 2.1
ASME PCC-2–2015
Fig. 3 Intersectin Intersecting g “Doghouse” “Doghouse” TType ype Insert Insert Pla Plate te Butt Weld (With or Without Nozzle/Manway) With Shell Butt Weld in Vessel Vessel Shells and Heads Heads
Fig. Fig. 2 Flush Flush Insert Insert Plate Plate (Wit (With h or Without Without Nozzle/Manway) With Its Butt Weld Intersecting Existing Butt Weld in Shells or Heads
Note (1) Note (2) Note (1) Note (3)
Note (2) Note (4)
Note (3) Note (4)
Note (3)
Note (5)
Note (5) Note (2)
NOTES: (1) Exis Existing ting butt weld in vessel vessel shell or head. (Fig. 3 shows butt weld in a cylindrical shell.) (2) Lengt Length h of cut in shell butt weld, weld, 150 mm (6 in.) minimum minimum on each side of intersecting insert plate butt weld. (3) Inser Insertt plate butt weld. weld. (4) Cut exis existing ting shell shell butt weld to 150 mm (6 in.) minimum on each side of intersecting insert plate butt weld and bevel edges (or arc gouge edges) to the desired edge bevels. Reweld after completion of insert plate butt weld. Full RT or UT, or MT or PT both sides of new weld. (5) For nonpos nonpostweld tweld heat treated treated carbon and low allo alloyy steel nozzle/manway assemblies, 150 mm (6 in.) minimum between the toe of the nozzle fillet weld and the nearest edge of the insert plate butt weld (see para. 3.8).
NOTES: (1) Exis Existing ting butt weld in vessel vessel shell or head. (Fig. 2 shows butt weld in a cylindrical shell.) (2) Thirty deg min minimum imum angle. (3) Full RT or UT, or MT or PT both sides of existing butt weld, 100 mm (4 in.) min. each side of intersection with insert plate. (4) Inser Insertt plate butt weld. Full RT or UT, UT, or MT or PT both sides of weld. (5) For nonpos nonpostweld tweld heat treated treated carbon and low alloy steel nozzle/manway assemblies, 150 mm (6 in.) minimum between the toe of the nozzle fillet weld and the nearest edge of the insert plate butt weld (see para. 3.8).
See para. 3.8.
8
ASME PCC-2–2015
Part 2 — Article 2.3
Article 2.3 Seal-Welded Threaded Connections and Seal Weld Repairs can 1 DESCRI DESCRIPT PTION ION
the existing system, the ability to isolate the connection while the plant is still running, personnel exposure to the system contents, and the consequences of an unscheduled plant shutdown. Also, without attention to the details and QA/QC requirements in this Article, seal-welded threaded connections are prone to cracking and leakag leakage. e. Upo Upon n carefu carefull evalu evaluatio ation n of these these consid considera era-tions, tion s, it may may be conclu concludedthat dedthat a more more appro appropri priate ate action action is to replace the component(s) containing the threaded connections.
1.1 Introduction Introduction Where piping systems, pressure vessels, and process equipment are assembled by threaded connections, the mechanical seal of standard tapered pipe threads may be sufficient for many industrial applications. However, However, some systems handling fluids at high temperatures or high pressures; fluids that are flammable, toxic, or reactive; or fluids requiring very low leak rates, may not rely solely on threaded joints for leak tightness.
2.4 Potential Contaminants
1.2 Seal Welds Welds
For repair of leaking threaded connections, the original thread sealant compound, thread lubricant, and process fluid contamination can make seal welding difficult and result in cracking of welds.
When the convenience of a threaded connection is desired, and the reliable seal of a welded connection is required, a seal-welded threaded joint is sometimes used. Seal welds are applied after the threads are engaged. The mechanical strength of the joint is provided by the threads, while the seal weld provides leak tightness. might
2.5 Welding an and d Material Considerations Considerations For all seal welds, careful evaluation of the joint is needed. Some Some threaded connections ar aree made of materials that are difficult to weld, such as cast iron. Joints may require high preheat, stainless or chrome-moly welding fillers, or other special welding requirements, based on the materials of construction and service.
1.3 How Seal Seal Welds Welds Are Used Seal welds are used in two different ways. Some are installed in new construction, as part of the original design. Other seal welds are used after construction, as a maintenance procedure to seal threaded connections that have have leaked. leaked. Finall Finally y, older plan plants ts may hav havee threade threaded d connections that were permitted in past specifications
It is essen essential tial that that coa coating tings, s, includ including ing zin zincc galva galvaniz nizing ing,, be removed from the weld zone before welding. Recoat-
but need to be upgraded today by seal welding as part of an integrity management program.
ing the joint joint area, area, afte afterr weldin welding g and testing testing are are com comple plete, te, shall be considered.
2.6 Remov Removal al of Coatings Coatings
2.7 Wel Welding ding Effect on Adjacent Adjacent Componen Components ts
2 LIMIT LIMITAT ATION IONS S
In seal welding of threaded threaded connectio connections, ns, consi considerderation shall be given to the possible damaging effects of welding on adjacent components, such as soft seats in threaded valves.
2.1 Additiona Additionall Requirements Requirements Part 1 of this Standard contains additional requirements and limitations. This Article shall be used in con junction with Part 1.
2.2 Speci Special al Considerati Considerations ons Outside of Scope
3 DES ESIG IGN N
Seal-welded repairs conducted on-line, or to systems containing hazardous materials, may require special considerations that are outside the scope of this Article.
3.1 Appli Applicabl cable e Codes For repair of original seal welds, consult the original code of construction, or applicable post-construction code. The requirements specified in paras. 3.1(a) and 3.1(b) are from the ASME BPVC Section I, ASME B31.1, and ASME B31.3, but may be successfully used on any seal-welded joint repair.
2.3 Considera Consideration tion of Hazards Hazards Before seal welding an existing threaded connection, consideration should be given to the potential hazard of 17
Part 2 — Article 2.3
ASME PCC-2–2015
(a) The seal weld shall only be used to provide the hermetic seal, not the mechanical strength to the joint. (b) All of the remaining exposed threads (if any) shall be completely covered with weld metal.
(a) remove remove as much old thread sealing joint compound as possible. A wire brush, grinder, or torch may be needed. (b) expect the likelihood of porosity in the first pass, caused by burning joint compound or trapped fluid. (c) gr grind ind out any porosi porosity ty or other other def defect ectss and rewe reweld. ld. Repeat as necessary until weld is leak tight.
3.2 Application Application to Existing Existing Joints For repair of leaking threaded connections that are not originally seal welded, it may not be possible to meet the conditions of para. 3.1(a) or 3.1(b). Seal welds applied over over existing threaded threaded joints may be less rreliable eliable than new construction, so the user must evaluate the safety and reliability of each application individually.
5 EXAMIN EXAMINAT ATION ION 5.1 Techniques and Methodology Visual examination (VT) is the most common examination technique used for thread seal welds. Magnetic particle examination (MT) or liquid penetrant examination (PT) may be required by the applicable code, or may be used to provide greater assurance of leak tightness. The methodology shall be in accordance with the applicable code of construction or post-construction code.
3.3 Joint Reasse Reassembly mbly If the joint is disassembled, it shall be reassembled without the use of any tape, lubricants, or joint compound.
3.4 Two Pass Pass We Welds lds The use of two pass welds over all exposed threads shall sha ll be con consid sider ered. ed. Two pas passs we welds lds incre increase ase the reliab reliabilility of the joint.
6 TE TEST STIN ING G 4 FAB FABRIC RICA ATION TION
6.1 Initi Initial al Service Testin Testing g
4.1 Cleanin Cleaning g Remove the system from service, and drain the process fluid. Make the system safe for hot work. This may be do done ne by pu purgi rgi ng with wi th st ea eam, m, nitro ni tro gen , or other ot her inert gas.
5.1 Visual Examination
4.2 Cleanin Cleaning g of Joints All thread seal welding shall be Prior to seal w weldin elding, g, joints joints shall shall be clean cleaned ed to rem remove ove examination (VT). all surface contamination.
For most applications, an initial service leak test, in which the joints are examined for leakage when the system is returned to service, is sufficient. Where the possibility possib ility of leakage leakage during an initial service leak test is unacce unacceptab ptable, le, additio additional nal NDE, NDE, or a hydro hydrostat static ic or pneumatic leak test should be performed prior to placexamined by visual ing the system in service.
5.2 Magnetic Particle and Liquid Penetrant Examination 6.2 Leak TTestin esting g 4.3 Welding Qualifications Magnetic particle examination (MT)Ifor liquidassurance penetrant greater of leak tightness is required prior Welders andexamination welding procedures shall be qualified (PT) may be used to provide greater to service, a preservice leak test may be used. Options per ASME BPVC Section IX, or other applicable code of include bubble testing, pneumatic testing, and hydroof leak tightness as applicable. construction orassurance post-construction code. static testing testing.. 5.3 Acceptance Standards 4.4 Fatigue Considerations Acceptance criteria shall be in accordance with the NOTE: The user is cautioned cau tioned to cons consider ider any hazard hazardss that migh mightt For conne connectio ctions ns subjec subjectt to vib vibrat ration ion or fatigue fatigue,, con consid sid- be associated with the test medium (e.g., toxicity, toxicity , flammability, flammability , applicable code of construction or post construction code. eration shall be given to removal by grinding of all reactivity reactiv ity,, explo explosibil sibility), ity), pressure pressure level of fluid, fluid, and coinci coincident dent stress level/temperature of the components. exposed threads prior to seal welding.
4.5 Prior Seal Seal Welded Welded Joints For repair or replacement of original seal welds (a) if installing replacement pipe or fittings, do not use thread sealant compound or lubricant (b) for repair without disassembly, disassembly, the integrity of the old seal weld should be inspected visually to determine if it should be completely removed
7 REFE REFEREN RENCE CES S ASME Boiler and Pressure Vessel Code, 2004 Edition, Section I — Power Boilers; Section IX — Welding, Brazing, and Fusing Qualifications ASME B31.1, Power Piping ASME B31.3, Process Process Piping
4.6 Welding Existing Connections Connections Without
Publisher: The American Society of Mechanical
Disassembly For seal welding original threaded connections without disassembly, disassembly,
Engineers (ASME), Two Park Avenue, New York, NY 1001610016-599 5990; 0; Order Order Depart Departmen ment: t: 22 Law Drive, Drive, P.O. Box 2900, Fairfield, NJ 07007-2900 (www.asme.org) 18
ASME PCC-2–2015
Article 2.5 Welded Lip Seals the coursePDF of preparation.) See(In attached file: 14-1093.pdf
23
Part 2 — Article 2.5
ASME PCC-2–2015
Part 2 — Article 2.6
Fig. Fig. 1 Type A Slee Sleeve ve Sleeve
Carrier pipe Longitudinal weld seam
Carrier pipe
Fillet welds
Gap
Groove Weld optional No Backing Strip
Backing Strip With No Relief Groove
Backing Strip and Relief Groove
25
Overlapping Side Strip
Part 2 — Article 2.6
ASME PCC-2–2015
Fig. Fig. 2 Type B Slee Sleeve ve End fillet weld Sleeve
End fillet weld
Carrier pipe Longitudinal weld seam (butt weld only. Overlapping side strip not allowed.) Carrier pipe
No Ba Backing St Strip
Backing Strip With No Relief Groove
Backing St Strip and Relief Groove
Fig. Fig. 3 Welde Welded d Spl Split it Sleev Sleeve e for U Use se Over a Girth Weld
Bulge in Sleeve to Fit Over Existing Circumferential Weld
26
Overlapping Side Strip (Not Allowed)
ASME PCC-2–2015
2.9 Welding Welding Welds shall be installed by qualified welders in accordance with qualified procedures reflecting actual field conditions. Filler Material 2.10 Weld Weld Filler Metal Metal If a hardenable filler material is used between the sleeve and carrier pipe, it shall be compatible with the intended application. The material shall be suitable for theservice theserv ice temper temperatu atureand, reand, for TypeB sle sleev eves,compa es,compatiti ble with the fluid. Filler material may be applied prior to sleeve installation or pumpe pumped d in between the slee sleeve ve and carrier pipe annulus after the sleeve is in place.
3 DE DESI SIGN GN
may be left as is or chamfered
Part 2 — Article 2.6
(a) A complete fillet weld if the sleeve thickness is less than or equal to 1.4 times the nominal carrier pipe wall thickness, as shown in Fig. 4. (b) If a Type B sleeve is thicker than 1.4 times the nominal carrier pipe wall thickness, the circumferential endss of theType end theType B sleeveshoul sleeveshould d be cha chamfe mfere red d at app appro roxximately 45 deg, down to 1.4 times the carrier pipe nominal wall thickness plus the gap spacing, as shown in Fig. 5. The toe of the weld on the carrier pipe shall smoothly transition from the carrier pipe to weld in order to minimize the level of str stress ess intensification intensification.. The included angle between the weld toe and the carrier pipe shall not create a sharp notch, and defects such as undercut are not allowed.
3.1 Ty Type pe A Sleeves Sleeves Type A sleeves shall be fabricated or manufactured from steel meeting the mater material ial spec specificatio ifications ns of the construction code, and should have a thickness equal to at least two-thirds the thickness of the carrier pipe. The carrier pipe longitudinal stresses shall meet the requirements of the applicable construction code.
3.6 Exter External nal Pressur Pressure e External pressure loading of the pipe within Type B sleeves should be considered by the engineering design. Fitting the sleeve as tightly as possible to ensure load transfer from the pipe to the sleeve should minimize the annulus volume. If this is not possible, the annulus volume should be filled with hardenable filler material
3.2 Ty Type pe B Sleeves Sleeves Type B pressure containing sleeves shall have a wall thickness equal to or greater than the wall thickness required for the maximum allowable or,, 0.80 design pressure or if required by the engineering design, the full equivalen equivalentt strength of the pipe being repaired. For tight-fitting sleeves, the engineering design shall be based on the 1.00 of the carrier pipe. A longitudinominal wall thickness nal weld joint efficiency factor of 0.8 shall be applied when calculating the required thickness unless the weld is 100% examined by ultrasonic examination, in which case a joint efficiency factor of 1.0 may be applied. If the Type B sleeve sleeve is in inten tended ded to prov provide ide axial axial reinf reinfor orcem cemen ent, t, such as at a defective girth weld, it shall be designed
(see para. 2.9) or the pressure should be balanced by hot-tapping the pipe under the sleeve. A vent or drain may be provided in the design. If the annulus is to be left unfilled, it should be verified that the stagnant fluid between the sleeve and the carrier pipe will not cause corrosion.
3.7 Exter External nal Damage Damage If ext extern ernal al d dama amage ge is repa repaire ired d wit with h a Type A or Type B sleev sleeve, e, the dam damage age sha shall ll be fill filled ed with with a har harde denab nable le fill filler er material with compressive strength adequate to transfer the load to the sleeve. The use of a hardenable material should be applied to fill voids or cavities present between the Type B sleeve and the carrier pipe.
3.4 Sleeve Sleeve Dimensions Dimensions Types A and B sleeves shall be at least 100 mm (4 in.) long and extend beyond the defect by at least 50 mm (2 in.).
3.8 Cyc Cyclic lic Oper Operation ation (a) If the system is subjected to greater than 400 pressuree cyc sur cycles les,, where where the cha change nge in press pressur ure, e, durin during g a cyc cycle, le, exceeds excee ds 20% of the design pressure pressure,, then a detailed fatigue analysis of the component, considering fit-up of the sleeve to the inner pipe, shall be performed in accordance accor dance with API RP 579/ASME 579/ASME FFS-1. (b) If a Type B sleeve is subjected to changes in temperature where the difference in mean metal temperature between the sleeve and inner pipe is less than 100°F and the number of cycles is less than 200, then a fatigue analysis is not required, otherwise a detailed fatigue evaluation of the component, considering fit-up of the sleeve to the inner pipe, shall be performed in accordance with API RP 579/ASME FFS-1.
3.5 Ty Type pe B Sleeve Sleeve Fillet Welds Welds The fillet weld leg size for circumferential end welds for a Type B sleeve shall be as follows:
3.9 Restr Restraint aint of Pipe Bulging Bulging Local wall thinning or damage defects, such as dents, weaken the carrier pipe and typically bulge outward
to carry axial and bending loads acting at the sleeve location.
3.3 Pressure Pressure Design Design Thepressur Thepres suree de desig sign n cal calcul culatio ations ns of theapplic theapplicabl ablee conconstruction code shall apply for calculating the required sleeve thickness. Sleeve material and allowable design stress stress shall complywith the applic applicable able constructio construction n code requirements. Corrosion allowances applied shall be in accordance with the engineering design.
27
Part 2 — Article 2.6
ASME PCC-2–2015
Fig. 4 Ty Type pe B Sleeve Fillet Fillet Weld Weld Size for Sleev Sleeve e Thickness Thickness Less Than Than or Equal to 1.4 Times the Carrier Pipe Thickness
Type B sleeve
T s 1.4 1.4 T T p
Gap
G T s + G
Carrier pipe
T p
requ re m n mum
G = = gap
T p = carrier pipe wall thickness T s = Type B sleeve wall thickness
nomimal Fig. 5 Type Type B Sleeve Sleeve Fillet Weld Weld Size for Sleeve Thic Thickness kness Greater Greater Than 1.4 Times the Carrier Carrier Pipe Thickness Thickness
Optional chamfer T s 1.4 1.4T T p p
Type B sleeve
1.4T 1.4 T p
G
Gap
1.4T 1.4T p + G T p
Carrier pipe
required minimum
G = = gap
T p = carrier pipe wall thickness T s = Type B sleeve wall thickness
nominal prior to failure under increasing pressure. The effectiveness of repair sleeves relies on their capability to restrain the outward bulging of a pipe defect prior to its failure. The design shall consider if it is necessary (a) to use a har harden denabl ablee filler filler mat materi erial al (ep (epoxy oxy or equivequivalent) under the sleeve to fill the voids when the defect is external (b) to reduce the line pressure at time of installation
the design and application of both Type A and Type B sleeves.
