Inspection & Maintenance of Drill Pipe A general guideline to maintaining drill strings
www.odfjellwellservices.com
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Inspection & Maintenance of Drill Pipe
Contents 3. Introduction
25. Why use thread compounds?
4.
26. Pipe storage
Description of a common inspection
6. Measurements
27. Preservation
7.
Magnetic particle inspection
28. Recommendations
8.
Ultrasonic testing
29. Thread compounds
9.
Electromagnetic inspection (EMI)
31. Inspection standards
11. What to look for when inspecting
33. Inspection companies
14. Drill pipe repair
34. A general view on the necessary certifications
21. Repair companies
22. Documentation & traceability
37. Approval certification
24. Presentation & storage
38. Documentation / Reporting
for a thread inspector
Inspection & Maintenance of Drill Pipe
Introduction This gives an introduction to the processes involved in inspecting and repairing of used drill pipe. We will list the most common inspection specifications, describe the differences between the standards and describe the process of being certified to the various standards. We will also describe the various repair scenarios on drill pipe and the certification process involved for companies that perform repairs.
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Inspection & Maintenance of Drill Pipe
Description of a common inspection When the drill pipe is received for inspection, all joints should be properly cleaned both internally and externally.
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Inspection & Maintenance of Drill Pipe
The following steps are mandatory:
Visual thread inspection (VTI) VTI is a non-destructive inspection method that is based on the inspector using his eyes and hands. Any reduced eyesight might cause the inspector to miss vital flaws.
Example of check with a profile gauge
Tools required • Flashlight • Profile gauges • Magnifying mirror
Example of use of finger tips on a VTI inspection
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Inspection & Maintenance of Drill Pipe
Measurements On a VTI it is normal to make all vital measurements on the connections. The results need to match the standards given in the inspection specification.
Example of OD gauge of tube
Tools required • Various calipers (slide caliper etc.) • Thread gauges
Example of a check with a slide caliper
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Inspection & Maintenance of Drill Pipe
Magnetic particle inspection (MPI) Magnetic particle method is a non-destructive testing method revealing material defects in the surface, and just below the surface, in ferromagnetic (magnetic) materials. A magnetic field is applied to an object. The magnetic field will penetrate the surface of the object. Any errors in the surface will alter the power of the magnetic field lines. These power lines outside and around the damage forms(delete s) a leakage field. This leakage field can be detected by adding iron particles (in powder
Example of applying fluorescent magnet powder
form) on the surface. These particles clump together in and around the leakage field.
Magnet field
Leakage field Depth errors Magnet field
Shallow imperfection
Example of connection checked with UV light
Tools required An object can be magnetized with several methods: • Coil • AC Yoke • Direct current flow
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Inspection & Maintenance of Drill Pipe
Ultrasonic testing Ultrasonic testing is a nondestructive testing method that uses radio frequencies to determine a materials entirety. Impulse-echo method is the most used method in industry. An array of transducer one sound waves are sent into the material, penetrating it at a constant speed (the speed of sound of the material). The sound waves are reflected from the back wall of the object back to the probes. Any imperfections in the material will appear as peaks between the initial and the reflecting echo.
Transmission pulse/Start echo Back wall echo
Defect
Reflector Object/Workpiece
0
2
Ultrasonic screen
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8
10
Ultrasonic measurement determining wall thickness.
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Inspection & Maintenance of Drill Pipe
Electromagnetic inspection (EMI) Primarily the eddy-current and flux-leakage methods are used to detect imperfections. NOTE: Electromagnetic “Inspection Systems” made for use in the field sometimes include equipment for performing additional inspections or services. Source: API RP 5A5, Field Inspection of New Casing, Tubing, and Plain-end Drill Pipe, Reaffirmed August 2010. Global
Examples of EMI unit
Examples of EMI unit
Example of EMI probes
Example of EMI control screen
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Inspection & Maintenance of Drill Pipe
Every inspection is to be finalized with a documentation of the service/inspection; the inspection report. Any damage that cannot be repaired in the field, has to go to a workshop.
Menus Main Tubular DP Related Menu Menu Detail W.O.
Drillpipe Summary Report ID
Date
Customer Ref.
