API Spec 6a Material

Purchasing Guide for Wellhead & Christmas Tree Equipment

With Reference to API 6A, 19th Edition, Including Changes in NACE MR0175, ISO 15156, Latest Edition.

OU R C O M

P A N Y Stream-Flo

o

manu

wned

Industries Ltd

and

operated

. is a privately

Ca

nadian

facturer of

wellhead and christmas tree equipment, gate valves, ESD’s and check valves. Founded in

1962, the company has grown to be one of the largest manufacturers of its kind in Canada and is continually expanding its export activities. Our commitment to core values of unceasingly improving and investing in technology and striving for high standards in our people has made Stream-Flo the successful company it is today. With this success, we are better equipped to provide excellent and consistent customer service. This customer service translates to improved quality, reduced cost of the finished product, and shorter delivery schedules. Further improvements are achieved through close partnering with material suppliers and subcontractors.

Table of Contents Thoughts from the Corporate Quality Manager/Senior Metallurgist . . . . . . . . . . . iii API Specification 6A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Abbreviated Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 API 6A Applicable Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Significant Differences Between API 17 and 19 Editions . . . . . . . . . . . . . . . . . . 3 Quality Requirements: Bull Plug, Valve Removal Plug and Back Pressure Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Plan-Do-Check-Act . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Continual Improvement of the Quality Management System . . . . . . . . . . . . . . . . 5 Standard Material Applications: Bodies, Bonnets and End and Outlet Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Standard Material Property Requirements: Bodies, Bonnets and End and Outlet Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Charpy V Notch Impact Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Temperature Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pressure Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . API 6A Annex O: Material Class ZZ . . . . . . . . . . . . . . . . . . . . . . . More NACE Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . .

. . . . .

. . . . .

. . . . .

. . . . .

. . . . .

. . . . .

. . . . .

. . . . .

7 7 8 8 8

Product Specification Levels (PSLs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 PSL Decision Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 API Marking Requirements and Locations . . . . . . . . . . . . . . . . . . . Quality Control Requirements: Bodies, Bonnets, End and Outlet Connections, and Hub End Connectors . . . . . . . . . . . . . . . . . . . . . Thread Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Quality Control Requirements for Welding . . . . . . . . . . . . . . . . . . .

. . . . . . . . 10 . . . . . . . . 11 . . . . . . . . 11 . . . . . . . . 12

Relative Corrosivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Relative Corrosiveness of Retained Fluids . . . . . . . . . . . . . . . . . . . . Factors Affecting Behavior in H2S Containing Environments . . . . . . . . . Severity of Sour Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . .

. . . .

. . . .

. . . .

. . . .

. . . .

. . . .

13 13 13 14

The API Monogram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Performance Verification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 API Order Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Guiding Principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

i

Canadian Head Office and Manufacturing Facility, Edmonton, Alberta, Canada

United States Wellhead and Check Valve Business Units, Houston, Texas, USA

When coupled with Stream-Flo processes, API provisions, and applicable customer requirements, this booklet is intended to provide a common fundamental approach to quality management for the petroleum, petrochemical and natural gas industry.

Message from the Corporate Quality Manager/Senior Metallurgist

First of all, at Stream-Flo, we have a strong desire to service the customer. We find out our customer’s needs and get it delivered in the best condition as quickly as possible. Second, when I look at our corporate manufacturing operations, I see the commitment toward quality. We have a strong passion to make sure the customer is always satisfied, recognizing the value-added advantage of dealing with Stream-Flo Industries Ltd. Third, we monogram all our products, thereby reinforcing our conformance to API 6A and 6D, as applicable. Stream-Flo has stable operation, quality, marketing, and engineering organizations. With three metallurgists on staff, we provide comprehensive expertise to our customers: material selection, heat treatment, corrosion, welding, and solving metallurgical and welding problems.

“There are times when I ask myself, What makes us a better choice than the other guy?

”

As Corporate Quality Manager and Senior Metallurgist over the past 25 years, I have seen the changes that have taken place within Stream-Flo’s systems and processes. Operations and management are committed to maturing and comprehensive quality, engineering, and materials program with documented procedures complying to API Q1 and ISO 9001.

Martin Ishkanian

iii

API Specification 6A API Specification 6A (ISO 10423) is the recognized industry standard for wellhead and christmas tree equipment that was formulated to provide for the availability of safe, dimensionally and functionally interchangeable wellhead and christmas tree equipment. This specification includes detailed requirements for the manufacture of tubular suspension equipment, valves, and fittings used at the location of oil and gas wells to contain and control pressure and fluid flows.

Specification 6A also serves as the reference source for the design of flanged end and outlet connections for use at 2,000 to 20,000 psi maximum rated working pressures and a family of gate valves for use over these same pressure ranges. Since API Specification 18th Edition was withdrawn, this booklet covers the 19th Edition with references to the 17th Edition.