4 FA FABRI BRICA CATIO TION N 4.1 Inst Install allation ation For install installatio ation n of a Type A or Type B sleeve sleeve,, the entir entiree circum circumfer ferenc encee of thecarrier thecarrier pip pipee in thearea to be co cover vered ed by the sleeve shall be cleaned to bare metal. If hardenable fill material is to be used, the filler shall be applied to all indentations, pits, voids, and depressions. The sleeve shall sha ll be fit fitted ted tigh tightly tly aroun around d thecarri thecarrier er pip pipe. e. Mec Mechan hanica icall clamping by means of hydraulic equipment, draw bolts, or other devices may be used to ensure fit. A “no gap” fit should generally be achieved; however, a radial gap of up to 2.5 mm (3 ⁄ 3322 in.) maximum may be allowed. For sleeves with welded ends, weld size and welder technique adjustments, such as buttering passes, may be required if the gap is excessive.
3.10 Type Type A Sleeve Sleeve Filler Material Material For Type A sleeves, it is necessary to achieve intimate contact between the pipe and the sleeve at the location of the defect being repaired and an appropriate filler material should be used to ensure that the sleeve provides the desired pressure load reinforcement.
3.11 Differential Thermal Expansion Expansion Differential Differ ential thermal expans expansion ion between between the carrier pipe and the reinforcing sleeve shall be considered in 28
ASME PCC-2–2015
Part 2 — Article 2.6
Welding Procedures and Welder Qualifications 4.2 Filler Material Materialss
(b) the risk of forming an unacceptably hard heataffected zone due to base metal chemistry of the sleeve and pipe materials (c) possible burn-through of the pipe
If a filler material material is used between between the pipe and slee sleeve, ve, care shall be exercised to ensure that it does not extrude into the weld areas. Burning of the filler material during welding will compromise the quality of the weld. Excess Excess Welding procedures, welders and filler material shall be removed prior to welding. Pumping filler materialoperators into the annulus the sleeve has welding shall after be qualified
4.7 Wel Weld d Procedure Procedure The weld procedure, including preheat and postweld heat tre treatme atment nt requ requirem irement ents, s, and welder welder,, or weld welding ing operators, opera tors, shall be qualifi qualified ed under the applicabl applicablee code of construction or post-construction code.
been welded in place eliminates thistoproblem, provided in accordance with current post the annular gaps are large enough allow the filler to construction code. If not otherwise flow into all voids.
specified, ASME BPV Code Section
5 EXAMINATI EXAMINATION ON
4.3 Leaking Lea Defects Defects IXking shall be used for procedure and For aperformance leaking defect, qualification. the defect area shall be isolated prior to welding. For lines with flammable contents, the Guidance for preheat and/or sleeve shall be purged with nitrogen or other inert gas postweld heat treatment, and for to prev preven entt the formati formation on of a com combus bustibl tible e mix mixtur tureeinund under er service welding, as applicable, shall the sleeve.
5.1 Visua Visuall Examination Examination All sleeve fit-ups shall be inspected prior to welding. Welds shall be visually examined.
5.2 Ty Type pe A Sleev Sleeves es
be taken from the applicable code of construction post construction If circumferential fillet end welds are made, the code.
Fo Forr Typ ypee A sl slee eeve ves, s, the the weld weld root root area area sh shal alll be visu visual ally ly examined during welding to verify proper penetration and fusion. The longitudinal welds shall be liquid penetrant, tran t, magn magnetic etic parti particle, cle, or ultrasonical ultrasonically ly examined examined after completion.
durin during g the fin final al clo closur suree we weld ld sha shall ll be mad made. e. The we weldi lding ng procedures for the circumferential fillet welds shall be suitab suitable le for themateri thematerials als and con conditi ditions ons of we weldld-coo coolin ling g severity at the installed location in the piping or pipelines, in accordance with the code of construction or post-construction code. A low hydrogen welding techThe For firstlongitudinal pass and welds without nique should be used. final pass of backing strips, seethe para. 4.5. If the circumferential circumferen tial welds are not made, Type A, the longitudinal seams may consist of a groove butt weld or fillet-welded lap joint, as shown in Fig. 1.
5.3 Ty Type pe B Sleev Sleeves es For Type Type B sleeves, the carrier pipe base material shall be ultrasonically examined for thickness, cracks, and possible possib le lamination lamination in the are areaa where where the circ circumfer umferentia entiall welds are to be applied. Sufficient wall thickness shall exist to prevent burn-through. If a backing strip is not used use d under under the lon longit gitudi udinal nal we weld, ld, the area und under er it shall also be ultrasonically ultrasonically examined prior to welding. welding. Longitudinal seams shall be inspected after completion. The weld root area shall be examined during welding to verify proper penetration and fusion. The circumferentiall fillet welds should be magnetic particle or liquid entia penetrant examined after welding. Where delayed weld cracking is a concern, concern, nondestructive examination of the circumferential fillet weld should be performed not less than 24 hr after welding has been completed. Alternatively,, a welding procedure tively procedure qualified under high cooling cool ing rate, higher carbon equivalent (CE), and testing completed after 48 hr of welding per API 1104, Appendix B, 20th Edition, should be considered.
4.4 Welds Welds
sleeve’s longitudinal seams shall be butt welded to full penetration, as shown in Fig. 2. Provision for venting
4.5 Reduced Reduced Pressure Pressure Reducing the carrier piping or pipeline operating pressure, pressur e, and maintaining maintaining flow, flow, while the repair is b being eing made is recommended. See API RP 2201 for recommendations on welding pipe in service. The piping or pipeArticle lines 2.10may shall forvice in-to make the repair; alsobe also be consulted taken out of service ser repair; servicehowever, weldingburn-through issues. shall be considered. Recommended men ded press pressur uree durin during g sle sleeve eve install installatio ation n for piping piping or pipelines is between 50% to 80% of operating pressure.
5.4 In-Pr In-Proces ocesss Examinat Examination ion
4.6 In-Service Welding
The owner owner ma may y requi require re full “in “in-pr -proce ocess” ss” vis visual ual exa examimination, as described in para. 344.7 of ASME B31.3, of the sleeve weld installation. When “in-process” examination is performed, the results shall be documented. Examinations shall be performed by personnel meeting Nondestructive the qualification requirements specified by the applica ble code of construction or post-construction code.
All of the aspects for in-service welding of Type B sleeve circumferential and full penetration longitudinal seams are not addressed by this document. PCC, API, ASME, and other industry information pertaining to inservice welding shall be considered when planning inservice welding. At a minimum, qualification of the welding process shall take into account (a) the pote potenti ntial al for hyd hydrog rogenen-ind induce uced d cra cracki cking ng in the heat-affected zone as a result of accelerated cooling rate and of hydrogen in the weld environment
5.5 NDE Exa Examinat mination ion NDE examination methods shall be in accordance with ASME BPVC Section V and acceptance criteria in 29
Part 2 — Article 2.6
ASME PCC-2–2015
accordance with the applicable code of construction or post-construction code.
API 579-1/ASME FFS-1
AGA, American Gas Association, 6th Symposium on Line Research Defect Repair Procedures, J. F. Kiefner October Octob er 29, 1979 Publis Pub lish h er er : A m mee rica rican n Gas A ss ss ocia ociatt io ion n (A GA GA ), 400 North Capitol Street, NW, Washington, DC 20001 (www.aga.org)
Tightness 6 TE TEST STIN ING G A Leak Test should be performed on Type B sleeves in accordance with para. 6(a) or (b), as required by the
API RP 579, Fitness-for-Service API RP 2201, Safe Hot Tapping Practices in the Petroleum and Petrochemical Industries API Standard 1104, Welding of Pipelines and Related Facilities Publisher: Publishe r: American Petro Petroleum leum Institute (API), 12200 L S ttrr ee 122 ee t, t, NW, NW, Was ash h in ingt gton on,, DC 20 200005 (www.api.org) ASME B31.3, Process Process Piping ASME Boiler and Pressure Vessel Code, Section V — Nondestructive Examination ASME Boiler and Pressure Vessel Code, Section IX — Welding, Brazing, and Fusing Qualifications Publisher: The American Society of Mechanical Engineers (ASME), Two Park Avenue, New York, NY 10016-5990; Order Department: 22 Law Drive, P.O. Box 2900, Fairfield, NJ 07007-2900 (www.asme.org)
owner. (a) Perform a hydrotest of a Type B sleeve by pressurpressurizing the annulus between the sleeve and the carrier pipe, in accordance with the applicable construction or post-construction code. The test pressure shall be selected such that the inner pipe will not collapse due to external pressure. (b) Perform a Sensitive Sensitive Leak T Test est as described in para. 345.8 of ASME B31.3 or other recognized national standard.
7 REFE REFERE RENC NCES ES AGA, American Gas Association, Pipeline Repair Manual, December 31, 1994
Article 5.1 provides additional guidance.
30
ASME PCC-2–2015
Part 2 — Article 2.7
(2) Longitudinal Load. Unit forces in longitudinal direction:
(e) This repair method is generally used on the outside surface of components subject to internal pressure. For applications under external pressure, a separate analysis to evaluate buckling and other instability considerations shall be performed. (f) In In assess assessing ing the app applica licabil bility ity andservi andservice ce life of this this repair method, consideration shall be given to material compatibility, future operating conditions, thermal and shrinkage shrin kage effects effects of welding, welding, the intr introdu oduction ction of crevices crevices and stru structura cturall disco discontinu ntinuities, ities, ther thermal mal transient transientss and temperature differentials between the patch plate and the com compon ponen ent, t, and oth other er applic applicatio ation n limits limits suc such h as examination and testing constraints. If the damage to be patched is, or is expected to be, through-wall, the effects of fluids (e.g., entrapment, concentration, corrosion, etc.) that may accumulate between the vessel and the patch plate shall be assessed. If this repair method is to be imp implem lemen ented ted durin during g com compon ponen entt operati operation, on, add addiitional precautions may need to be taken for personnel safety. (g) The design may consider the combined strength of the patch plate and the underlying shell, taking into
F LP
F CP F CP
F LP
FLP
p
PDm
(2)
account the strength of the fillet weld and plug joints, including joint efficiency. efficiency . Consideration mayweld also be given to excess thickness available adjacent to the damaged shell using applicable code area replacement rules for nozzles. No credit shall be taken for material required for future corrosion allowance.
where FLP
3.2 Internal Pressure Loads Loads
(b) If other other loa loads ds are are applic applicabl ablee (such (such as bendin bending, g, torsion, wind, etc.), they shall be determined and added to the pressure load such that
4 p
(a) For cylindrical components subject to internal pressure loads, applied forces on the repair patch shall be determined as follows: (1) Circumferential Load. Unit forces in hoop direction: F CP
P
FC
F CP
FL
t
where Dm
p
FCP P
p
p
p
PDm 2
p
FCP + F CO
and
where FC
FCP
longitudinal force due to internal pressure, N/mm (lb/in.)
(1)
p
FCO
p
FL
p
FLO
p
p
FLP
p
FLO
total circumferential force from all loads, N/mm (lb/in.) circumferential force due to other applicable loads,, N/mm (lb/in.) loads total longitudinal force from all loads, N/mm (lb/in.) longitudinal force due to other applicable loads,, N/mm (lb/in.) loads
(c (c)) Appropriate alternative force calculations for spherical, torispherical, or ellipsoidal pressure components shall be used when applicable.
diameter at mid-wall of component, mm (in.)
3.3 Structural Di Discontinuity scontinuity Evaluation Evaluation (a) For stresses near a nozzle or other structural discontinuity contin uity to be insig insignifica nificant, nt, the minim minimum um distance distance
circumferential force due to internal pressure, N/mm (lb/in.) internal design pressure, kPa (psi) 33
MPa
Part 2 — Article 2.12
ASME PCC-2–2015
(2) Longitudinal Load. Unit forces in longitudinal direction:
analysis to evaluate buckling and other instability considerations shall be performed. (f) In In assess assessing ing the app applica licabil bility ity andservi andservice ce life of this this repair method, consideration shall be given to material compatibility, future operating conditions, thermal and shrinkage shrin kage effects effects of welding, welding, the intr introdu oduction ction of crevices crevices and structura structurall disco discontinu ntinuities, ities, ther thermal mal transient transientss and
F LP
temperature differentials thenpatch the com compon ponen ent, t, and oth other erbetween applic applicatio ation limits limitsplate suc such hand as examination and testing constraints. If the damage to be patched is, or is expected to be, through-wall, the effects of fluids (e.g., entrapment, concentration, corrosion, etc.) that may accumulate between the vessel and the patch plate shall be assessed. If this repair method is to be implem implemen ented ted durin during g com compon ponen entt operat operation ion,, addiadditional precautions may need to be taken for personnel safety. (g) The design may consider the combined strength of the patch plate (considering also the strength of the fillet weld joints, including joint efficiency) and the underlying shell. Consideration may also be given to excess thickness available adjacent to the damaged shell
F CP F CP
F LP
FLP
using applicable applicable code arearep area replacem lacement ent rule ruless for nozzle nozzles. s. No credit shall be taken for material required for future corrosion allowance.
where FLP
p
3.2 Internal Pressure Loads Loads
P
FC
p
p
FCP P
p
p
FCP + F CO
and
t
where Dm
(2)
F CP
where FC
p
longitudinal force due to internal pressure, N/mm (lb/in.)
FL
FCP
PDm 4
(b) If other other loa loads ds are are app applic licabl ablee (such (such as bendin bending, g, torsion, wind, etc.), they shall be determined and added to the pressure load such that
(a) For cylindrical components subject to internal pressure loads, applied forces on the repair patch shall be determined as follows: (1) Circumferential Load. Unit forces in hoop direction: F CP
p
PDm 2
(1)
p
FCO
p
FL
p
FLO
p
p
FLP
p
FLO
total circumferential force from all loads, N/mm (lb/in.) circumferential force due to other applicable loads,, N/mm (lb/in.) loads total longitudinal force from all loads, N/mm (lb/in.) longitudinal force due to other applicable loads,, N/mm (lb/in.) loads
(c (c)) Appropriate alternative force calculations for spherical, torispherical, or ellipsoidal pressure components shall be used when applicable. diameter at mid-wall of component, mm (in.) (15) 3.3 Structural Dis Discontinuity continuity Evaluation Evaluation (a) For stresses near a nozzle or other structural discontinuity contin uity to be insig insignifica nificant, nt, the minim minimum um distance distance
circumferential force due to internal pressure, N/mm (lb/in.) internal design pressure, kPa (psi)
MPa
66
ASME PCC-2–2015
exceed the nominal thickness of the repair plate or the original nominal component thickness. (c) In addition, load path eccentricity of the hoop stress in the shell plate and patch plate shall be considered. The perimeter welds bearing circumferential loads shall be sized such that
between the fillet welded patch plate and the existing discontinuity should be Lmin
where Lmin Rm
p
p
t
p
p
2(R 2(Rmt)1/2
(3)
plate setback distance (see Fig. 1), mm (in.) radius at mid-wall of component, mm (in.) wall thickness of component, mm (in.)
T /2
Equation (3) applies the setback distance (R ( Rmt)1/2 to both the existing nozzle (or other similar structural discontinuity) conti nuity) and the patch plate. This proximity limit also applies to the distance between adjacent fillet welded patch plates, in those applications where more than one is employed on a given component. (b) In those applications where the patch plate is to attach to existing nozzle reinforcement pads, the patch plate may be contoured to match the reinforcement pad perimeter and welded thereto with a full penetration joint. (c) In those applications where the damaged shell is Lmin of a nozzle or other structural discontinuity, within L within the patch plate should be designed as a reinforcement pad extending 360 deg around the nozzle/opening, and welded thereto with a full penetration joint. Alternatively, additional detailed analysis may be performed to evaluate local stresses. (15)
Part 2 — Article 2.12
T e t
t /2 Optional bevel
Sw
p
(PDm/2 /2T T ) + (3PD (3PDm e/T 2)
(5)
where e load path eccentricity (T (T + + t t)/2, )/2, mm (in.) Sw Sa calculated weld stress, MPa (psi); S (psi); S w ≤ 1.5 1.5S T wall thickness of patch plate, mm (in.) p
p
p
3.5 Col Cold d Forming Lim Limits its (a) Carbon and low alloy steel patch plates fabricated by cold forming shall not exceed 5% extreme fiber elongation. gati on. Theextr Theextrem emee fiber fiber elonga elongation tion shall shall be det determ ermine ined d as follows follows:: (1) (1) For For double curvature
3.4 Allowable Loa Load d on Perimeter Fillet Weld Weld (a) The perimeter weld shall be sized such that the allowable load on the weld exceeds the the longitudinal and circumferential loads in accordance with eq. (4).
R 75T 75T 1 − f Ro R f
w min
≤ 5%
(6)
where R f final centerline radius of patch plate, mm (in.) Ro original centerline centerline radius of patch plate (equals p
p
=
T F A ≥ w minESa
where E F A
p
Sa
p
wmin
p
p
(4)
infinity for flat plate), mm (in.) thickness of the patch plate, mm (in.)
(2) (2) For For single curvature
R 50T 50T 1 − f Ro R f
weld joint efficiency factor (0.55) allowable force on fillet welds, N/mm (lb/in.); F (lb/in.); F A > F C and F L allowable base metal stress, MPa (psi)1 minimum weld leg dimension, mm (in.)
≤ 5%
(7)
(b) Patches cold formed beyond these limits may be used provided they receive receive appropriate postforming stress relief prior to installation.
NOTE: The maximum design fillet weld size shall not exceed the thickness of the thinner material being joined nor 40 mm (1.5 in.).
(b) Alternatively, the perimeter weld edge preparation may be beveled to increase the weld’s effective throat thickness. In no case shall the effective throat 1
p
4 FA FABRI BRICA CATIO TION N (a (a)) Plate edges may be cut to shape and size by mechanical means such as machining, shearing, grinding, or by thermal means such as flame or arc cutting.
Compatible weld metal shall be of equal or greater strength.
67
(15)
Article 2.16 Welded Hot Taps in Pressure Equipment or Pipelines (insert new Article record# 10‐2044 )
See attached PDF file: 10-2044.pdf
Article 3.13 Crimping of Metallic Pipe (insert new Article record# 06‐1005)
See attached PDF file: 06-1005.pdf
ASME PCC-2–2015
Part 4 — Article 4.1
REVISED See attached PDF file: 10-2046 and 15-2094.pdf
PART 4 NONMETALLIC AND BONDED REPAIRS Article 4.1 Nonmetallic Composite Repair Systems: High-Risk Applicationss Application (15)
1 DESCRI DESCRIPT PTION ION
(2) the repair of tanks originally designed in accordance with a variety of construction standards, including AWWA D100, AWWA D103, API 620, API 650, BS EN 13121-2, and PD 5500 (3 (3)) the repair of vessels originally designed in accordance with a variety of construction standards, incl includ udin ing g ASME ASME BP BPV V Co Code de,, BS EN 1312 131211-2, 2, and and PD 5500 5500 (b) The Repair System qualification, design, installation, and operational requirements provided in this Article covers situations involving damage commonly encountered in fluid systems. (c) The following type of defects can be repaired (and are assessed in para. 3.3.3): (1) external corrosion where structural integrity is compromised. In this case it is probable the application of a Repair Repair System will arrest arrest further deterioration. deterioration. (2) external damage such as dents, dents, gouges, fretting, fretting, or wear (at supports).