Customer
P.O. No
Rig
Location
Work Order Spec.
SPECIFICATIONS
Well No. NS-2
VTI Only Spec. EQUIPMENT
SURFACE CONDITION
DS 1 Cat. 4
Show all records
HDLS
Black/White Fluorescent
EMI Scope No.
End Area Tool No.
Yoke No.
Thick. Gauge No.
UV Light No.
Coil No.
Hardbanding: Present Plastic Coated:
CLEANING
Cat. 5
Receipt Insp. Spec.
TBA*
Yes
Internal Qty
No
Pin
Box
External Qty
1400 bar 2000 bar Special
Hard Pollution
Hard Pollution
Weight
Lbs/Ft
Tube OD
Threads
Nom Wall
Nom TJ OD
10.04.2015 Modification Date 10.04.2015
Wear Report Wear Report - Overview
Range
Grade Tube
Nom TJ ID
Min TJ OD
Repair - Hardbanding
Send to Trio
Repair - Machining
Send to NOS
INSPECTION RESULTS CLASS
TUBE TOOL JOINT
Premium
RECUT
SHOP REFACE
FIELD REFACE
PLASTIC COATING
HARDBANDING SER. NO. BENT PIN BOX RESTAMP
Joints
Joints
Total
Ok
OK
x1
Class2
Pin
Pin
Pin
Damaged
XT300 Rep.
x2
Scrap
Box
Box
Box
No Coat.
OTW12 Rep.
Number of Joints Inspected Number of Joints Require Shop Repair
(
Re-Cut with HB Damage)
Number of Hardbanding Repair
(Not Included In Recut Joints)
Number of Class2 & Scrap Number of Joints Ready For Use
Scrap per W.O. Wall Thickness Wear Preinvoice
Field Repair
Hours
Grinding Tongmarks and Slipcuts
Hours
Protectors Supplied By Euroincon
Qty.
Make Preinvoice
Misc.
Relookup
Number of Premium After Repair
Change Work Order
Comments
TAM Import
TAM - Make Field Copy NDT Level II Inspector
*TBA - To be applied
CERT. NO. NAME :
Odfjell Tag No List
Reports
MATERIAL Lot No.
admin Modifier Name admin
New Record - Detail
ID Condition
2000 bar Special
Creator Date
New Record - Detail
Dope Applied
1400 bar
Creator Name
We hereby confirm that the above material has been inspected in accordance with specified insp. proc., P.O. and Euroincon W.O.
Example of an inspection report
Field Copy
Print - Field Copy
Serial No TAM
Serial No TIM
Pages TAM Pages made
1
(Set to 1 if delete detail)
Restore
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Inspection & Maintenance of Drill Pipe
What to look for when inspecting Here are some examples of damage typical to connections. This is everyday damage that cannot be repaired on site.
Crack indications in thread
Crack indication in box connection
Crack indication in outside upset
Galled thread
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Inspection & Maintenance of Drill Pipe
What to look for when inspecting
Pulled thread
Overtorqued threads
Galled seal
Stabbing damage to shoulder
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Inspection & Maintenance of Drill Pipe
What to look for when inspecting
Pitting/corrosion in pin SRG
Washout in connection
Washout in connection
Inspection & Maintenance of Drill Pipe
Drill pipe repair Whether you need to take the pipe to a repair shop or it can fixed in the field, is dependent on the degree of damage to the joints.
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Inspection & Maintenance of Drill Pipe
Field repair Grinding Double shouldered connections or severe shoulder damage, require a shop reface.
Grinding Pin threads
Grinding Box threads
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Inspection & Maintenance of Drill Pipe
Field reface Reface of a damaged connection shoulder is done with a special shoulder dressing tool. There are several types available on the market, but the same principle applies to all of them. A refaced shoulder should be flat and at right angles to the threads.
Refacing tool
Damaged shoulder
Refacing of shoulder
Refaced shoulder
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Inspection & Maintenance of Drill Pipe
Shop reface Double shouldered connections or severe shoulder damage, require shop reface.
Before shop reface
After shop reface
Recut of pin
Recut of Box
Shop recut A full repair (recut) of a connection has to be done in a proper and authorized workshop.
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Inspection & Maintenance of Drill Pipe
Benchmark Both pin & box connections are marked after a recut. This is to determine the space left for (future) reface. The most common way to mark this is either with a stamp, or a machined groove.
Stamped mark
Machined groove
Cold working
LOAD
After recut, the
ROLLER
thread root
AFTER ROLLING, THESE FIBERS REMAIN IN COMPRESSION
is cold rolled to compress the fibers. This will restrict any evolvement of fatigue.
Cold Working tool
Principle sketch
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Inspection & Maintenance of Drill Pipe
Copper sulfating A copper sulfated
Both copper sulfating
shoulder will last
and phosphatization
longer. This is done
is done to prevent
after the reface/shop
galling and provide
reface to reduce the
corrosion resistance.
risk of galling and corrosion.
Copper sulfated shoulder
Phosphatization Phosphatization of connections is done in a chemical bath after a recut. This process increases the durability of the connections.
Chemical bath
Straightening of bent drill pipe
Due to several reasons, drill pipe can be bent during drilling operations. A bent pipe is straightened without the use of preheating. A hydraulic press is to be used.
Hydraulic press
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Inspection & Maintenance of Drill Pipe
Hardbanding Worn out hardbanding needs to be grinded down before a new one is welded on. Some materials will not blend properly, and the hardbanding has to be removed completely before a new one is welded on.
Worn out hardbanding
Recoat Internal Plastic Coating (IPC) is designed to enhance the performance of tubulars by reducing wear and corrosion, and improving hydraulic efficiency. Coating
Rewelded
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Inspection & Maintenance of Drill Pipe
Repair companies A proper workshop for repair and rework on the drill pipe should have a quality, well managed system.
Here’s a sample of a certified quality system.
For fabrication or repair of a connection, the machine shop needs to be licensed for that particular type of connection. Here’s a sample of such a type of certificate.
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Inspection & Maintenance of Drill Pipe
Documentation and traceability All repairs must be traceable. It starts with the
The Repair report states the individual (unique) equipment number for a
inspection and must follow the whole process
repair, and also what needs to be repaired (highlighted on report).
until the finalized repair. Sample of Inspection Report for drill pipe;
Menus Main Tubular DP Related Menu Menu Detail W.O.
Drillpipe Summary Report ID
Date
Customer Ref.
Customer
P.O. No
Rig
Location
Work Order Spec.
SPECIFICATIONS
Well No. NS-2
VTI Only Spec. EQUIPMENT
SURFACE CONDITION
DS 1 Cat. 4
Show all records
HDLS
Black/White
Receipt Insp. Spec.
Fluorescent
EMI Scope No.
End Area Tool No.
Yoke No.
Thick. Gauge No.
UV Light No.
Coil No.
Hardbanding: Present Plastic Coated:
CLEANING
Cat. 5
TBA*
Yes
Internal Qty
No
Pin
Box
Weight
Lbs/Ft
Tube OD
Threads
Nom Wall
Nom TJ OD
admin
10.04.2015
Modifier Name admin
Modification Date 10.04.2015
New Record - Detail
1400 bar ID Condition 2000 bar Special Hard Pollution
Wear Report Wear Report - Overview
Range
Grade Tube
Nom TJ ID
Min TJ OD
Repair - Hardbanding
Send to Trio
Repair - Machining
Send to NOS
INSPECTION RESULTS CLASS
TUBE TOOL JOINT
Premium
RECUT
SHOP REFACE
FIELD REFACE
PLASTIC COATING
HARDBANDING SER. NO. BENT PIN BOX RESTAMP
Joints
Joints
Total
Ok
OK
x1
Class2
Pin
Pin
Pin
Damaged
XT300 Rep.
x2
Scrap
Box
Box
Box
No Coat.
OTW12 Rep.
Number of Joints Inspected Number of Joints Require Shop Repair
(
Re-Cut with HB Damage)
Number of Hardbanding Repair
(Not Included In Recut Joints)
Number of Class2 & Scrap Number of Joints Ready For Use
Scrap per W.O. Wall Thickness Wear Preinvoice
Field Repair
Hours
Grinding Tongmarks and Slipcuts
Hours
Protectors Supplied By Euroincon
Qty.
Make Preinvoice
Relookup repair Required
Misc.