1.1 Scope Scope (a) This Article provides the requirements for the repair of fluid system components (e.g., pipework, pipe pipe-lines, tanks, and vessels) using a qualified Repair System. (b) The Repair System is defined as a combination of the following elements for which qualification testing has been completed: (1) substrate (component) (2) surface preparation (3) composite material (repair laminate) (4) load transfer material (filler material) (5) (5 ) primer layer adhesive (an adhesive used in some repair systems, attaching the composite laminate to the substrate) (6) application method (including sealing, coating, etc., as needed) (7) curing protocol (8) interlaminar adhesive for Repair Systems that utilize precurved plies (c) The composite materials allowed for the Repair System include, but are not limited to, glass, aramid, or carbon fiber reinforcement in a thermoset polymer (e.g., polyester, polyurethane, phenolic, vinyl ester, or epoxy) matrix. Fibers shall be continuous.
(3) cracks can be repaired in accordance with this Article if they are prepared in accordance with excavation requirements of Article 3.4. (4) either internal corrosion or erosion (leaking or nonleaking). In this case, it is probable that corrosion will continue and the assessment needs to take this into account. (5) leaks. (6) manufacturing or fabrication defects. (d) Internal fluids and external environments affect the compatibility of the composite. The pressure/ temperatur temper aturee limits are depe dependen ndentt on tthe he type of damag damagee being repaired and the Repair System being used. These limits are determined by the testing and qualification requirements of this Article. A lower temperature limit of −50°C (−58°F) can be assumed unless a lower temperature capability is demonstrated through qualification testing.
1.2 Applicabi Applicability lity (a) This Article is applicable to a wide variety of components as follows: (1) the repair of pipework and pipelines originally designed in accordance with a variety of construction standards, including ASME B31.1/B31.3/B31.4/B31.8, and ISO 15649 and ISO 13623 143
ASME PCC-2–2015
Part 4 — Article 4.1
Table able 2 Service Service Temper Temperatur ature e Limits for Repair Repair Systems Property Measurement T g
Substrate Leaking,
HDT
T m
T g − 30°C (54°F)
HDT − 25°C (45°F)
tmin
Substrate Not Leaking, T m
p
D Es · · (P − P s) 2s Ec
(c) For axial stresses stresses due to inter internal nal pre pressur ssure, e, bend bending, ing, and axial axial thrust thrust,, the min minimu imum m repai repairr lam lamina inate te thickn thickness ess,, tmin, is given by
T g − 20°C (36°F)
HDT − 15°C (27°F)
tmin
p
D
·
2s
6
10−5 (T m − T d)2 + 0.001 (T (T m − T d) + 0.70 0.7014 14
c
p
2
10−5 (T m − T d)2 + 0.006 (T (T m − T d) + 0.70 0.7014 14
D2
(4)
p
ts PliveD PD − s − 2Ec trepair Ec trepair 2(E 2(Ectrepair + E sts)
(5)
(c) If the repair is applied at zero internal pressure, i.e., P live 0, then eq. (5) can be rearranged to give i.e., P p
trepair
p
1 cEc
PD − st s 2
(6)
(d) The assumptions made in deriving eqs. (5) and (6) are that the substrate material is elastic, perfectly plastic pla stic,, i.e i.e., ., no strainhard strainhardeni ening ng andthat no def defectasses ectassesssmentt is performed men performed other than use of the minimum remaining wall thickness (of the substrate) to infer the internal pressure at the point of substrate yield. (e) The value of the allowable strain of the composite in the circumferential direction can be taken from eqs. (10a) (10a) and (10b) (10b) or if perfor performan mance ce data data are are availa available ble,, fr from om Mandatory Appendix V. The appropriate service factor is taken from Table 4. (f) Fo Forr ax axia iall lo load adss in pi pipe pelin lines es,, eq. eq. (7 (7)) shal shalll be uti utiliz lized ed..
(1 (1))
(Temperatures in Fahrenheit) f TT
− P s
Ec
that the underlying substrate does yield and the repair laminate is designed based on the allowable strain of the composite. Only hoop loading should be considered in determining the design repair laminate thickness. (b) For hoop hoop strain strain du duee to inter internal nal press pressur ure, e, thedesig thedesign n repair laminate thickness, trepair, may be calculated by iteration using
(Temperatures in Celsius) p
2F 2 F
·
3.4.3.2 Under Underlying lying Substrate Substrate Yields (a) In the derivation of eqs. (5) and (6) it is assumed
3.4.2 Service TTemperature emperature Effects Effects (a) The Repair System shall not be used above the values of T T m listed in Table 2. (b) In absence of other Repair System qualification data [see para. II-3(b) of Mandatory Appendix II], the allowable strains to be used in eqs. (8) and (9), and the service factors to be used in eqs. (10a), (10b), (13), (14), and (15) shall be down-rated by the temperature factor, f TT , given in eqs. (1) and (2).
f TT
Es
(d) The design repair laminate thickness, t repair, shall be the greater value determined from eqs. (3) and (4). (e (e)) Where the purpose of the Repair System is to strengthen an undamaged section of the component to carry additional bending or other axial loads, the value of F shall be taken to be the increased total axial load requirement and the value of Ps shall be the original MAWP/MAOP/MOP. The value of F depends on the specific application details and shall be considered by the Repair System designer (outside the scope of this Article).
(2) Type B Desi Design gn Case. Case. Componen Components ts leaki leaking ng requirrequiring structural reinforcement reinforcement and sealing of through-wall defects. (a) The The des design ign method method in par para. a. 3.4 3.4.6 .6 shall shall be use used d in addition to the Type A design case. (b) For components with active internal corrosion, the repair laminate shall be designed on the assumption assum ption that a thr through-w ough-wall all defect will occur if the remaining wall thickness at the end of service life is expected to be less than 1 mm (0.04 in.). (c ) The greater thickness of the Type A and Type B design case shall be taken as the repair laminate thickness, trepair. The Type B design case is often the thickness, limiting case. (b) Paragraphs 3.4.9 and 3.4.10 shall shall be considered for each design case and applied where appropriate, with the largest thickness being taken as the repair laminate t repair. thickness, t thickness,
0.0006
(3)
(2 (2))
The maximum allowable value of f f T T is 1.
3.4.3 Component Component Allowable Allowable Stress. Use of the the design des ign method method in this this sec section tion is app appro ropri priate ate if the con contri tri- bution of the component is to be included in the calculation for load-carrying capability.
trepair
3.4.3.1 Under Underlying lying Substrate Substrate Does Not Yield (a) In the derivation derivation of eqs. (3) and (4), it is assum assumed ed that the underlying underlying substrate substrate does not yield. (b) For hoop str stresse essess due to internal internal pre pressur ssure, e, the minimum repair laminate thickness, t thickness, t min, is given by
p
1
aEa
PD − st s 4
(7)
where ts may be conserva conservatively tively the minim minimum um wall thickthickness or the equivalent remaining wall thickness based on the defect assessment. 149
ASME PCC-2–2015
(h) The value of E E ac and 2 in eqs. (13) to (15) shall be E c)0.5 and (v taken as (E (Ea · · E (vca2 · E a/Ec), respectively, as the repair laminate is anisotropic, i.e., the properties of the material are different in the axial and circumferential directions.
area is determined to be less than 1 mm (0.04 in.) at the end of its life. (c) For For a circula circularr or nearnear-cir circul cular ar defect defect,, the min minimu imum m repair laminate thickness, t thickness, tmin, is iterated using eq. (13).
P
p
f TT f
LLCL CL
2
3.4.7 Impact (a) For repairs to leaking components, components, the Repair
(13)
System supplier shall demonstrate demonstrate that the Repair System is capable of withstanding a low velocity 5 J (44.3 in.-lb) impact in accordance with the procedure described in Mandatory Appendix VI. (b) The repai repairr lamina laminate te thickn thickness ess,, as de desig signed ned per this this Article, may be insufficient to address external impact loads. Consideration should be given to increasing the laminate repair thickness or providing other methods of protection.
(1 − ) 3 d4 + 1 d + 3 d2 E Gtmin 64 64Gt 512 512tt3min
(1) Equation (13) is valid for defect sizes where d ≤ 6Dt, Dt, where E where E ac EaEc. (2) The value of f is f is set to 0.333 (or Table 4 if performance data is available). (d) For noncircular defects that have an aspect ratio less than 5, eq. (13) shall be used where the value of dd is selected such that it contains the defect. (e) Where the Repair System incorporates a plug to allow the repair of a live component, the qualification tests carried out to determine the value of (Mandatory (Mandatory Appendix IV) shall be conducted on the whole Repair p
3.4.8 Axia Axiall Length of Repai Repair r (a) Unless Unless it can b bee demonstrate demonstrated d that that a sho shorter rter rep repair air length is sufficient, the design thickness of the repair laminate shall extend beyond the damaged region in (17 the component, L component, L over, by Lover
System including any plug arrangement. (f ) For a circumferential slot defect, the minimum thickness for a repair laminate, t laminate, tmin, is iterated using the smallest value of the repair thickness calculated from both eqs. (13) and (14). Note that t that t min can be iterated in eq. (14).
P
p
Part 4 — Article 4.1
p
2.5 Dt Dt/ /2
(16)
(b ) F For or repair repairss des designe igned d in accord accordance ance with para. 3.4.6, L 3.4.6, L over shall be the greater of (18) Lover
p
max. 2.5 D Dt/2 t/2 or
Ea a trepair
(17)
(c) The total axial length of the repair is given by
f TT f
LLCL CL
(1 − 2) 1 3 W 4 + W + 3 Eac 16 16G G31tmin 4 24t 24tmin
L
4 + 5 2 W 2 (1 + )
(18)
(d) The ends of the the rep repair air shall be taper tapered ed if the the rep repair air thickness is governed by axial loads (paras. 3.4.4, 3.4.5, and 3.4.6). A minimum taper of approximate approximately ly 5:1 should be used.
(14) f TT f D 8Etmin
2Lover + L defect + 2Ltaper
p
(19)
(15)
(e) The to overlap length shallload. also be designed to be sufficient transfer the axial
(g) For an axial slot-type defect, where the circumferentiall width of the slot, entia slot, W W D/2 mm (in.), the minimum thickness for a repair laminate, T m min in mm (in.) is calculated using
3.4.9 Component Fittings (a) Equations (3) through (12) relate to the stresses in the substrate (component) under combinations of internal pressure pressure and axial load. For fittings, such as bends, bends, reducers, tees, flanges, and nozzles, the stress systems are more complex and may need further consideration. Calcul Cal culatio ations ns ma may y be bas based ed on press pressur uree stress stress mul multipl tiplier ierss for components taken from ISO 14692 or ISO 24817. (b) The pressure stress stress multiplier for bends, reducers, reducers, and other components where the membrane stress due to pressure is the same as for simple component shall be taken as unity unity,, and for pipe tees shall be taken as 2. The diameter required for repair design is the largest
P
p
p
P
p
f TT f
LLCL CL
E D4 + 2 (1 − 2 ) D 4 G 4 D 4 + + + 6 Eac 3 3 8 384 384ttmin 11,520ttmin 11,520
(16)
where the limit on the applicability of eq. (16) is given by < 1, where is the angle subtended by the axial slot (radians).
diameter of the component. 3.4.10 Other Design Con Considerat siderations. ions. Paragraphs 3.4.10.1 through 3.4.10.6 may be applied if appropriate. 151
Part 4 — Article 4.1
ASME PCC-2–2015
3.4.10.1 External External Loads Loads (a) To resist external pressure or vacuum applied to the Repair System, the minimum repair thickness, t thickness, t min, is given by
2
tmin
p
3 (1 − )Pe D 2Ec
(h) These equations are intended for cyclic internal pressure loading only, but may be applied with caution to axial axial loads, loads, prov provide ided d they they remai remain n ten tensil sile, e, i.e., i.e., the equations are not applicable for reversible loading.
(20)
1/3
(19)
3.4.10.3 Fire Performanc Performance e (a) The requiremen requirements ts for fire performance performance shall be identified in the risk assessment.
(1) Flame spread and smoke generation shall also be considered in the assessmen assessment. t. (2) Due account shall be taken of the response of the Repair System (component substrate and the repair laminate). In many cases additional fire protection will (21)not be necessary, as the damaged original component tmin 3 2Ec can stil stilll be abl ablee to perfor perform m sat satisf isfact actori orily ly du durin ring g the sho short rt Pext, soil < (20) 3 (1 − 2) D duration of a fire event. (b) Strategies for achieving fire performance may where include the following: 2 2 (1) application application of additional additional wraps of repair repair lami D 1 D D 4 h + + soil − D h + Pext, soil soil nate mat materi erial al suc such h tha thatt eno enough ugh bas basic ic compos composite ite will 2 3 8 2 D remain intact for the duration of the fire event (2) application of intumescent external coatings where 2 is defined as (v (vca2 · E a/Ec). (3) application of intumescent and other energy (c) For repairs to buried components, see Article 4.3,
(b) For soil loads, to preven preventt the collapse of a buried repaired component, the external soil pressure Pext, soil shall be less than the collapse resistance of the Repair System, P System, P c
p
absorbent materials within the repair laminate (4) use of polymer formulations with specific fireretardant properties. (c) Further Further det details ails of fire fire perfor performan mance ce and fire fire miti mitigagation methods are contained in ASTM E84 or ISO 14692.
Mandatory Appendix I for additional technical requirements. 3.4.10.2 Cyclic Cyclic Loading Loading (a) Cyclical loading shall be considered in the risk assessment for the application of the Repair System. (b) Cycli Cyclicc loa loadin ding g is not necess necessari arily ly lim limite ited d to inter internal nal pressure loads. Thermal and other cyclic loads should also be considered when assessing cyclic severity. (c) If the predicted number of pressure or other loading cycles is less than 7,000 over the design life, then cyclic loading does not require consideration. (d) If the predicted number of pressure or other loading cycles exceeds 7,000 over the design life, then cyclic loading shall be considered using eqs. (21) and (22). The
3.4.10.4 Electrical Conductivity (a) For repairs to metallic substrates, it is likely that the properties of the substrate will satisfy electrical conductivity requirements. requirements. (b) Where the substrate is insulating, e.g., glass FRP, and electrical conductivity requirements are specified, the electrical conductivity properties of the Repair System should be measured to ensure that the original characteristics of the substrate are restored. (c) Electrical Elect rical conductivity conducti vity14692. testing details are contained in ASTM D149 or ISO
equations are conservative for lower numbers of cycles. (e) If the predicted number of pressure or other loading cycles exceeds 10 8 over the design life, then in eqs. (21) and (22), N (22), N shall shall be set to 108. (f) For the design of nonleaking defects, paras. 3.4.4 and 3.4.5, the composite allowable strain strain in both circumcircumferential and axial directions, c and a, eqs. (10a) and (10b), shall be derated by the factor, f c , where where f c is given by
3.4.10.5 Environmental Compatibility (a) The suitability for use of the Repair System in the service serv ice env environ ironmen mentt shall be based on the following considerations. (1) The service service environ environmen mentt is the env environ ironmen mentt that will contact the repair laminate. It may be either the (22) external or internal environment. (2) When required by the service environment, the 1 (1 − R 2c ) (21) R2c + f c Repair Rep air System System sha shall ll be protec protected ted fro from m UV exposu exposure re 2.888Log (N (N ) − 7.108 (e.g., sunlight), water, and damaging chemicals, either as an inherent characteristic of the Repair System or by (g) For the design of leaking pipes (para. 3.4.6), the the application of coating or mechanical barrier. service factor, factor, f , in eqs. (13) through (15) shall be replaced by (b) The qualification qualification of the Repair System System (para. 3.2) (23) shall ensure that the Repair System is compatible with 1 aqueouss and hydrocarb aqueou hydrocarbon on environ environmen ments ts at the qualif qualificaicaR2c + f 0.333 (1 − R 2c ) (22) 2.888Log (N (N ) − 7.108 tion temperature. In general, thermoset polymers are p
p
152
ASME PCC-2–2015
Part 4 — Article 4.1
3.5 Appro Approval val
compatible with a wide range of environments but consideration needs to be given when the environment is strongly acidic (pH < 3.5), strongly alkaline (pH > 11), or is a strong solvent, e.g., methanol, toluene in concentration greater than 25%. (c) When the compatibility of the Repair System is unknow unk nown, n, the then n the Rep Repair air System System sup supplie plierr sha shall ll prov provide ide
Designs of repairs according to this Article shall be authorized by a Professional Engineer (or international equivalent) or shall be undertaken by a technically competent person acceptable to the owner.