Number of Premium After Repair
Change Work Order
Comments
TAM Import
TAM - Make Field Copy NDT Level II Inspector
*TBA - To be applied
CERT. NO. NAME :
Odfjell Tag No List
Reports
MATERIAL Lot No.
Creator Date
New Record - Detail
Dope Applied
1400 bar External Qty 2000 bar Special Hard Pollution
Creator Name
We hereby confirm that the above material has been inspected in accordance with specified insp. proc., P.O. and Euroincon W.O.
Summary Report (Front page)
Field Copy
Print - Field Copy
Serial No TAM
Serial No TIM
Pages TAM Pages made
1
(Set to 1 if delete detail)
Restore
Inspection & Maintenance of Drill Pipe
The repair shop will issue their report after a repair. In this case a thread certificate (machining report) with the same reference to the unique equipment number, the standard used (Spec.), etc. for traceability.
Thread certificate
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Inspection & Maintenance of Drill Pipe
Preservation & Storage
Preservation & storage
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Inspection & Maintenance of Drill Pipe
Why use thread compounds? The drawing is a portion of a thread detail with API buttress threads, showing the compressible lubricant/pipe sealant in the gaps of the threaded connection.
PIN BOX G2 C G1 C
Thread compounds suitable for use in vertical and horizontal oil & gas wells using «API» oil country tubular goods tubing (OCTG), casing, and line pipe are designed to: • Provide lubricate • Plug the thread clearance • Prevent contamination of the natural environment • Prevent galling or scratches • Provide a coefficient of friction consistent with the connection requirements.
Used as an example, also valid for drill pipe threads
Inspection & Maintenance of Drill Pipe
Pipe storage Recommendations for pipe storage: • Do not put the pipe directly on the ground. The first layer of pipe should be no less than 0.3m above the ground. • The height of the pipe stack on a rack shall not exceed 2.5 m, and the pipe shall be secured with post to prevent rolling out. • When the pipe is laid in several rows, place 3 wooden blocks between each row so that the tool-joint elements do not touch each other. • Pipe shall be laid with boxes in the same directions • Rejected pipe or pipe going to be repaired, shall be laid on a separate rack and clearly identified
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Inspection & Maintenance of Drill Pipe
Preservation The use of protective compounds to protect equipment during storage and use.
Example of shoulder damage due to insufficient protector installation.
Picture shows dope where water has penetrated - gray color. May indicate that the protector has not tightened, or that temperature fluctuations may have caused the loosening.
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Inspection & Maintenance of Drill Pipe
The following are recommendations for the application and use of our thread compound on connections Upon opening the container, the product should
Contaminant residues, when mixed with
be stirred with either a dope brush or other
the thread compound during connections
suitable device to re-blend any oil separation or
engagement can substantially change the
settling of the component solids that may have
friction factor and galling resistance of the thread
occurred during shipment and storage.
compound. A small amount of moisture in most cases is unavoidable and will not affect compound
Never add any material such as diesel fuel,
performance.
kerosene, motor oil, etc. to improve the ease of application.
Note: These are general procedures not intended to replace the recommendations of the
All connections contact surfaces should be cleaned and free of storage or prior running compound, drilling fluids and any other contaminant residues prior to the applications of the compound.
connection manufactures.
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Inspection & Maintenance of Drill Pipe
Thread compounds
Pin
Example: Double Shouldered Connection
Primary Makeup Shoulder (for RSC’s)
Threads
Where are thread compounds used? Coat primary shoulder on interference designs Fill threads, only root to crest
Box
Too much compound interferes with connection make-up, too little may result in galling Secondary Seal
Coat secondary shoulder or seal area on applicable connection designs Ensure the connection is as free of drilling fluid as possible. Rinsing may be required
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Inspection & Maintenance of Drill Pipe
What quantity of threads compound is required on rotary shoulder connections?
Insufficient thread compound coverage for rotary
Proper Tread compound coverage for
shoulder connections
for rotary shoulder connections
Drill pipe protectors
Inspection & Maintenance of Drill Pipe
Preservation & Storage
Inspection standards
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Inspection & Maintenance of Drill Pipe
The most common inspection standards in use today, are:
API – American Petroleum Institute.