3.6 Requa Requalific lification ation
one of the following to demonstrate demon strate compatibility: ility: (a (a)a ) Where there has been a change to the Repair (b) The System Manufacturer shall have quality (1) (1Repair )in environmental compatibility data from the program place, such as ISO compatib 9001, that demonstrates System, then the testing specified in the relevant paras. polymer supplier, demonstrating that the environment consistent and repeatable production quality. 3.6.1 and 3.6.2 shall be completed if required by is no more more aggressiv aggressivee than aqueous or hydrocarb hydrocarbon on Nonmandatory (c) The qualityat program pr shall include batch testing of theAppendix B. environments theogram design temperature. (b) If the modified Repair System is found to be of qualified(2)Repair Systemdata Materials. The frequency of sampling if no compatibility from the polymer suplower low er per perfor forman mance ce than than the ori origin ginal al system system,, then then it sha shall ll plier tests is av availabl ailable, e, then specific spec ific environ env mental tal testing and the required shall beironmen specified by the Repair System be treated as a new system and validated according to is required. Results from tests according to one of the requirements of this Article. Supplier. Batch testing may include tests suchthe as: following followi ng test procedure procedures, s, ASTM D543, ASTM C581, (c) per If theunit modified Repair System is found to be of Physical of the fabric (e.g. area) ASTM D3681, properties ISO 10952 or equivalent, comparing the mass higher performance than the original system, then it Tensile properties of theand fibers exposure of the specific environment aqueous envimay be treated as a new system and validated accordin according g ronme ronment nt to the repai repairr lamina laminate te the des design ign temper temperatu ature re Tensile properties ofat the laminate to the requirements of this Article or the data from the shall be performed. The Repair System shallof be the considoriginal Repair System may be used. Glass transition temperature polymer ered compatible to the specific environment if the test Gel from times of theenvironment polymerare no worse than 3.6.1 For Ty Type pe A Repairs results the specific Compression strength of filler material (a) Testing shall be performed as specified in sections for the aqueous environment. II-2 through II-4 ofRepair Mandatory Appendix II. (d) When erosion is the cause of the degradation pro(d) Test results shall be retained or be retrievable by the (b (b)) Where the Repair System has been validated cess of the substrate material and the repairby laminate is number. System Supplier and be traceable batch according to section II-6 of Mandatory Appendix II, the in contact with the eroding medium, then the repair (e) The Re Repair pair System Supplier shall label Repair System system shall be subject to the survival testing specified laminate may suffer material loss. The Repair System Materials issued with the relevant batch number(s). in para. V-2.1 of Mandatory Appendix V. supplier shall demonstrate that despite this potential • • • • • •
loss of laminate material, the Repair System should survive for the specified repair lifetime.
3.6.2 For Ty Type pe B Repairs (a) Testing shall be performed as specified in sections II-2, II-3, and II-5 of Mandatory Appendix II. (b) A minimum of thre threee tests are required, required, and rresults esults shall be compared with LCL of the original Repair System.
3.4.10.6 Cathodic Cathodic Disbondment Disbondment (a) For repairs to components that are cathodically protected, it may be required to demonstrate that the repair will not disbond due to the cathodic protection system. (b) ASTM G8, ASTM G42, or ASTM G95 shall be used to demonstrate that the repair will not be susceptible to substantial disbondment under an imposed electrical current.
3.4.11 Desig 3.4.11 Design n Output (a) The out output putss of the des design ign cal calcul culatio ations ns of therepai therepairr laminate are the following: (1) number of layers, n layers, n (2) total axial repair length, L [from eq. (18)] (b) The number of layers for installation purposes is
4 FABRICA FABRICATION TION (INSTALLA (INSTALLATION) TION) 4.1 Genera Generall The repair thickness to be installed shall be expressed as the number of layers to be applied (based on the minimum minim um thickness thickness per lay layer er determined determined dur during ing validavalidation); see para. 3.4.11.
Materials 4.2 Repair Mat Material erialssSystem of Con Constructi struction on (a) The materials of construction shall be those for which the qualification qualification and design has been completed. completed.
(24) n
p
trepair tlayer
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4.3 Stora Storage ge Conditions Conditions (a) Storage of material shall comply with the Repair System supplier’s instructions. (b) The MSDS shall be retained for reference. (c) The materials used shall be stored and controlled according to national safety regulations (e.g., OSHA or COSHH).
where n shall where n shall be not less than 2 and rounded up to the nearest whole number. (c) The layer thickness, t thickness, tlayer, may be determined from the thickness of the Tension Test Coupons divided by the number of layers used in preparing the coupons. 153
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ASME PCC-2–2015
Part 4 — Article 4.1, Nonmandatory Appendix A
Article 4.1, Nonmandatory Appendix A Glossary of Terms and Acronyms A-1 GLOSSARY GLOSSARY OF TERMS
load transfer material: material used to repair external surfac sur facee imp imperf erfecti ectionsprior onsprior to theapplicatio theapplication n of compos compos-ite laminate.
anisotropic: exhibiting differen differentt prop properties erties in differen differentt directions.
modified qualified Repair System: a System: a Repair System, develA quantity of a material that is batch: Barcol hardness: measure hardness: measure of surface hardness using a surop oped ed by modi modify fyin ing g on onee or moreelem moreelemen ents ts of a pr prev eviou iousl sly y face impresser. impresser. produced in a single qualifi qua lified ed Repair Repairproduction System System,, for which whirun ch theor qua qualifi lificati cation on testtest-
ingof rec recomme ommended nded by Nonma Nonmandat ndatory ory Appendix Appendix B of single manufacture. A batch composite: a ther thermosetplastic mosetplastic (polymer) (polymer) that is reinfor rei nforced cedcycle this Article has been completed. compl eted. by fibers. may be divided into one or more lots. owner: the owner: the company or entity that owns or is responsible continuous (fiber): unbroken (fiber): unbroken fiber lengths throughout the for the substrate being repaired. structure. pipeli pip eline: ne: pipe with components (e.g., bends, flanges, cure or curing: setting curing: setting of a thermosetting polymer by an valves) subject to the same design conditions and irreversible chemical reaction. typically typica lly used to trans transport port fluidsbetween plants, plants, usually usually delamination: separation separation of layers layers within a composite composite buried. laminate or between the laminate and the host pipe. pipework: interconnected pipework: interconnected piping subject to the same set design life: expected life: expected maximum service service period of the or sets of design conditions. repair under the design conditions. piping: assemblies piping: assemblies of piping components (e.g., pipe, fittings, flanges, gaskets, bolting, valves) used to convey fluids within a plant, often above above ground b but ut sometimes buried.
design life data: data: information necessary to support a “design life” for a repair. This information could include long-term strength, long-term modulus, cyclic fatigue, chemical exposure, temperature, and impact and abrasion resistance.
ply: a ply: a single wrap or layer (lamina) of a repair laminate. postcure: additional postcure: additional elevated temperature cure.
differential scanning calorimetry (DSC): method of differential determining the glass transition temperature of a thermosetting polymer.
qualified Repair System: System: a Repair System for which the qualification qualifi cation testing mandated by this Article has been completed.
disbondment: separation of the laminate from the substrate.
reinforcement: a high str reinforcement: a strengt ength h fiber imbed imbedded ded in the plastic (polymer), resulting in mechanical properties supe-
glass transition temperature: temperature temperature: temperature at which a polymer undergoes a marked change in physical properties.
rior to those of the base polymer. resin system: all of the components that make up the matrix mat rix (pl (plast astic ic or polyme polymer) r) portion portion of a compos composite. ite. Ofte Often n this is a resin, filler(s), pigment, mechanical property modifiers, and catalyst or hardener.
hardener: component added to an polymer resin to affect hardener: component cure (curing agent). heat distortion temperature: temperature temperature: temperature at which a standard test bar deflects a specified amount under a given load.
risk: a term encompassing what can happen (scenario), risk: a its likelihood (probability), and its level of damage (consequences).
laminate: the part of a Repair System that is the composlaminate: the ite. Most composites considered in this document are composed of discrete lamina or layers, which are wrappe wra pped d or stacked stacked,, one on top of theother. theother. This This stac stacked ked construction is the “laminate.”
Shore hardness: measure hardness: measure of surface hardness using a surface impresser or durometer. substrate: the substrate: the original component to be modified. supplier: the company or entity taking responsibility for supplier: the testing testing and qua qualify lifying ing a Re Repai pairr Sys System tem;; usuall usually y themanufacturer, but possibly a provider of private-relabeled
leak: this does not refer to a fluid leaking through a hole leak: this or breach in the pipe. Rather, this refers to a condition of a pipe (substrate) wall that could or does allow the contents of a pipe to make contact with and act directly upon the (composite) repair laminate.
product. thermoset polymer: plastics polymer: plastics that cannot be resoftened following polymerization. 175
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Part 4 — Article 4.2
Article 4.2 Nonmetallic Composite Repair Systems: Low-Risk Applicationss Application (15)
1 DESCRI DESCRIPT PTION ION
(c) (d) 1.1.1 Repa Repair ir Requireme Requirements. nts. This Article Article prov provides ides (e) the requirements for the repair of low-risk components (f) (e.g., pipework, pipelines, tanks, and vessels) using a 1.1 Scope Scope
qualified Repair System.
1.1.2 Definition of of Repair System. System. The Repair System is defined as a combination of the following elements for which qualification testing has been 0.16 completed: (a) substrate (component) (b) composite surface preparation (c) material (repair laminate) (d) load transfer material (filler material) (e) primer layer adhesive (an adhesive used in some repair systems, attaching the composite laminate to the substrate) (f) (f ) application method (including sealing, coating, etc., as needed) not be randomly (g) curing protocol (h) interlaminar adhesive fororiented Repair Systems Systems that utilize precurved plies
Materials. terials. The composite composite materials materials Structural 1.1.3 Allowed Ma
(c) non-IDLH fluids (d) less than 150 psig (1 MN/m 2) (e) less than 120°F (50°C) s (f) above 0°F (−20°C) (g) the leaking defect size, d size, d,, and design pressure, P pressure, P,, satisfy the following relationship: (1) P d < 150 psig (in.)0.5 (2) p d < 0.5 MN/m1.5 (3) the defect size shall be limited to d ≤ 0.25 D
1.2.3 Appli Applicabl cable e Defects. Defects. The following following types types of defect may be repaired: (a) external (b) external corrosion damage (c) internal corrosion and/or erosion (d) leaks (e) manufacturing or fabrication defects
(b)
1.3 Risk A Assess ssessment ment
(a) A determination shall be made as to whether the repair is low risk, as defined in para. 1.2. The risk assessment should define the acceptable life of the repair. An assessment of the risks associated with the defect and repair method should - be completed.
allowe allowed d for theRepair theRepair System System ar aree engine engineeri ering ng fiber fiber (e.g., (e.g., carbon, carbo n, glass, glass, aramid) aramid) rein reinforc forcemen ements ts in a ther thermose mosett polymer matrix (e.g., polyester, polyurethane, phenolic,
(d) The information and data describing any hazards
vinyl ester, or epoxy). Fibers shall be continuous (i.e., chopped fibers shall not be used).
shall be included in the risk assessment to be used on site.
1.2 Applicabi Applicability lity
NOTE: See Article 4.1 4.1 for gu guidanc idancee in risk asse assessmen ssment. t.
1.4 Repai Repairr Life Life
1.2.1 Example Applications. This Article addresses the repair of components originally designed in accordance with a variety of standards, including API 620, API 650, ASME BPV Code, ASME B31.1, ASME B31.3, AWWA WWA C200, AWWA WWA C300, AWWA WWA C301 C301,, AWW WWA A C302 C302,, AWWA WWA C303 C303,, AWW WWA A C400, C400,A AWW WWA A C402, C402,A AWW WWA A D100, AWWA D103, BS EN 13121-2, ISO 15649, ISO 13623, and PD 5500. 1.2.2 Definition of Low Risk. Low-risk applications, for the purposes of this Article, are defined as those applications where all of the following apply: (a) nonhazardous fluids (b) systems systems containing containing piping, tanks, and pressure pressure vessels not critical to the safety of workers
(c)
NOTE:
The specified repair life shall be defined by the risk assessment, and the achievable repair life will depend on the Repair System. The useful service period of the Repair System for a specific application can be affected by external and environmental environmental exposures, active internal corrosion/erosion, and external mechanical influences. This Article is applicable as follows:
2 LIMIT LIMITAT ATION IONS S
(a) the repair of pipework and pipelines originally designed in accordance with a
2.1 Additi Additional onal Requiremen Requ irements ts variety of construction standards, including ASME B31.1, B31.3, B31.4, B31.8 and Part ISO 15649 an 13623. 1 of this Standard
contains additional requireandoflimitations. This Article shall be used con- of (b)ments the repair tanks originally designed in accordance within a variety junction with Part 1. construction standards, including AWWA D100, AWWA D103, API 620 and API 650.
or non-IDLH
181(c)
the repair of pressure vessels designed in accordance with a variety of
construction standards, include ASME BPV Code and EN 13445 Standard.
Part 4 — Article 4.2
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ASME PCC-2–2015
2.2 Qualifica Qualification tion of Repair Syste System m
T g
(a) The use of this Article shall be limited to those Repair Systems for which the qualification testing describ des cribed ed in Mandato Mandatory ry Appe Appendix ndix II has been been completed (see para. 3.2 for qualification data). (b) Any change to any element element of the Repair System (see para. 1.1 for scope) shall constitute constitute a diff differe erent nt and
(a) The installation procedures shall be those used in the Repair System qualification. If the installation procedures are not those used in the Repair System qualification, then the repair repair is not in compliance with this Article.
(b)
If other loads are present within the repair area, in addition to internal pressure, then Article 4.1 shall be used.
3 DE DESI SIGN GN (15)
(15)
(a) Qualification of the Repair System shall be completed in accordance with Table 1 and Mandatory Appendix II. (b) Materials performance and test data shall be measured by a certified nationally accredited test facility, (d) The RepairorSystem supplier shall state the type of defects (asEngineer or certif certified ied by a register registered ed Professi Professional onal Engineer (or international equivalent). listed in Part 1, Table 1, Guide for (c) The Repair System supplier shall specify the folthe Selection of Repair Technique) lowing parameters: to (1) which their Repair System has component material been qualified. (2) surface preparation (3) (3 ) repair laminate (polymer matrix and fiber reinforcement) (4) reinforcement orientation (5) overlaps between neighboring wraps (6) overlaps between individual layers (7) filler material (dimensional restoration), if used (8) adhesive/primer, if used (9) application instructions (d) Any change in the above parameters to the Repair Repair System Sys tem sha shall ll constit constitute ute a new new Re Repai pairr Sys System tem and requir requiree qualification.
2.3 Install Installation ation
2.4 Loading Loading
glass transition temperature determined per Table 1, °C (°F)
3.2 Repai Repairr System Qual Qualifica ification tion Data
therefore new Repair System. (c) This new new Repair System System shall require require qualif qualification ication as described in Mandatory Appendix II. See also para. 3.2.
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p
3.1 Symbols Symbols
3.3 Additi Additional onal Required Required Data These are the symbols used throughout this Article. (a) The following data should be provided for each D component outside diameter, mm (in.) repair: d diameter (or diameter of the equivalent cir(1) lifetime requirements/expectation of the repair cle) of the defect defect or leaking region, region, mm (in.) service life d f design factor (2) (2 ) required determined per Table 1 design and operating pressures/ Ec tensile modulus for the composite laminate temperatures in the circumferential direction determined (3) expected future service conditions per Table 1, N/m2 (psi) (4) piping line identity HDT heat distortion temperature, °C (°F) (5) description of the component, including mateL total axial repair length, mm (in.) rial specification and wall thickness axial length of the LLdefect (6) streng strength th per ply per thickn thicknessthat essthat may may be cal calcucu overlap length, mmdefect, (in.) mm (in.) over lated by the following relationship: L taper length, mm (in.) p
p
p
p
p
p
p
p
taper
p
n
p
n A
p
nB
p
n H
p
P Swa Swh t T d
p
p
p
p
p
number of layers layers as determined by the relevant repair design case minimum number of layers for Type Type A repairs (axial direction) minimum number of layers for Type B repairs minimum number of layers for Type Type A repairs (hoop direction) repair design pressure, N/m2 (psi) wrap axial tensile strength per ply per meter (per inch) determined per Table 1 wrap hoop tensile strength per ply per meter (per inch) determined per Table 1 wall thickness of substrate, mm (in.) design temperature of Repair System, °C (°F)
Swa and S wh (psi per ply per in.) and S load at failure of coupon, lb / cross-sectional area of coupon thickness of coupon / number of layers of coupon p
(b) The data used in the design shall be recorded. Mandatory Appendix I may be utilized. Mandatory utilized.
3.4 Cal Calcula culations tions (a) The design of the repair laminate shall be carried out using the requirements in the following sections. There are two design cases: (1) Type A Design Case. For components that are not leaking leaking (requirin (requiring g structura structurall rein reinforc forcemen ementt only) only).. This shall be calculated for all repairs. (2) Type B Design Case. This Case. This shall be calculated for components that are leaking. 182
ASME PCC-2–2015
Part 4 — Article 4.2
Table 1 Repair System System Required Required Material Material and Performance Performance Properties Properties Property
Test Type
Tensile strength ( S Swa a, S wh w wh ) and tensile modulus ( E E c c ) [Note (1)]
Mandatory
Detailed Properties
Tensile strength ( s ), modulus ( E E ), Poisson’s ratio (for leaking pipes and some design cases; strain to failure in both
Minimum Values
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Strain to failure must > 1%
ISO 527, ASTM D3039
hoop and axial directions) Glass transition temperature ( TT g )
Mandatory or use HDT below
Glass transition temperature ( T T g )
None, except that this can determine the maximum operating temperature of the Repair System
ISO 11357-2, ASTM E831, ASTM E1640, ASTM E6604
Heat distortion temperature (HDT) [Note (2)]
Mandatory or use T g above
Heat distortion temperature (HDT)
None, except that this can determine the maximum operating temperature of the Repair System
ISO 75, ASTM D648
3
Long-term lap shear performance
Optional
Measurement of lap shear strength after 1 000-h heat exposure
30% of lap shear adhesion strength
Mandatory Appendix II-2
Adhesion strength
Mandatory
Lap shear Leak sealing performance (optional)
Mandatory Appendix III
ASTM D3165, BS EN 1465
NOTES: (1) S wa wa and S wh wh are calculated from the coupons used in the test methods (tensile strength times thickness of the ply). (2) For the matrix polymer polymer (without the reinforc reinforcing ing fibers), use ASTM D648 or ISO 75 to meas measure ure HDT under a load of 1.82 MPa (264 psi). As an alternative, when measuring HDT for reinforced polymers, the minimum load should be 18 MPa (2,640 psi).
(b) A component shall be considered to be leaking if the wall thickness at any point of the affected area is expected to be less than 1 mm (0.04 in.) at the end of
(c) The design repair minimum required number of layers shall be the greater of the values determined. (d) For tees, the number of layers shall be twice the
the repai repairr lif life. e. Thi Thiss should should take acc accoun ountt of active active intern internal al corrosion where applicable. (c) For nozzles, elbows, bends, reducers, and flanges, the repair thickness calculated in paras. 3.4.1 and 3.4.2 shall be used.
number determined in para. 3.4.1(c). For pipe tee joints, the diameter of the larger pipe shall be used in the calculation.
3.4.2 Type Type B Design Case (a) The number of wraps, nB, applied shall be that qualified in Mandatory Appendix III. (b) For tees that are leaking, the number of layers shall be the greater number of that determined in para. 3.4.1 and n and n B.
3.4.1 Ty 3.4.1 Type pe A Design Case (a) For hoop stre stresses sses due to inter internal nal pressur pressure, e, the minimum number of wraps, n wraps, n H , is given by n H
p
PD 2d f Swh
(1)
3.4.3 Axia Axiall Length of Repair (a) The design thickness of the repair laminate shall extend beyond the damaged region in the component L over . by by L
where d f is set at 0.2 and S wh is taken from Table 1. where d (b) For any cases where the substrate wall thickness has been reduced by 50% or more, then the following
Lover
calculation calcul ation shall be made made:: n A
p
PD 4d f Swa
(2)
p
2.5 Dt Dt/ /2
(b) Lover shall be at least 0.05 m (2 in.). 183
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Part 4 — Article 4.2
ASME PCC-2–2015
should be used Tabl able e 2 Hold Points Points During During Install Installation ation
(c) Th Thee endsof endsof th thee re repa pairmay irmay betapere betapered. d. A mini minimu mum m taper len taper length gth,, L taper, o f a p pp p rro ox xii ma ma te t e ly ly 5 :1 :1 i s recommended. (d) The total axial length of the repair is given by L
p
2Lover + L defect + 2Ltaper
Hold Point
Materials preparation ) reinforcement ) polymer
(4)
Substrate surface preparation ) inspection
(e) The repair shall be centered over the defect.
3.4.4 Environmenta Environmental l Compatibility. Compatibility. The suitability Filler profile 4.2 Materials of Construction of the Repair System for use in the service environment Stage check reinforcement lay-up and design (a) speci Thefied materials of construction shall be those for which theonqualification specified by the owner shall be determine determined. d. Inspection of repair laminate has been completed. 3.4.5 3.4. 5 Desig Design n Output ) cure (hardness) (b) The Repair System Manufacturer shall have a quality program in place, such as ) number of wraps (thickness) (a) The out output putss of the des design ign cal calcul culatio ations ns of the repai repairr ) dimensions and position ISO laminate 9001, that consistent and repeatable production quality. are thedemonstrates following: ) external inspection (see Table 3) the number of layers, n layers, n, , shall include be determined by testing of fibers and fabrics, polymers (c) The(1)quality program shall batch test the appropria appr opriate te desig design n case speci specified fied in par para. a. 3.4 ( (n n shall (resins and curing agents) and fillers. The frequency ofPressure sampling and the tests required not be less than 2) shall be(2)specified by the Repair System Supplier. Batch testing may include tests such total axial repair length, L as: (b) The Rep 4.3 Installa Installation tion Guidance Guidance Repair air System System install installer er sha shall ll be pr prov ovide ided d wit with h thePhysical following information: properties of the fabric (e.g. mass per unit area) (a) Repair System suppliers shall provide installation (1) details of laminate lay-up, including number instructions. These instructions shall include (where Tensile properties of the fibers of layers, repair area to be covered, and orientation of appropriate) Tensile properties of the composite individual layers of reinforcement (this may be pre• • •
environmental conditions of site at sented as a transition written description or a drawing incorporatGlass temperature of the polymer time(1) of acceptable repair ingGel standard details such polymer as overlap and taper) times of the • (2) material storage (2) d details etails of surfa surface ce pre preparatio paration n procedu proc edure, re, includinclud (3) surface preparation Compression strength of filler material • ing method of application, equipment to be used, and (4) by polymer (d) inspection Test results or be retrievable the mixing Repair System Supplier and methodshall be retained or (5) laminate lay-up be traceable byofbatch number. (3) details in-fill required to achieve a smooth (6) laminate consolidation outer Repair profile prior to the Supplier application shall of the repair (e) The System label Repair Materials issued with the (7)System cure laminate relevant batch number(s). (8) key hold points (4) details of cure protocol (b) Further details of these requiremen requirements ts can be found in Mandatory Appendix V. 3.5 Approval Approval (c) The key hold points that may be observed during Designs of repairs according to this Article shall be a repair are summarized in Table 2. undertaken by a technically competent person accept(d) The results from the inspection of the repair lamiable to the owner. nate shall meet the acceptance criteria of the design •
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3.6 Requalific Requalification ation Where there has been a change to the Repair System, then the relevant testing specified in Article 4.1 shall be completed.
output. 4.4 Live R Repair epairss 4.5 (a) Repairs Repairs to nonleaking nonleaking,, live componen componentt syste systems ms are possible, provided that the associated hazards are fully consi consider dered ed in tthe he risk assessme assessment nt for the opera operation. tion. This should include any hazards to and from surroundi rou nding ng equipm equipmen entt in add additio ition n to the com compon ponen entt being being repaired. (b) The tensile (radial) stresses induced induced into the adhesive bond as a result of the thermal contraction differences between the composite and component substrate upon the removal of live loads may be ignored.
4 FABRI FABRICA CATION TION (INSTALLA (INSTALLATION) TION)
NOTE: 4.1 Storage Storage Conditions Conditions (a) Storag Storagee of materia materiall shouldcomplywith shouldcomplywith thesupplithesupplier’s instructions. (b) The MSDS should be retained for reference. (c) It should be noted that the materials used will need to be stored and controlled according to national safety regulations (e.g., OSHA or COSHH). 4.3 4.2 Installer Installer Qualifications Qualifications
5 EXAMIN EXAMINAT ATION ION
Personnel involved in the installation of a Repair System shall be trained and qualified for that Repair System according to Mandatory Appendix IV.
5.1 Intro Introduction duction (a ) This section provides guidance on the postinstallation/operational issues of Repair Systems. The 184
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Part 4 — Article 4.2
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ASME PCC-2–2015
6 SYS SYSTEM TEM PRESSURE PRESSURE TESTING TESTING
ASTM E831-2012, 2014 Standard Test Method for Linear T he he rm rm aall E xp xp aan n si si o on n of So oll iid d M aatt er er iiaa llss b y Thermomechanical Analysis 2013 ASTM E1640-20 E1640-2009, 09, Stan Standar dard d Test Method Method for Assignment of the Glass Transition Temperature by Dynamic Mechanical Analysis Publisher: American Society for Testing and Materials
(a) System System press pressur uree testing testing,, if requi require red, d, sha shall ll be spe specicified by the owner. (1) A service test at the operating pressure should be performed. (2) See Article 5.1 for guidance on pressure testing. (3) Any Any si sign gnss of le leak akag agee or indi indica catio tion n of re repa pair ir lamlaminate failure shall be cause for rejection of the repair. (b) All repairs shall be cured in accordance with the Repair System supplier instructions before pressure testing. (c) If the test pressure exceeds the pressure for which the Repair System has been designed, then the repair shall be redesigned for this higher pressure. (15)
(ASTM 100 Barr Harbor Drive, P.O. BoxInternational), C700, West Conshohocken, PA 19428-2959 (www.astm.org) AWWA C200-12, Standard for Steel Water Pipe 6 in. (150 mm) and Larger AWW AW WA C300-11, Reinforced Concrete Pressure Pressure Pipe, Steel-Cylinder Type AWWA WWA C301-0 C301-07, 7, Prestre Prestressed ssed Concrete Concrete Pre Pressur ssuree Pipe, 14 Steel-Cylinder Type AWW AW WA C302-11, Reinforced Concrete Pressure Pressure Pipe, Noncylinder Type AWWA AWW A C303-08, Concrete Pressure Pressure Pipe, Bar-Wrapped, Bar-Wrapped, (W) Steel Cylinder Type AWWA C400-03, Asbestos-Cement Pressure Pipe 4 in.– 16 in. (100 mm–400 mm) for Water Distribution
7 REFE REFERE RENC NCES ES 7.1 Reference Referenced d Codes Codes and Standards Standards
-1is a list of publications The following referenced in 2007 this Article.
(W)
API 579/ASME FFS-1, Fitness-For-Service API 620-2008, Construction of Large, 2013 Design and Construction Welded, Low-Pressure Storage Tanks 2012 Welded Steel Tanks for Oil Storage API 650-2007, Publisher: Publishe r: American American Petroleum Petroleum Institute (API), 12 1220 20 L S tr tr ee ee t, t, NW, NW, Was ash h in in gt gt on on,, DC 20 20005 005 (www.api.org)
Systems AWWA C402-05, Asbestos-Cement Transmission Pipe, 18 in. Through 42 in. (450 mm Through 1 050 mm) for Water Supply Service AWWA D100-11, Welded Steel Tanks for Water Storage AWWA D103-09, Factory Coated Bolted Steel Tanks for Water Storage Publisher: Publis her: Amer American ican Water Works Association Association (A (AWW WWA), A), 6666 West Quincy Avenue, Denver, CO 80235 (www.awwa.org)
ASME Boiler and Pressure Vessel Code 2014 Power Piping ASME B31.1-2010, 2014 Process Piping ASME B31.3-2010, ASME PCC-2-2015 Repair of Pressure Publisher: The American Society E uiofmMechanical ent and Pi inBS EN 59:1977, Measurement of hardness by means of Engineers (ASME), Two Park Avenue, New York, a Barcol impressor NY 1001610016-599 5990; 0; Or Order der Depart Departmen ment: t: 22 Law Drive, Drive, P.O. BS EN 146 1465:2 5:2009 009,, Determi Determinati nation on of tensil tensilee lap she shear ar Box 2900, Fairfield, NJ 07007-2900 (www.asme.org) strength of rigid to rigid bonded assemblies BS EN 13445:2012 Unfired BS EN 1312113121-2:2 2:2003 003,, GRP tanks tanks and ve vesse ssels ls for use above above ASTM D648-2007, Test Method forLoad Deflection Pressure Vessels Temperature of Standard Plastics Under Flexural in the Edgewise Position ASTM D1599-1999 (2011), Test Method for Short Time Hydraulic Hydr aulic Failur Failuree Pressure Pressure of Plastic Pipe, T Tubing ubing and Fittings ASTM D2240-2005 (2010), Standard Test Method for Rubber Property — Durometer Hardness 2013 Standard Test Method for IndentaASTM D2583-2007, tion Hardness of Rigid Plastics by Means of a Barcol Impressor 2014 Standard ASTM D3039-2008, Test Method for Tensile (R2014) Properties of Polymer Matrix Composite Materials ASTM D3165-2007, Standard Test Method for Strength Properties of Adhesives in Shear by Tension Loading of Single-Lap-Joint Laminated Assemblies ASTM D6604-2000 (R2013) (2009), Standard Practice for glass transition temperatures of Hydrocarbon Resins by Differential Scanning Calorimetry
ground — Part 2: Composite materials — chemical resistance BS EN 13121-3:2008(2010), GRP tanks and vessels for use abo above ve gr groun ound d — Part 3: Desig Design n and workma workmansh nship ip PD 5500:2012, Unfired fusion welded pressure vessels Publisher: British Standards Institution, Inc. (BSI), 12110 121 10 S un un se se t Hills Hills R oad oad,, R es es ton ton , VA 201 201990 (www.bsigroup.com) ISO 75:2006, -1:2013Plastics — Determination of temperature of deflection under load -- Part 1 General test method 2012 Plastics — Determination of tensile ISO 527-1:2002, properties — Part 1: General principles ISO 527-2:2012, Plastics — Determination of tensile properties — Part 2: Test conditions for moulding and extrusion plastics ISO 868:2003, Plastics and ebonite — Determination of indentation hardness by means of a durometer (Shore hardness) 186
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2013 Plastics — Differential scanning caloISO 11357-2:1999, rimetry rime try (D (DSC) SC) — Part 2: Determina Determination tion of glass glass trans transiition temperature ISO 13623:2009, Petroleum and natural gas industries — Pipeline transportation systems ISO 15649:2001, Petroleum and natural gas industries — Piping
ASTM D5379, D5379, Stan Standar dard d Test Method Method for She Shear ar Properties of Composite Materials by the V-Notched Beam Method Publisher: American Society for Testing and Materials (ASTM International), International), 100 Barr Harbor Drive Drive,, P.O. Box C700, West Conshohocken, PA 19428-2959 (www.astm.org)
Pu ub b llii sh sh eerr : In ntt eerr n naa ti t i on on aall O rrg g an an iz iz aatt io io n f or or Standardization (ISO), Central Secretariat, 1, ch. de la Voie-Creuse, Case postale 56, CH-1211 Gene` ve 20, Switzerland/Suisse (www.iso.org) (www.iso.org)
BSity 7910, Guideinon methods for assessing the acceptabilof flaws metallic structures Publisher: British Standards Institution, Inc. (BSI), 12110 Sunset Hills Road, Reston, VA 20190 (www.bsigroup.com)
7.2 Related Related Codes Codes and Standard Standardss
ISO 8501, Preparation of steel substrates before application of paints and related products ISO 8502, Tests for the assessment of steel cleanliness ISO 8503, Surface roughness characteristics of blast cleaned steel substrates ISO 8504, Surface preparation methods ISO 10952, Plastics piping systems — Glass-reinforced thermosetting plastics (GRP) pipes and fittings — Determination of the resistance to chemical attack from the inside of a section in a deflected condition
The followi following ng are rela related ted codes codes and standa standards. rds. Unless Unless otherwise specified, the latest edition available may be used. ASME B31G, Manual for Determining Remaining Strength of Corroded Pipelines: Supplement to B31 Code for Pressure Piping Publisher: The American Society of Mechanical Engineers (ASME), Two Park Avenue, New York, NY 10016-5990; Order Department: 22 Law Drive, P. O O.. Bo Bo x 2 90 90 0, 0, F ai ai rrff ie ie ld ld , N J 0 70 70 07 07 -2 -2 90 900 (www.asme.org)
ISO 11359-2, Plastics — Thermomechanical (TMA) — Part 2: Determination of coefficientAnalysis of linear thermal expansion and glass transition temperature P ub ub llii ssh h eerr : In ntt er er na na ti ti o on n aall O rrg g an an iz iz aatt io io n fo orr Standardization (ISO), Central Secretariat, 1, ch. de la Voie-Creuse, Case postale 56, CH-1211 Gene` ve 20, Switzerland/Suisse (www.iso.org) (www.iso.org)
ASTM D3681, Standard Test Test Method for Chemical Chemical Resistance of Fiberglass (Glass-Fiber-Reinforced Thermosetting Resin) Pipe in a Deflected Condition
ASTM D1599 Test method for short time hydraulic failure pressure of plastic pipe, tubing and fittings
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Part 4 — Article 4.2, Mandato Mandatory ry Appendix I
Repair Data Sheet Job Reference
Component Details Component identification Material / grade External diameter Wall thickness Component contents Operating temperature
Minimum
Pressure
Operating
Maximum Design
Test
Comments
Repair Requirements (see para. 1.2 of Article 4.2) Repair type
e.g., A or B
Repair design pressure, P
(non-leaking)
(leaking)
Repair Specification Nature of defect Defect length, l Defect size used in design, d
Diameter
Depth
Cause of defect
Corrosion
Erosion
Location
External
Internal
Leaking
Y or N
Position on component (e.g., 6 o’clock)
Conditions During Implementation of Repair Component temperature Ambient temperature Humidity External environment Constraints Details of Repair Applied Number of layers Length of repair
Repair Materials Manufacturer Batch number Installed date Installed time Installer Name
Prepared by:
Date:
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Article 4.2, Mandatory Appendix II Qualification Data for Repair System strength shall be
shall be performed (15)
determined by (HDT) or at temperature. (d) heat distortion temperature theroom glass transition temperature (T (T g) for the Repair System shall be gre at er than th an 60 60°C °C (1 (140 40°F °F), ), det ermi er mined ned by a te st according to Table 1 of Article 4.2
II-1 II-1 INTROD INTRODUCT UCTION ION (a) This Mandatory Mandatory Appendix Appendix descr describes ibes the qualifi qualificacation data that the Repair System supplier shall provide to be in compliance with this Article. (b) It is a requirement that all qualification tests are carried out using the same substrate material, surface preparation, repair laminate, filler material, adhesive, and application method (see para. 1.1 of Article 4.2). Any substantive change to the Repair System shall constitute a new Repair System and require require qualification. qualification. (c) Qualification testing shall be completed in accordance with the latest edition of the test standard (see para. 7.1). 7.1). Updates to the test standa standards rds shall shall not require require qualification qualifi cation testing to be repeated repeated..
(d)
II-3 DATA DATA FOR COMPO COMPOSITE/S SITE/SUBSTR UBSTRAT ATEE INTERFACE (a) The lap shear test shall be carried out according to Table 1. (1) This short-term test shall be used to determine the average shear strength or the locus of failure. (2 (1)) Minimum average lap shear strength of 4 MN/m2 (580 psi), or failure of the substrate, shall be demonstrated for all substrates. (3) (b) Alternatively Alternatively,, it shall be demonstra demonstrated ted that the adhesive bond is stronger than the shear strength of the repair laminate or substrate by assessing the surface of the substrate material used in a lap shear specimen after testing. (2) Cohesive
and curing protocol (15)
II-2 DATA DATA FOR REPAIR REPAIR LAMINATE LAMINATE
s in Table 1.
The following data/properties are required: shall be (or strength (a) tensile strength per layer per meter per layer per inch) in tension for hoop direction (S (for Swh) demonstrated and axial direction (S (Swa) metal substrates (b) minimum tensile modulus (E (Ec) of 7 109 N/m2 (1,000,000 psi) (c) Barcol hardness or Shore hardness determined by test according to Table 1 of Article 4.2 (if applicable)
metal
II-4 ADDITIONAL ADDITIONAL REQUIREMEN REQUIREMENTS TS FOR FOR LEAKING SUBSTRATES The following data are required: Demonstration of leak sealing capacity, determined by test according to Mandatory Appendix III.
load transfer material (if needed), primer layer (if needed), interlaminar adhesive (if needed),
shall be determined:
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Article 4.2, Mandatory Appendix III Validation V alidation for Repair of Leak Leaking ing Component III-1 III-1 INTROD INTRODUCT UCTION ION
laminated with the holes in the 6 o’clock orientation. Three tests shall be completed at ambient temperature. (b) The repair thickness applied shall be calculated using eq. (2) of Article 4.2 for a pressure of 1 MN/m 2 (150 psig). At least two layers of reinforcing material shall be used for the test. The tested repair thickness shall be defined as n as n B. (c) Internal pressure shall be applied and the repair shall not fail below 3 MN/m2 (450 psig). Pressurization rate shall be in accordance with ASTM D1599.