DS-1 – T.H. Hill Drill Stem Inspection.
NS-2 – Fearnley Procter North Sea Drill String Inspection Standard
Inspection & Maintenance of Drill Pipe
Preservation & Storage
Inspection companies
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Inspection & Maintenance of Drill Pipe
A general view on the necessary certifications for a thread inspector
Level 1 An individual certified to Level 1 has demonstrated competence to carry out NDT according to written instructions and under the supervision of Level 2 or Level 3 personnel.
Non Destructing Testing requires the inspectors to be certified in order to
Within the scope of the competence defined on the certificate, Level 1 personnel
perform certifications according
may be authorized by the employer to perform the following in accordance with
to standards.
NDT instructions;
EN 473/ISO 9712 (European standards)
a)
Set up NDT equipment
separates NDT inspectors into 3 levels.
b)
Perform the tests
c)
Record and classify the results of the tests according to written criteria
d)
Report the results
Level 1 certified personnel shall neither be responsible for the choice of test method or technique to be used, nor for the interpretation of test results.
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Inspection & Maintenance of Drill Pipe
Level 2 An individual certified to Level 2 has demonstrated competence to perform NDT according to NDT procedures. Within the scope of the competence defined on the certificate, the employer to may authorize Level 2 personnel:
a) Select the correct NDT technique for the actual test.
b) Define the limitations of application of the testing method
c)
d) Set up and verify equipment settings
e) Perform and supervise tests
f)
Translate NDT codes, standards, specifications, and procedures into NDT instructions adapted to the actual working conditions
Interpret and evaluate results according to applicable standards, codes, specifications or procedures
g) Carry out and supervise all tasks at or below Level 2
h) Provide guidance for personnel at or below Level 2
i) Report the results of NDT.
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Inspection & Maintenance of Drill Pipe
Level 3 An individual certified to Level 3 has demonstrated competence to perform and direct NDT operations for which he is certified. Level 3 personnel have demonstrated:
a) The competence to evaluate and interpret results in terms of existing
standards, codes, and specifications
b) Sufficient practical knowledge of applicable materials, fabrication,
process, and product technology to select NDT methods, establish NDT
techniques, and assist in establishing acceptance criteria where none or
are otherwise available
A general familiarity with other NDT methods
c)
Within the scope of the competence defined on the certificate, Level 3 personnel may be authorized to:
a) Assume full responsibility for a test facility or examination center
and staff
b) Establish, review for editorial and technical correctness, and validate NDT
instructions and procedures
c)
Interpret standards, codes, specifications, and procedures
d) Designate the particular test methods, procedures, and NDT
instructions required
e) Carry out and supervise all tasks at all levels
f)
Provide guidance for NDT personnel at all levels
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Inspection & Maintenance of Drill Pipe
Approval / Certification To be performed by an accredited certification business.
Requirements for practice and introduction to NDT method before courses / issuance of certificate: Method
Level 1
Level 2
Level 3
MT
1 mnd.
3 mnd.
12 mnd.
PT
1 mnd.
3 mnd.
12 mnd.
UT
3 mnd.
9 mnd.
18 mnd.
RT
3 mnd.
9 mnd.
18 mnd.
ET
3 mnd.
9 mnd.
18 mnd.
VT
1 mnd.
3 mnd.
12 mnd.
Inspection & Maintenance of Drill Pipe
Documentation Companies have a responsibility to keep and annually update their certificates to the inspectors. Each year the responsible level 3 perform a competency assessment of the individual inspector. Near- and color vision are verified, before the certificate are approved for another 12 months. After 5 years, an application must be submitted to the certification body, to renew the certificate for another five years. After 10 years you have to do a complete course with tests.
Reporting Responsible level 3 shall report annually to the certification body on the status of the enterprise for the year that has passed. • Are all certificates updated? • Is it registered complaints in the past 12 months? • Are there major changes in the organization over the last 12 months?
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Inspection & Maintenance of Drill Pipe
Odfjell Well Services Hammaren 19 P.O.Box 152 N0-4098 Tananger Norway Tlf: +47 51 64 84 00 Fax: +47 51 64 71 81
[email protected] www.odfjellwellservices.com
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