This Mandatory Appendix describes the testing required require d to val validate idate the Repai Repairr System for repair repair of leaks of various components. (a) The Rep Repair air System System sha shall ll be va valid lidated ated after the successful completion of three tests on one pipe size. (b) Only one pipe size needs to be qualified.
II IIII-2 2 METH METHOD OD (a) Sections of pipe of minimum diameter 100 mm (4 in.) and minimum thickness of 3 mm (0.12 in.) shall be used. A circular hole of 25 mm (1 in.) i n.) diameter shall
IIIIII-3 3 REPO REPORT RT A report shall be prepared giving the test conditions, details of thepressure Repair System, points (final of test). and the individual data
be through the wall thickness of the should substrate anddrilled the repair laminate applied. All samples be
(d) Pressurization rate shall be such that the maximum test pressure is reached in a minimum of 30 seconds (longer pressurization time is preferred). (e) Qualification requires the repaired pipe to survive loading to 3 MN/m2 (450 psig) internal pressure and show no visual signs of degradation when inspected in accordance with Table 3 of Article 4.2. (f) No visible leakage is the acceptance criteria.
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Article 4.2, Mandatory Appendix IV Installer Qualification IV-1 IV-1 INTROD INTRODUCT UCTION ION
(2)
(1)
(b) A written test covering the above subjects shall be taken and passed by the installer.
(a) The repair of components using composite laminates differs considerably from other repair techniques and the quality quality of the installation installation depends depends strongly strongly on satisfactory craftsmanship. Training and qualification of personnel are therefore key elements of a successful repair rep air.. This Mandatory Mandatory Appendix Appendix outlin outlines es the minim minimum um requirements for training, qualification, and approval of installers and supervisors. / trainers. trainers. (b) Training should be arranged by or with the assistance of the Repair System supplier or other qualified training expert.
IV-2.2 IV-2. 2 Coursework Supervisor Supervisor (Supervisor / Trainer) (a) The supervisor shall be a qualified installer. (b) The supervisor shall complete the following additional training: / trainer (1) supervisor’s duties and responsibilities (2) evaluation methods used in repair design / trainer's trainer's (3) health and safety (4) installation checklist and hold points (5) inspection of repairs (c) A written test covering the above subjects shall be taken and passed by the supervisor.
IV-2 IV-2 TRAINI TRAINING NG
IV-2.3 Installer-Specific Installer-Specific Qualification
(a) Courses and training shall be arranged by or with the assistance of the Repair System supplier. (b) Training raining shall give a theoretic theoretical al and practical practical intr introoduction to the most important elements in the installation of the Repair System.
(a) Install Installer erss sha shall ll be qua qualifi lified ed for each each spe specif cific ic Repair Repair System through practical tests.for T e A and/or T (b) All specific approval tests shall be carried out in accordance with relevant installation procedures. (c) Repair shall pass visual inspection completed in accordance with para. 5.2 of Article 4.2 witnessed by a supervisor or instructor.
IV-2.1 Installer Coursework (Installer) (a) Training shall include the following: (1) definition of a Repair System (2) terminology, types of repair (3) hazards associated with pressurized systems (4) health, safety, and environment (5) surface preparation
IV-3 IV-3 REC RECORD ORD OF TRAINING TRAINING RECORDS The employer of the Repair System installers shall keep records of their training.
(6) (7) material material preparation application (8) control of repair conditions (9) quality control
IV-4 IV-4 QUAL QUALIFICA IFICATION TION PERIOD PERIOD Th Thee qual qualif ifica icatio tion n shal shalll rema remain in val alid id fo forr a peri period od of 1 yr following the installation of the last successful repair.
training in:
The course
Supervisors and trainers shall have the same qualification requirements, but may be different positions with the organization of the Repair System vendor.
192
and supervisors / trainers
e B.
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Part 4 — Article 4.2, Mandato Mandatory ry Appendix V
Article 4.2, Mandatory Appendix V Installation V-1 INTRODUCTION
V-4 CURE
(a) Repair Repair System System sup suppli pliers ers sha shall ll prov provide ide ful fulll install installaation instructions. (b) The requirements given in the following sections are intended to complement those given by Repair System suppliers and specify the key operations necessary for a successful repair. (c) In the the event of conflict, the Repair S System ystem supplie supplierr should shoul d be contacted contacted for clarif clarification ication..
(a) Since the cure of a repair repair lamina laminate te may be stro strongly ngly influenced by temperature and the correct mixing of polymer constituents prior to lamination, the limits set by Repair System supplier shall not be exceeded without approval from the Repair System supplier. (b) The time for full cure is dependent on the type of polymer used in the repair and ambient conditions. (c) If the component pressure has been reduced prior to repair, then the repaired component shall not be returned to its normal operating pressure until satisfactory cure has been achieved.
V-2 SURFACE PREPARATION (a) The surface preparation shall extend at least over
the whole surface onto which the repair laminate is to be applied and be in accordance with the specific Repair V-5 DOCUMENTATION DOCUMENTATION (15) System. (b) Assessment of the prepared surface for roughness (a) A record for each repair should be made and retained andcleanlin andclean lines esss shouldbe shouldbe prov provide ided d by theRepair theRepair Sys System tem for the repair life. supplier suppl ier.. The specified specified surfa surface ce pre preparati paration on techn technique ique (b) A unique identifier should be assigned to each repair. shall not be replaced by another, without explicit guid- (c)The records that should be kept include the following: ance from the Repair System supplier, who shall have (1) (a) Design Records Records qualified the alternative as part of a different Repair (i) (1) layers and orientation of reinforcement System. (ii) (2) preparation procedure (c) Any chemicals used for surface preparation shall iii) cure protocol (3) be within the recommended recommended shelf life, freshly mixed (iv) (4) postcure (where appropriate). (v) (5) number of layers (d) The time period between surface preparation and (vi) (6) axial extent of repair initial coating/laminate coating/laminate application application should be as short (vii) (7 ) design design data (Mandato (Mandatory ry Appendi Appendix x I of as possible (e.g., to avoid formation of flash corrosion). Article 4.2) and calculations (e) Pre Prepare pared d surfaces surfaces shall be pro protected tected from contaminatio contamination n (viii) (8) location of repair pri prior or to the app applica lication tion of the repai repairr lamina laminate. te. Det Deteri eriora ora-(2) tion of of th thee prepare prepared d surface surface should be cause for rejection rejection (b) Material Material Records (i) and the surface preparation procedure repeated. (1) Repair System supplier ii) (2) polymer type and quantity (iii) (3) reinforcement type and quantity (15) V-3 LAMINATE LAY-UP (iv) (4) batch numbers for materials The specific Repair System may need to include (c) Quality Control Records (3) instructions for (i) repair reference number (1) (a) in-fill compounds (ii)) visual inspection report (see Table 3 of (2 (b) primer application Article 4.2) (c) polymer/adhesive preparation (iii) thickness measurement (3) (d) reinforcement orientation (iv) repair dimensions (4) (e) overlaps between neighboring layers (v)) qualification for personnel completing (5 (5) completing the (f) overlaps between individual layers installation (g) consolidation of the layers (h) finishing layer/coating (top coat) (iv) (6 ) Barcol or Shore hardness measurement (if specified) (i) taper details (see para. 3.4.5 of Article 4.2)
load transfer material (if needed) / primer layer (if needed)
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Article 4.2, Nonmandatory Appendix A Glossary of Terms and Acronyms A-1 GLOSSARY GLOSSARY OF TERMS
piping: assemblies of piping components (e.g., pipe, fit piping: assemblies tings, flanges, gaskets, bolting, valves) used to convey fluids within a plant, often above ground but sometimes buried.
Barcol hardness: measure hardness: measure of surface hardness using a surface impressor impressor..
composite: a ther thermosetplastic mosetplastic (polymer) (polym er) thatAis quantity rein reinforc forced ed of a material that is batch: ply: a single wrap or layer (lamina) of a repair laminate. ply: a by fibers. produced in a single production or polymer system: all system: all ofrun the components that make up the cure or curing: curing: setting of a thermosetting polymer, e.g., single cycle of manufacture. A batch matrix mat rix (pl (plast astic ic or polyme pol ymer) r) portion por tion of a compos composite. ite. Ofte Often n polyester, epoxy, by an irreversible chemical reaction. thisone is a resin, filler(s), pigment, mechanical property may be divided into or more lots. delamination: separation separation of layers layers within a composite composite modifiers, and catalyst or hardener. laminate. reinforcement: a high high streng strength th fiber fiber imb imbedd edded ed in thepolydifferential different ial scanning calorimetry (DSC): method of mer,, resul mer resulting ting in mecha mechanic nical al prope propertie rtiess superi superior or to tho those se determining the glass transition temperature of a therof the base polymer. mosetting polymer. risk: a risk: a term encompassing what can happen (scenario), disbondment: separation of the laminate from the subdisbondment: its likelihood (probability), and its level of damage strate (pipe). (consequences). glass transition temperature: temperature temperature: temperature at which a polyShore hardness: measure hardness: measure of surface hardness using a surmer undergoes a marked change in physical properties. face impressor or durometer. hardener: component added to a resin to affect cure of hardener: component the thermoset polymer.
substrate: the original pipe or pipe component to be modified.
heat distortion temperature: temperature temperature: temperature at which a standard test bar deflects a specified amount under a given load.
supplier: the supplier: the company or entity taking responsibility for testing testing and qua qualify lifying ing a Repair Repair System System;; usuall usually y themanufacturer, but possibly a provider of private-relabeled product.
in-fill material: material: material material used to repair external surface imperfections prior to the application of composite wrap.
thermoset polymer: thermoset polymer: these these are plastics that cannot be resoftened following polymerization.
laminate: the part of a Repair System that is the composlaminate: the ite. Most composites considered in this document are composed of discrete laminaInstitute or layers, which are API: American Petroleum wrappe wra pped d or sta stacke cked, d, one on top of theother. theother. This This stac stacked ked
A-2 GLOSSARY GLOSSARY OF ACRONYMS ASME: The ASME: The American Society of Mechanical Engineers
construction is the “laminate.”
AWWA:leak: American Water Works Association leak: this this does not refer to a fluid leaking through a hole BPV: (ASME) Boiler Pressure Vessel or breach in the & pipe. Rather, this refers(Code) to a condition
ASTM: American ASTM: American Society for Testing and Materials BS (BSI): British (BSI): British Standards Institute
of a pipe (substrate) wall that could or does allow the contents of a pipe to make contact with and act directly upon the (composite) laminate. (BS) European Normrepair (or Norme
COSHH: Control Control of Substances Substances Hazardous Hazardous to Health Health Regulations
EN: owner: the owner: the company or entity that owns or is responsible Européenne)
DSC: Differential DSC: Differential Scanning Calorimetry
for the pipe substrate being repaired.
FRP: Fiber FRP: Fiber Reinforced Plastic/Polymer
pip eline: pipeli ne: pipe with components (e.g., bends, flanges, valves) subject to the same design conditions and typically used to transport fluids between plants, usually buried.
HDT: Heat HDT: Heat Distortion Temperature
pipework: interconnected piping subject to the same set pipework: interconnected or sets of design conditions.
MSDS: Materials Safety Data Sheets MSDS: Materials OSHA: Occupational OSHA: Occupational Safety and Health Act
IDLH: Immediately IDLH: Immediately dangerous to life or health ISO: International ISO: International Organization for Standardization
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4.4 4.3 Polymer Polymer Appli Applicatio cation n
Part 4 — Article 4.3
(c) All inspection/examination and corrective action shall be in accordanc accordancee with Mandatory Mandatory Appendix Appendix II.
(a) Polymer shall be applied in even and overlapping 4.3 Materials of Construction patterns until design thickness is achieved. Monit Monitoring oringof Plans Plans (a)beThe5.5 mater materials ials construction shall be those (b) When reinforcing fibers are added, they shall A plan for monitoringand the corrosion of abeen parfor to which (a) the qualification designrate has evenly dispersed, wetted, and rolled/compressed tially deteriora deteriorated ted host pipe shall be pre prepare pared. d. remove voids. Then the top layer of polymer is applied completed. (b) No monitoring plan is required for a fully deterioover the reinforcing fibers to provide a smooth, mono-
(b) The Repair Repair System Manufacturer shall have a lithic liner. rated host integrity pipe, since CIPP isas sized to provide program in place, ISO 9001,full that structural integrity. . the such (c) If pultruded or preimpregnated carbon isquality being (c) A plan for monitoring CIPP for degradation due demonstrates consistent and repeatable utilized, then the application process shall be as follows: to environm environmental ental conditions, erosion, or thermal (1) apply adhesive layer of polymer production quality. expansion/contraction should be prepared. (2) press the carbon into the adhesive polymer (c) The quality program shall include batch testing (3) apply the top coat to the structural liner to proof fibers and fabrics, polymers (resins and curing vide a smooth, smooth, monolithic monolithic surface 6 TE TEST STIN ING G agents) and fillers. The frequency of sampling and sy syste stem m pr pres essu sure re test test sh shal all l be pe perf rfor orme med d onthe the the CI CIPP PP the tests A required shall be specified by Repair 5 EXAMIN EXAMINAT ATION ION as specified in paras. 6.1 and 6.2. System Supplier. Batch testing may include tests 5.1 Test Sample Retrieval Isolable ble Pipe Pipe such as:6.1 Isola Samples may be taken in accordance with the following for each CIPP batch installed: Physical (e.g. mass 6.1.1 Pressu Pproperties ressure re Decay Tof est.the Thefabric system system integrity test (a) Samples Samples shall shall be take taken n on cou coupon pon specim specimens ens idenidenburied components that are isolable by valves or per unitfor area) tical to material applied onto the host pipe (similarly other means should consist pressure decay over time Tensile properties of of the fibers cured). that determines the leakage rate. composite (b) Number of samples shall be sufficiently large to Tensile properties of the 6.1.2 Fluid Volum Volume e Makeup Test. Test. Alternatively, Alternatively , the provide statistically adequate number of specimens for Glass transition temperature of the polymer system integrity test may consist of a fluid volume each of the test procedures required in material testing Gel times of the apolymer makeup to maintain set pressure over time that deter(para. 5.2). Compression strength of filler material mines the leakage rate. (c) Samples shall be marked to provide traceability. (d) Test results shall ebe retained retained or ptable be retrievable 6.1.3 Acceptanc Acceptance Criteria. The acceptable acce rate of 5.2 Material Te Testing sting by the Repair Supplier and be traceable by pressure System loss or volume makeup should be established The test samples obtained in accordance accordance with the over a minimum of 1 hr. Factors that may influence the batch number. para. 5.1 requirements for test sample retrieval should acceptable rate of pressure loss or volume makeup are (e) be tested to confirm the following design basis material mat erialThe Repair System Supplier shall label Repair (a) volume of the system pressure test property values: System Materials issued with the relevant batch (b ) leak tightness requirements for the buried (a) time-temperature-corrected flexural modulus of number(s). components •
• • • • •
elasticity for CIPP (E (EF from Mandatory Appendix I) (b (b)) time-temperature-corrected ultimate tensile strength of CIPP (S (ST from Mandatory Appendix I)
6.2 Nonis Nonisolab olable le Pipe
(c) the coefficient of thermal expansion used in the analysis required by Mandatory Appendix I
system integ integrity rity 6.2.1 6.2. 1 Flow Impairm Impairment ent Test. The system test for nonisolable buried components should consist of a test to confirm that flow during operation is not impaired.
5.3 CIPP-Installed CIPP-Installed Geometry Verification Verification (a) The minimum installed CIPP wall thickness shall be verified to meet the design requireme requirements nts using ultrasonic or other examinations. (b) Examin Examinatio ation n shall shall be in acc accor ordan dance ce with with app appro rove ved d procedures by qualified personnel. (c ) A set of four measurements, equally spaced around the circumference of the CIPP, should be taken at each end and at one intermediate point. (d) Additional sets of measurements should be taken in areas of significant host pipe degradation.
6.2.2 6.2 .2 Chan Change ge in Flow Flow Test. Alternatively, Alternatively, the system integr integrity ity test ma may y determ determine ine the cha change nge in flow flow betwe between en the ends of the buried components. components. 6.2.3 Acceptance C Criteria. riteria. The acceptabl acceptablee flow or change in flow should be established.
7 REFE REFERE RENC NCES ES 7.1 Referenced C Codes odes and Standards Standards
5.4 Documentation of CIPP As-Installed Condition (a) A visual examination shall be performed. (b) Voids, surface flaws, and areas of improper curing shall be evaluated.
API RP 579 (latest edition), Fitness-for-Service Publisher: Publishe r: American Petro Petroleum leum Institute (API), 12 1220 20 L S tr tr ee ee t, t, NW NW,, Was ash h ingt ington on,, DC 20 20005 005 (www.api.org) 199
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Article 4.3, Mandatory Appendix III Glossary of Terms and Acronyms III-1 GLOSSA GLOSSARY RY OF TERMS
surcharge: loading on a buried host pipe produced by surcharge: ground transportation traffic, e.g., truck or railway.
cured-in-place cured-in-pl ace pipe (CIPP): (CIPP): the bur buried ied pip piping ing modifi modificati cation on method with a thermoset polymer into a host pipe.
thermoset thermos et polymer: polymer: these these are plastics that cannot be resoftened following polymerization (includes Bakelite, curing: the curing: the changing of material properties of a thermoepoxy, epoxy vinyl esters, A, polyurethane, quantity of polyesters, a material that is and set polymeric system by the application of heat, water, batch: paints). radiation, or other means into a more stable and usable
produced in a single production run or single cycle of manufacture. A epoxies: these are usually a two-component thermoset III-2 may GL GLOSS OSSARY ARYdivided OF ACRONYMS ACROinto NYMSone or batch be polymeric system primarily composed of epichlorahy ASME: The ASME: The American Society of Mechanical Engineers lots. drin and Bisphenol A combined with an amine-based more condition.
curing agent.
(ASME).
fully deteriorated host pipe: pipe: a a host pipe that is not relied upon to support soil, surcharge, or groundwater loads.
AST M: American Society for Testing and Materials (ASTM International)
host pipe: the pipe: the old existing pipe to be modified.
AWWA: American AWWA: American Water Works Association BS: British BS: British Standards
partially deteriorated host pipe: pipe: a a host pipe that is relied upon to support soil and surcharge loads throughout its design life.
CIPP: cured-in-place CIPP: cured-in-place pipe DN: dimensional DN: dimensional number
po ly me r: a plastic material that can be thermoset (two-part polymer) or thermoplastic (one-part polymer) in nature.
I.D.: inside I.D.: inside diameter ISO: International ISO: International Organization for Standardization
polymer filler: filler : a relatively inert material added to a polymer to modify its strength, strength, permanence permanence,, or workin working g properties.
MSDS: material MSDS: material safety data sheet
pultruded carbon: a carbon: a relatively thin strip of polymer and carbon already cured and somewhat malleable to forming to the application geometry.
NDE: nondestructive NDE: nondestructive examination
NACE: National NACE: National Association of Corrosion Engineering NPS: Nominal NPS: Nominal Pipe Size OSHA: Occupational Safety and Health Administration OSHA: Occupational
reinforcement: high strength fibers imbedded in the polyreinforcement: high mer,, resul mer resulting ting in mechan mechanica icall pr prope opertie rtiess sup super erior ior to tho those se of the base polymer without the fibers.
SSPC-SP: Steel Structures Painting Council Standards SSPC-SP: Steel UV: ultraviolet UV: ultraviolet (radiation)
206
ASME PCC-2–2015
Part 5 — Article 5.1
PART 5 EXAMINATION AND TESTING Article 5.1 Pressure and Tightness Testing of Piping and Equipment (15)
1 DESCRI DESCRIPT PTION ION
(2) There may be limitations by device manufact ure ure r wit with h r ega egarr ds ds t o pr pree ss ss ur ur e, e, s ize ize,, an and d /or /or configuration. (3) Devices that leave markings on the internal surface should not be used when markings on the internal
(a) This Article provide providess gene general ral good practice practice for For selection of test determining the type of test, the test pressure, and the devicesand fortightness localized procedure for pressure testing of pressure equipment, including tubular heat exchangers, pressure pressure testing of vessels, and piping systems. This Article is intended for welded repairs of piping use in the following situations: see or Article (1) when asystems, complete vessel system5.3. is to be pressure tested (2) when a pressure vessel or system is isolated such that pressure testing is completed on a portion of the pressure vessel or system (b) General information regarding the various types of tests to choose from is provided, including application, benefits, and limitations. (c) Refer to individual individual repair articles of PCC-2 for any pressure or leak testing requirements or recommendations that should be followed.
(15)
surface cannot be tolerated (e.g., when such markings introduce cold working on stainless steel materials). (4) Depend Depending ing on thedevic thedevicee bei being ng used, used, axial axial stress stress typically may not be applied to the piping system in the same manner as applied by a pressure test to a complete system. (5) Flange assembly stresses may not be applied, depending on the method of local pressure testing being employed. (6) Localized pressure testing does not test the integrity of the final completed bolted joint. (e) This Article addresses pneumatic testing. Pneumatic testing is potentially hazardous, much more than hydrostatic testing due to the higher levels of potential energy in the pressurized system; therefore, all reasonable alternatives shall be consid alternatives considere ered d befor beforee this option is selected.
2 LIMIT LIMITAT ATION IONS S (a) Part 1 of this this Stan Standar dard d contain containss additio additional nal requi require re-ments and limitations. This Article shall be used in con junction with Part 1. (b) This Article shall be limited to use for field pressure or tightness testing of existing equipment and piping using either of the two fluid mediums, liquid or gas. (c) This Article shall not be used for vacuum testing of equipment or piping. (d) This Article addresses use of devices or methods to isolate a piping system, a piping component, or a pressuree vessel component [see para. 1(a)(2)] to perform pressur pressure or tightness testing. When using a device to isolate and test a weld, the following limitations should be considered: (1) The user is cautioned cautioned to ensu ensure re that use of any device is done in accordance with the requirements of its manufacturer manufacturer..
3 DES ESIG IGN N 3.1 Defini Definitions tions closure weld: the weld: the final weld connecting piping systems or components that have been successfully pressure tested in accordance with the applicable code of construction. hydrostatic test: a test: a pressure or tightness test where liquid, typically water, is the test medium. in-service leak test: a test using the process medium of the pressure equipment performed at start-up of the equipment. pneumatic test: a test: a pressure or tightness test where a gas, generally nitrogen or air, is the test medium. 207
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pressure test: a test performed to ensure the gross integrity of the pressure component on new pressure equipment, or on previously manufactured pressure and piping equipment that has been or is in service and that has undergone an alteration or repair to a pressure boundary(s) to ensure the gross integrity of the pressure component to the original code of construction. A pres-
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or when permitted by the applicable code of construction or post-construction code.
3.3 Test Type Type Selection The requirement for pressure testing can be found in the applicable code of construction or post-construction code. When no test is specifically referenced, Fig. 1 shall
sure testhmay beeumatic performed performe d ,with liquid (hydrostatic (hydr ostatic test), test), with wit gas (pneum (pn atic test) test), or a combin com binatio ation n of both (hydropneumatic test).
be used to determine the type of test to be performed.
tightness test: a test: a test that is performed to ensure overall leak tightness of the system or its connections before the process medium is introduced.
(a) A pressure test of equipment or a piping system should be considered if an alteration or repair has been perfor per formed med,, if the equ equipm ipmen entt hasbeen rerate rerated, d, or it needs needs to be recertified to determine integrity. (b) A pressure test may not be required for rerating equipm equ ipmen entt using using a hig higher her allowa allowable ble stress stress since since the ori origginal pressure test could be higher than the test pressure required for rerating. (c) Pressur Pressuree testing [or alternative alternatively ly,, tightness tightness testing; testing; see para. 6.3(a)] should be considered during routine inspections and after cleaning operations when the integrity integ rity of tube-to-tu tube-to-tubesh besheet eet joints is in question. question. Fol-
3.4 Pres Pressure sure Test Test — General
3.2 Reasons for Pressure Pressure and Tightness Testing Testing (a) The primary purpose of performin performing g a pre pressur ssuree test is to verify the integrity of a pressure system. This is especially true when welded repairs or alterations havee been performedon hav performedon the pre pressur ssuree boundary boundary.. Pressur Pressuree and tigh tightne tness ss testing testing are are not substit substitutes utes for pr proof oof testing testing a design. (b) Pressure or tightness tests can be used to check for pressure system leakage, especially in flanged joints. Tightness tests may be performed in conjunction with the pressure test. (c) Hydrostatic pressure testing can provide some mechanical stress relieving. This is accomplished when local regions of high stress, such as at stress concentrations and crack-like imperfections, undergo local yielding during the pressure test. Release of pressure then produces compressive residual stress in these regions, such that when pressure is reapplied, the operating stress is less than would have occurred otherwise. This can help mitigate the risk of brittle fracture when it is a consideration. Subsequent operation, especially at elevated temperatures, temperatures, can reduce or eliminate any benefit toward toward stre stress ss relief relief or brittle brittle fract fracture ure control. control. Hydr Hydroostatic pressure testing does not eliminate the need For selection of for postweld heat treatment, whethertest required by the applidevices for cable code of construction or by the user ’s requir requirements. ements. localized pressure See also para. 1.7 of Article 5.2. testing welded (d) The use of a device to isolate andoftest a weld of indepe ind epende ndent ntly ly of the com comple plete te pres prrepairs essur suree ves vesse sellpiping or sys system tem may be considered when pressure testing at a full test systems, see pressure in accordance with Section 6 is required (see Article 5.3. pa para ra.. 3. 3.3) 3).. It shou should ld be notedtha notedthatt us usee of de devi vice cess to isol isolate ate and test a weld should be used in conjunction with activity appropriate welding controls, in-process weld examinations, and NDE (see Article 5.2). (e) Tightness testing (1)may be considered when structural integrity does not need to be verified but when leak tightness must (2) be verified prior to start-up. (f ) In-service leak(3 testing can be considered when structural integrity does not need to be verified and the consequences of a leak during start-up are acceptable,
lowing the completion of the pressure test, the tubes should be inspected for buckling that may have occurred.
3.4.1 Exclusions Exclusions From Hydrostat Hydrostatic ic Test. Pressure testing should be performed hydrostatically unless one of the conditions in the following apply: (a) Usespecified of a test (a) The equipment, piping, and/or supports, includdevice for localized ing foundations, cannot adequately support the liquid weight. pressure testing be considered (b) Themay equipment or piping cannot be dried and traces of the test liquid may result in contamination of when any of the the system or its contents after returning to service. following conditions (c) The equipment or piping contains internal linings that couldexist: be damaged by the test medium. hydrostatic tatic 3.4.2 Pneum Pneumatic atic Test Con Condition ditions. s. If a hydros test cannot be performed per para. 3.4.1, then a pneumatic pressure test should be considered. (a) If a pneumatic pressure test would present unacceptable hazards such as risk of brittle fracture at the metal test temperature, then a substitution for pressure testing should be developed. (b) See also para. 6.2(d) for information regarding the need for risk analysis. analysis.
3.4.3 Localized Pressure Testing Consider Considerations. ations. (15) Use of a loca localize lized d press pressur uree testing testing device device may may be consid consid-ered when any of the following conditions exist: (a) Other welds in the system under consideration have already been tested or are exempt from testing. (b) Brittle fracture may be a consideration. (c) There is a need to minimize the number number of flanged joints to disassemble for the purpose of installing isolation blind flanges. flanges. 208
ASME PCC-2–2015
l a i f n l y o r n i a i t a a c v s s t i r e b d o c s p O i e r p a n u j
s s e n t h g i t t s e r t e d i s n o C
(see para. 3.4.3) d e z t i l c s i e a t c t a t o l s e r r o r u s e d d i y s s h e r n p o C
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Part 5 — Article 5.1
f g n o i t e u s l e b e i t a l c n e r i l i u p E s p a D s r N e p
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Part 5 — Article 5.1
(4)
(5) (6) (7) (8) (9) (10) (15)
ASME PCC-2–2015
(d) There is a need to minimize the amount of test fluid and/or avoid contamination of process items in the system, such as catalyst, linings, refractory, or other process equipment. (e) Complete isolation is not possible or practicable, such as when a piping system is welded directly to the nozzle of a pressure vessel.
mechanism. Consideration should be given to how each mechanism could manifest itself during a pressure test. Section 7 provides references that provide considerations for damage mechanisms. (1) The inspection records should be reviewed for thinning beyond the specified limit. If thinning has occurred beyond the specified corrosion allowance, an
Sole use RT or other volumetric examination is not(f)desired orof practicable. (g) There is a need to minimize the amount of insulation abatement and reinstallation. (h) There are potential consequences or additional risks associated with test fluid remaining in the system following followi ng completion completion of a pres pressure sure test. (i) There is a need to minimize disassembly and/or removal of system components. (j) A repair versus an alteration has been performed. (See Article 5.2 for information information on repair repair and altera alteration.) tion.)
engineeri engin eering ngdata. evaluatio evaluation n shall be performed performed using current current inspection (2) The material may have been subjected to damage due to temperature or process exposure. If evidence of damage is found by inspection, an engineering evaluation shall be performed using current inspection data. (3) The component/system may have been damaged by mechanical means such as high vibration. Consideration sider ation should be given to analy analyzing zing the syste system m for areas where damage could occur and then inspecting these areas prior to testing to look for evidence of damage. (b) In order order to redu reduce ce the ris risk k of bri brittl ttlee fractu fracture re durin during g thetest, thetempe thetemperat ratur uree of themetal durin during g thepres thepressur suree test of pressure vessels should be maintained at a minimum of 17°C (30°F) above the minimum design metal temperature (MDMT) (as shown on the Manufacturer’s Data Report). (1) If the MDMT is unknown, the minimum allowable temperature (MAT) of the component or system should be determined determined using a fitness-for-s fitness-for-service ervice evaluation. (2) If a vessel made of low alloy steel has been subjected to thermal treatment or service temperatures over 370°C (700°F), an upward shift in the ductile-to brittle transition temperature may have occurred. This loss of toughness may not be readily apparent during operation; however, the vessel may be susceptible to brittle fracture. Therefore, the temperature used for the pressure test may need to be determined by a fitnessfor-service evaluation.
(b) Test devices for localized
3.4.4 Nondestructive Examinati Examination on Considerations. Considerations. pressure testing shall be Nondestructive examination may be considered in lieu andor installed in in of pressure testing toselected verify repairs alterations some instances (see Article 5.2). Thiswith may Article require the accordance 5.3 use of tightness testing as well.
3.5 Documentati Documentation on A pressure test record form should be prepared prior to the pressur pressuree test and completed completed upon acceptance acceptance of the test by the owner or the owner’s designated representative. A sample record form is provided in Mandatory Appendix I.
4 FAB FABRIC RICA ATION TION Within the context of this Article, this section is not applicable.
5 EXA EXAMIN MINAT ATION ION
6.1 Hydrostatic Pressure Test Test of Pressure Vessels or Piping Systems
(c) When pressure testing piping systems, the ambien entt tem temper peratu ature re sho should uld be gr great eater er tha than n 2°C(35°F) 2°C(35°F).. When When pressure testing at colder temperatures, the use of an antifreeze antifr eeze solution should be consider considered ed as the test medium med ium to prev preven entt fr freez eezing ing;; howeve howeverr, the met metal al tem temper per-ature should be kept above the ductile-brittle transition temperature. Additional guidance regarding pressure testing at cold temperatures may be found in the references listed in section 7 of this Article. (d) The vessel and its supports and the foundation and/or the piping system and its supports and support structures should be evaluated to determine if they will adequately support the weight of the test medium. (e) Pressure gages used for recording test pressures should be calibrated and located at the highest point on
(a) The andoperational in-service inspection records along withfabrication any necessary records should be reviewed prior to testing to determine if the pressure component/system has experienced a credible damage
the vessel or on the piping system. The19.2 gages should meet the requirements of ASME PTC or similar gage perfo performan rmance ce standard, standard, and be corr corrected ected as require required d to compensate for the static head present in the system.
Within the context of this Article, visual examination shall be performed during the pressure, tightness, or in-service leak test to determine if any leakage is occurring during the test. When visual examination is not possible, such as for underground piping, monitoring of system pressure for pressure drop during tightness or in-service leak test may be substituted when approved by the owner. See also paras. 6.1(t)(8) and 6.2.1.3(c) regarding safety practices.
6 TE TEST STIN ING G (15)
210
When calculating the stored energy for a vessel, the total volume shall be considered. When calculating the the stored energy of a piping system, a maximum volume based on a length of 8 pipe diameters ASME PCC-2–2015 PCC -2–2015 may be considered for any single failure analyzed.
(g)
NOTE to Editor: This becomes the last Part 5 Article sentence of—(e) . 5.1
air meeting the requirements of Class 1, 2, or 3 air per ISO 8573-1:2010 should be used with a dew point ranging fr from om −20 −20°C °C to −70 −70°C °C (−4 (−4°F °F to −94 −94°F) °F).. Cau Caution tion sho should uld be used when air is used in any system that cannot be verified as being free of hydrocarbons since this could result in the formation of an explosive mixture. When necessary, the design service fluid can be used for pneu-
(4) the amount of nondestructive examination performedon we formedon welds lds tha thatt ha have ve notprev notpreviou iously sly bee been n sub subjec jected ted to a hydrostatic or pneumatic pressure test (5) other simultaneous inspection methods being performed during the pressure test such as Acoustic Emission Emiss ion (AE) testing (6) pressure wave from potential blast
matic pressure testing.and in-service inspection records (c) The fabrication along with any necessary operational records should be reviewed prior to testing to determine if the pressure component/system has experienced a credible deterioration mechanism. mechanism. Cons Considera ideration tion should be given to how each mechanism could manifest itself. (1) The inspection records should be reviewed for thinning beyond the specified limit. If thinning has occurred beyond the specified corrosion allowance, an engineering evaluation shall be performed. (2) The component/system may have been damaged by mechanical means such as high vibration. Consideration should be given to inspecting the entire system prior to testing to look for evidence of damage. (d) Compo Componen nents ts fabric fabricated ated from britt brittle le mater materials ials such as cast iron and ductile iron shall not be pneumatically pressure tested unless the following requirements are adhered to: (1) the pressure test does not exceed MAWP (2) additional NDE, such as Acoustic Emission (AE) testing, is performed along with the pressure test (3) the procedures from para. 6.2.1 are followed (e) The maximum calculated stored energy of any vessel or piping system being pneumatically pressure tested should not be greater than 271 000 000 J (200,000,000 ft-lb). If the calculated stored energy is greater than 271 000 000 J (200,000,000 ft-lb), then one of the following shall occur: (1) The system shall be divided into smaller volumes such that each subsystem has a stored energy not greater gre ater than 271 000 000 J (200,0 (200,000,000 00,000 ft-lb). (2) A min minimu imum m dis distan tance ce sha shall ll be cal calcul culate ated d per Mandatory Appendix III, eq. (III-1), and this distance shall be adhered to. (3) A barricade per para. 6.2(g) shall be installed. (f) A detailed hazard analysis should also be performed to evaluate the risk associated with the release of sto store red d ene energ rgy y. SeeManda SeeMandator tory y App Appen endix dix IV for con consid sid-erations eratio ns rela relative tive to risk evaluation. evaluation. Facto Factors rs to consid consider er in this analysis should include: (1) any damage mechanisms identified by review of fabrication fabrication or in-se in-service rvice inspection inspection rec records ords along along with operational records (2) the MDMT of the components being pressure tested, and its relative comparison to the test temperature to address the risk of brittle fracture (3) the stress level of the system while undergoing a test
(7) sizedistance of poten potential tialtravel, fragment fragm ents resulting ulting fromfailure of system, of ands res existence of barriers (h) sufficient to stop fragment projectiles (g) For pressure tests where the risk of injury from potential poten tial fragm fragment ents, s, shock shockwa waves, ves, or other conse consequenc quences es of any pressurized system failure is determined to be unacceptable, a limited access area and pressure control point should be established. The minimum distance from fro m thebound theboundary ary of thi thiss ar area ea to thepres thepressur surize ized d com compoponent should be calculated according to the procedure of Mandatory Appendix III. When Whe n the spa spacing cing req requir uireme ement ntss des describ cribed ed in Mandatory Appendix III are not achievable, consideration should be given to the design, fabrication, and installation of an alternative barricade capable of withstanding the blast of stored energy within the system. See also para. 6.2(e). (i) (h) Overpressure relief protection shall be provided. The set pressure of a pressure relief device should be not more than the greater of (1) the test pressure plus 70 kPa (10 psi), or (j) (2) 110% of the test pressure (i) The test pressure for a pneumatic pressure test for equipment should be according to the original code of construction, considering also any subsequent engi(k) neering analysis as deemed necessary. (j) If the re requi quire reme ment ntss of the ori origin ginal al cod codee of con constr strucuction are not available, the test pressure for a pneumatic pressure test for pressure vessels shall be Pt
p
1.1
P
Sat Sdt
(3)
where
(h)
P
Pt Sat
Sdt
p
p
p
p
maximum allowable working pressure from the Manufacturer’s Data Report. If unknown, use the vessel’s design or rated pressure. test pressure to be used allowable stress at test temperature from the applicable code of construction for the material of which the component under consideration is constructed allowable stress at design temperature from the applicable code of construction for the material of which the component under consideration is constructed
p
Sat/Sdt
NOTE TO EDITOR: 213 Begin a new clause (f) starting as follows:
1.1
p
rat ratio io of allowa wable ble stress thelowest thelowes t va value lue shall beallo used in str eq.esses; (3)es;for all materials considered the test factor
(f) If the calculated stored energy is greater than 271,000,000 J ... " (f)
Part 5 — Article 5.1
ASME PCC-2–2015
(l)
(k) If therequ therequire iremen ments ts of theoriginal theoriginal cod codee of constr construcuction are not available, the test pressure for a pneumatic pressure test for piping systems shall be Pt
where P Pt 1:1
p
1.1 P
(4)
p
the internal design pressure of the piping
p
system the test pressure to be used the test factor
p
If pressure loss is observed, reduce pressure to 25% test pressure and check for leaks. If necessary, release pressure and perform necessary repairs. Return to Step 1. (b) Once full test pressure is reached, block supply and observe pressure gage for a minimum of 10 min. (c) Reduce system pressure to the following applica ble pressure: pressure: (1) the test pressure divided by the test factor for vessels [see eq. (3)]. If there is no test factor available, use 4/5 test pressure. (2) design pressure for piping.
(m)
(l) The stored energy of the equipment or piping system under pneum pneumatic atic pressure pressure shoul should d be calcul calculated ated and converted conv erted to equivalen equivalentt pound poundss of TNT (Trinit (Trinitroto rotoluene luene)) using the equations shown in Mandatory Appendix II. The value calculated may be used for alternative safe distance calculations as per Mandatory Appendix III. The minimum safe distance shall be the greater of the distance required by Mandatory Appendix III, para. III-1(a) or as calculated by eq. (III-1). See also Table III-2 when fragments are to be considered.
6.2.1.4 6.2. 1.4 Step Step 4 (a) Conduct a complete inspection for leakage of the vessel or piping system, or both, at locations such as flanges, weld joints, and threaded connections. NOTE: It is assumed assumed that the integ integrity rity of the pre pressuri ssurized zed system has been proven by para. 6.2.1.3(b) and the barricades required by para. 6.2(e) can be safely passed.
(b ) If no leakage is discovered, release system pressure.
NOTE: The storedenerg NOTE: storedenergy y va valueof lueof 27 2711 000 000 000J (20 (200,0 0,000 00,00 ,0000 ft-lb) ft-lb) is equivalent to an explosive energy of 127 lb of TNT. Risk evaluation may also be required; see Mandatory Appendix IV and para. 6.2(d).
(c) If leakage that is not acceptable is discovered, discovered, relieve all system pressure and repair. Repeat Steps 2 and 3.
6.2.1 Pneumatic TTest est Procedures. The items specified in paras. 6.2.1.1 through 6.2.1.5 (Steps 1 through 5) should be considered when developing pneumatic pressure test procedures for vessels or piping systems. 6.2.1.1 Step 6.2.1.1 Step 1 (a) Raise pressure to the lesser of 170 kPa (25 psi) or 25% of test pressure. (b) Block in supply and hold for 10 min. (c) Visually inspect system for leaks. (d) If leaks are discovered, release pressure, repair, and return to Step 1. (e) If no leaks are discovered, proceed to Step 2. increase system pres6.2.1.2 Step 6.2.1.2 Step 2. Gradually increase sure to 50% of the test pressure as follows: (a) Incr Increa ease se from from pres pressu surein rein Step Step 1 by 350 350 kPa kPa (50 (50 ps psi) i) or to 35% test pressure, whichever is greater. Hold for a minimum of 3 min to allow strains to equalize. Continue to increase by 350 kPa (50 psi) increments until the system pressure is at 50% test pressure. (b) Hold at 50% test pressure for a minimum of 10 min. Observe pressure gage for loss of system pressure. If pressure loss exceeds 10% of test pressure, the system pressure should be reduced to 25% test pressure and check for leaks. (c ) If no loss of pressure pressure is detected, subject subject to approval of the inspector, proceed to Step 3.
6.2.1.5 Step 6.2.1.5 Step 5. After completion completion of the test, test, the vessel or piping system, or both, should be restored to its design condition. This includes, but is not limited to, the following: (a) All flanged joints blinded for pressure pressure testing should be reassembled with new gaskets and tightened in accordance with applicable specifications. Consideration should be give to ASME PCC-1 guidelines. (b) Vent and bleed connections that were installed for testingpurpo testingpurposesonly sesonly should should be plug pluggedusing gedusing mate materia rials ls and methods per the applicable specification. Consideration should be given to seal welding when necessary.
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6.3 Tight Tightness ness Test Test
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(a) A tightness test may be performed to detect leaks at various locations within a pressure system. It may be performed on systems that have previously been pressuree tested sur tested,, for clo closur suree we welds lds of piping piping sys system tems, s, on tubetubeto-tubesheet joints, and on systems exempted from hydrostatic hydr ostatic or pneumatic pneumatic testing. testing. ASME BPVC Section V, Article 10 provides information on a variety of leak testing methods. (b) A sensitive leak test per ASME B31.3 is the preferred method for conducting a tightness test. (c) The applied test pressure for vessels and piping should not exceed 35% of the design pressure. However, However,
6.2.1.3 Step 3 (a) Gradually increase system pressure in increments of 10% of test pressure. At each increment, block supply and observe pressure gage for 5 min.
leakage at when flanged joints may beleak evident at much lower pressures using sensitive detection methods; therefor ther efore, e, the minim minimum um test pres pressure sure shoul should d be specified specified which whi ch ena enable bless thetest sensiti sensitivit vity y requir requireme ement ntss to be met met.. 214
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(d) Where the consequences of leakage of the process medium are acceptable, an in-service leak test may be performed as a tightness test using the process medium during the start-up of the system. (15)
6.3.1 Pneumatic Tightness Test Procedures. The items specified in paras. 6.3.1(a) through 6.3.1(f) should be considered consi dered when developing devel oping pneuma pneumatic tic tight tightness ness test procedures for vessels or piping systems. (a) Clean, dry, oil-free air should be used as the test medium, except in systems which cannot be verified as free from hydrocarbons. For this situation, nitrogen should be used as the test medium [see para. 6.2(b)]. (b) To minimize the stored energy of a system, the maximum test pressure should be not more than 35% of the design pressure of the vessel or piping system. The test pressure should be no less than the lesser of 105 kPa (15 psi) or 25% of the system design pressure. (c ) The system system press pressure ure sho should uld be gra gradu dually ally increased until the system pressure is the lesser of 170 kPa (25 psi) or 25% of the test pressure. Hold at this pressure long enough to conduct a preliminary inspection for leaks.
Part 5 — Article 5.1
ASME Boiler and Pressure Vessel Code, Section VIII, Division 1 — Unfired Pressure Vessels ASME B16.5, Pipe Flanges and Flanged Fittings ASME B31.3, Process Piping (See also Appendix F therein for considerations of damage mechanisms.) ASME PCC-1, Guidelines for Pressure Boundary Bolted Flange Joint Assembly ASME PTC 19.2, Pressur Pressuree Measurem Measurement ent,, Inst Instrume ruments nts and Apparatus Publisher: The American Society of Mechanical Engineers (ASME), Two Park Avenue, New York, NY 1001610016-599 5990; 0; Order Order Depart Departmen ment: t: 22 Law Drive, Drive, P.O. Box 2900, Fairfield, NJ 07007-2900 (www.asme.org) ISO 8573-1, Compressed Air — Part 1: Contaminants and purity classes Publisher: International Organization for Standardization (ISO), Central Secretariat, 1, ch. de la Voie-Creuse, Voie-Creuse, Case postale 56, CH-1211 Gene` ve 20, Switzerland/ Suisse (www.iso.org) (www.iso.org) Recommended Practice SNT-TC-1A, Recommended SNT-TC-1A, Personnel Personnel Qualification Qualific ation and Certification Certification in Nondes Nondestructive tructive
(d) System pressure should be gradually increased in Testing ANSI/ASN ANSI /ASNT T CP-1 CP-189-2 89-2006, 006, ASNT Stan Standar dard d for increments of 10% of test pressure, holding for 30 sec Qualification Qualific ation and Certification Certific ation of Nondestructive Nondest ructive to 1 min at each increment. Hold at final test pressure Geng, Jihui and Thomas, Kelly. "Evaluations of Pipe Loads from Blast Ruptures". ASME Testing Personnel and complete a thorough inspection for leakage using 2017 Pressure Vessel and Piping Conference. PVP2017-65186: Honolulu, HI, USA, July th hee Ga Gass an and d Bu ub bb ble le t e sstt m eett hod hod s pe pe cifi cifiee d in Publisher: American Society for Nondestructive Testing 16-20, 2017. V, DOI 10.1115/PVP2017-65186. ASME Section Article 10, or other method of equal (ASNT), 1711 Arlingate Lane, P.O. Box 28518, http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx? or better sensitivity. Columbus, OH 43228 (www.asnt.org) (e) If leakage is discovered and a joint needs to be articleid=2660516&resultClick=3 “NDT Solution: Worried About Leaks? Don’t Paint tightened, reduce system pressure to the lesser of 50% Before Hydrotesting,“ Jon E. Batey, Materials of test pressure or 170 kPa (25 psi) and tighten. Evaluation, Volume 51, Number 9, September 1993, (f) After completion of the test, the vessel and/or pp. 980-982. piping system should be restored to its operating condition. Welding Research Council Bulletin 488, Damage Mechanisms Affecting Fixed Equipment in the Pulp and Paper Industry, Jonathan D. Dobis and REFERE RENC NCES ES (15) 7 REFE David C. Bennet, July 2, 2004. API RP 571, Damage Mechanisms Affecting Fixed Welding Research Council Bulletin 489, Damage Equipment in the Process Industry Mechanisms Affecting Fixed Equipment in the API RP 579, Fitness-for-Service Refining Industry, Jonathan D. Dobis, J. E. Cantwell API RP 580, Risk Based Inspection and Martin Prager, July 2, 2004. Publisher: Publishe r: American American Petr Petroleum oleum Institute (API), Welding Research Council Bulletin 490, Damage 12 1220 20 L S tr tr ee ee t, t, NW, NW, Was hin hingt gton on , DC 20 2000 0055 Mechanisms Affecting Fixed Equipment in the Fossil (www.api.org) Electric Power Industry, Jonathan D. Dobis and David N. French; July 2, 2004. ASME Boiler and Pressure Vessel Code, Section II, Publish Publ isher: er: Welding elding Resear Research ch Council Council (WRC), (WRC), Part D — Properties P.O. Box 201547, 201547, Shaker Shaker Heights, Heights, OH 4412 44120 ASME Boiler and Pressure Vessel Code, Section V — (www.forengineers.or (www .forengineers.org/welding-rese g/welding-research-council) arch-council) Nondestructive Examination
American Table of Distances for Storage of Explosives Publisher: Institute of Makers of Explosives 1120 19th Street NW, Suite 310, Washington D.C 20036 (www.ime.org) 215
Part Part 5 — Ar Arti ticl cle e 5. 5.1, 1, Mand Mandat ator ory y Ap Appe pend ndix ix II
AS ASME ME PCC PCC-2–2 -2–201 015 5
Article 5.1, Mandatory Appendix II Stored Energy Calculations for Pneumatic Pressure Test The stored energy of the equipment or piping system should be calculated and converted to equivalent kilograms (pounds) of TNT (Trinitrotoluene) using the following equations: E
p
where E k Pa
p
p
p
Pat V
p
p
1/(k k − − 1) 1/(
Pat
where E Pa Pat V
p
p
p
p
− 1)/k] )/k] V 1 − (Pa/Pat)[(k − 1 (II-1)
stored energy, J absolute atmospheric pressure, 101 000 Pa absolute test pressure, Pa total volume under test pressure, m3
For U.S. Customary units using air or nitrogen as the test medium (k (k 1.4), this equation becomes p
stored energy, J (ft-lb) ratio of specific heat for the test fluid absolute atmospheric pressure, 101 kPa (14.7 psia) absolute test pressure, Pa (psia) total volume under test pressure, m 3 (ft3)
E
p
360 Pat
V 1 − (Pa/Pat)0.286
and TNT
When using air or nitrogen as the test medium (k 1.4), this equatio equation n becomes becomes
p
E (lb) 1,488,617
p
E
p
2.5 Pat
0.286
V 1 − (Pa/Pat)
where E Pa Pat V
(II-2)
p
p
p
and
p
TNT
p
E (kg) 4 266 920
(II-4)
(II-3)
stored energy, ft-lb absolute atmospheric pressure, 14.7 psia absolute test pressure, psia total volume under test pressure, ft3
See also paras. 6.2(e) and 6.2(f) of Article 5.1.
When calculating the stored energy for a vessel, the total volume shall be considered. When calculating the stored energy of a piping system, a maximum volume based on a length of of 8 pipe diameters may be considered for any single failure analyzed.
218
(II-5)
ASME PCC-2–2015
Part 5 — Article 5.1, Mandato Mandatory ry Appendix IV
Article 5.1, Mandatory Appendix IV Risk Evaluation Considerations for Pneumatic Pressure Test IV-1 INTRODUCTION (a) a new austenitic stainless steel piping system that has been hydrostatically tested during shop fabrication with wit h the exc excepti eption on of four four final final field field assemb assembly ly cir circum cumfer fer-ential butt welds. The piping system has a total volume that results in an energy level greater than 271 000 000 J (200,000,000 ft-lb); however, it is not feasible to separate the piping system into smaller sections for testing, nor is it feasible to install blast barriers. By performing volumetric metr ic examination examination such as UT or RT and determining determining the field welds are free of rejectable indications, the risk associated with a full pneumatic pressure test of this system may be deemed acceptable. (b) an existing carbon steel vessel with an MDMT rating of −45°C (−50°F) into which a new nozzle had been installed following all requirements requirements of the original code of construction. The vessel has a total volume that results in an energy level greater than 271 000 000 J (200,000,000 ft-lb); however, it is still desired to perform a pressure test to check the integrity of the weld and obtain the other benefits of pressure testing. It is not feasible to install blast barriers. By performing volumetric examination such as UT on the nozzle attachment weld and determining the weld is free of rejectable indications, along with verification by inspection that the vessel is in a like-new like-new condition, the risk associated with a full pneumatic pressure test of this vessel may be deemed acceptable.
When considering the risk analysis factors listed in para. 6.2(f), it should should be remember remembered ed that risk is a two-dimensional combination of probability (or likelihood) hoo d) andconseque andconsequence nce.. Ris Risk k is themeasu themeasureof reof thepotential for harm or loss (i.e., hazard) that reflects the likelihood (or frequency) and severity of an adverse effect effe ct to health, health, property property,, or the env environ ironmen ment. t. If prob probabilability and consequence are defined quantitatively (i.e., numerical values are assigned), risk is the product. Risk
p
Probability
Consequ sequen ence ce
(IV IV-1 -1))
In a qualitative assessment, a matrix is typically used to combine probability and consequence. Consideration should be given to the level of risk that is acceptable when whe n perfor per ming g pneuma pneumatic ticdetermining tests. tests. Ref Refer eren ence ce API RP 580 for use offormin risk assessment in the acceptable levels leve ls of risk associated associated with pneumatic testing. In reviewing eq. (IV-1), it is clear that even though the consequence may be significant, if the probability is very low, the risk may become acceptable. For example, the consequence of an airliner crashing is significant in that it will most likely result in serious injury or death to the passengers along with major damage or total loss of the aircraft. However, the probability of the airliner crashing is very low; thus, the public accepts the risk associated with airline travel. Risk considerations can be applied to pneumatic testing also. Examples may include
IV-2 PNEUMATIC TEST RISK CONSIDERATIONS
(c) When considering the volume of piping to complete stored energy calculations, the use of 8 pipe diameters may not be sufficient. (1) Brittle failure or failure along the length of a poor longitudinal weld seam, where the actual opening may be instantaneous and the release of energy larger than that as calculated by 8 pipe diameters (2) Installations where the pipe or pipeline is not restrained and can become a projectile; see Table III-2.
IV-3 SYpage SYSTEM STEM VOLUME CONSIDERATIONS InsertPIPING from next
221
IV-3 PIPING SYSTEM VOLUME CONSIDERATIONS IV-3 STORED ENERGY IN PIPING SYSTEMS
A schematic illustration of of the pipeline rupture leading to burst explosion is is shown in Figure 1. The volume of gas that should be included within the stored energy calculation is not just the volume contained within the pipe length that has ruptured, but should include a section of each end of pipe that is starting to depressurise, given as "d" in Figure 1.
Figure 1: 1: A schematic diagram of a pipeline burst, showin g the flow of g as within th e pipes. The The distance d, represents represents the length of i ntact pipe, from whi ch gas can contr ibute to the initi al stored energy energy calcul ation of the burst explosion. The distance d can be calculated by considering the speed that information about the loss of containment can travel down the pipe. When W hen the rupture occurs, the shock wave of the rupture travels down the pipe at the speed of sound of the compressed gas. The shock wave for this type of explosion has a typical signature shape with a steep rise time. The exact rise time would vary for each incident, but will be less than the measured rise time within a deflagration explosion (which has a shallower profile initially) and is consequently less than 10 milliseconds. The basis for total piping volume vary and are summarized below: Baker Model
8 pipe diameters*
TNT Model
11 meters of pipe
Major Refining Operator
18 meters of pipe
Major Engineering Firm
200 pipe diameters
*See “Evaluation of Blast Loads from Pipe Ruptures”, PVP2017-65186.
Article 5.3 Test Devices for Localized Pressure or Tightness Testing of Welded Repairs
(insert new Article record# 13‐854)
See attached PDF file: 13-854.pdf