Abbreviated Terms AQL CRA DAC ER FEA HAZ HBW HIP HRB HRC NDE NPT OEC OEM

Acceptable Quality Level Corrosion Resistant Alloy Distance Amplitude Curve Equivalent Round Finite Element Analysis Heat Affected Zone Brinell Hardness Hot Isostatic Pressing Rockwell Hardness Scale B Rockwell Hardness Scale C Nondestructive Examination National Pipe Thread Other End Connection Original Equipment Manufacturer

PQR PR PSL QTC r.m.s. RL Rm ROE SSV TC UNS USV WPQ WPS

1

Procedure Qualification Record Performance Requirement Product Specification Level Qualification Test Coupon Root Mean Square Repair/Remanufacture Level Ultimate Tensile Strength Radius of Exposure Surface Safety Valve Test Coupon Unified Numbering System Underwater Safety Valve Welder Performance Qualification Welding Procedure Specification

API 6A Applicable Equipment API Specification 6A covers wellhead and christmas tree equipment as follows: API 6A Applicable Equipment Wellhead Equipment

Connectors and Fittings

casing head housings casing head spools

cross-over connectors tubing head adaptors

tubing head spools

Casing and Tubing Hangers mandrel hangers slip hangers

Valves and Chokes

Loose Connectors

1

Other Equipment

single valves multiple valves

weld neck connections blind connectors

actuators

top connectors

actuated valves

threaded connectors

presure boundary penetrations

cross-over spools

tees and crosses

valves prepared for actuators

adaptor and spacer connections

ring gaskets

multi-stage head housings and spools

fluid sampling devices

check valves

bull plugs

running and testing tools (in Annex H)

adaptor and spacer spools

chokes

valves removal plugs

wear bushings (in Annex H)

hubs

surface and underwater safety valves and actuators back-pressure valves

Flanged, threaded, other end connectors (OEC) and welded. Note: This international standard defines service conditions in terms of pressure, temperature and material class for the well-bore constituents and operating conditions. 1

Significant Differences Between API 17 and 19 Editions Due to the significant differences between current and previous API standards, much equipment commonly used in the field may have to be replaced to comply with new API requirements. Valve Removal Plugs and Threads Added Valve removal plugs and threads were previously the responsibility of the manufacturer. The specified threads for ≤10,000 psi are Charpy V tubing threads from the 1946 edition of API 5B. The LP plug previously used will engage an outlet with either LP or Charpy V threads. The new Charpy V plug will not fit into an outlet with LP threads. The specified connections for 15,000 and 20,000 psi is a stub ACME with a metal-to-metal seal. Top Connection Assemblies Shall Be Equipped with a Bleeder Plug Bleeder plugs must now be shipped with bottom hole test adapters. A needle valve which is normally shipped with BHTA will meet this requirement. Recommended Design for Top Connectors Added An optional annex has been added that shows dimensional information for bottom hole test adapters. NACE MR0175/ISO 15156-1 Many necessary changes were made to API 6A to reflect the new NACE standard. One significant change concerning wellhead equipment is the limit of 0.5 psi partial pressure of H2S for 17-4 PH. Temperature Class N Added As NACE now restricts a maximum temperature rating of 140° F, the temperature Class N -50° F to 140° F (-46° C to 60° C) was added to accommodate austenitic stainless steels (e.g. 316). Partial Pressure Stamping for Sour Service Added The maximum allowable partial pressure of H2S will be stamped immediately after the material class. Where no limit is defined, NL will be stamped.

New PSL-3G Added A new PSL with gas testing required has been added with the designation PSL-3G. Running Tools, Test Tools and Wear Bushings Added Running tools, test tools and wear bushings may now be monogrammed. There are no dimensions specified. Design and material requirements are identified. Repair and Remanufacture Annex Added Annex Q has been added to API 6A. This annex defines the requirements for repair and remanufacture of user/purchaser-owned equipment originally manufactured in accordance with API 6A. Repaired or remanufactured equipment is not eligible for licensing under the API Monogram Program. Back Pressure Valves Added Back pressure valves may now be monogrammed. There are no dimensions specified; however, design and performance requirements are identified. Bull Plugs Added Bull plugs are now included and may now be monogrammed. Materials and dimensions are specified. Material Class ZZ Added Material Class ZZ allows materials outside of NACE MR0175 limits for sour service applications. Test Pressure Hydrostatic Body Test Pressure.

Refer

to

API Table 19,

Quality Requirements Bull Plug, Valve Removal Plug, and Back Pressure Valve Material (bull plugs) 60K psi 1 Hardness testing is not Material (valve removal plugs 60K psi 2,000 - 10,000 required for those materials and back pressure valves) 75K psi 15,000 - 20,000 that have no hardness restrictions specified by Tensile Testing Preheat NACE MR0175 or are not Impact Testing Preheat heat treated to obtain a Hardness Test 1 Sampling minimum specified strength NACE MR0175 2 100% level. Dimensional Sampling 2 100% valve sealing Traceability Job Lot mechanism for back pressure valves. Chemical Analysis Preheat 3 100% assembly for Visual Examination Sampling back pressure valves. Hydrostatic Test 3 -

API Table 19 Hydrostatic Body Test Pressure End and Outlet Connections Working Pressure Rating MPa (psi) 13.8 (2,000) 20.7 (3,000) 34.5 (5,000) 69.0 (10,000) 103.5 (15,000) 138.0 (20,000)

Nominal Flange Size mm (in) 346 (135/8) and smaller MPa (psi) 27.6 (4,000) 41.5 (6,000) 51.7 (7,500) 103.5 (15,000) 155.0 (22,500) 207.0 (30,000)

425 (163/4) and larger MPa (psi) 20.7 (3,000) 31.0 (4,500) 51.7 (7,500) 103.5 (15,000) 155.0 (22,500) -

Line Pipe and Tubing Threads MPa (psi) 27.6 (4,000) 41.5 (6,000) 51.7 (7,500) 103.5 (15,000)

Casing Threads mm (in) 114.3 - 273.1 298.5 - 338.7 406.5 - 508.0 (41/2 - 103/4) (113/4 - 133/8) (16 - 22) MPa (psi) MPa (psi) MPa (psi) 27.6 27.6 15.5 (4,000) (4,000) (2,250) 41.5 31.0 (6,000) (4,500) 51.7 (7,500) -

-

-

-

-

-

-

-

-

-

-

4

Plan-Do-Check-Act The model of a process-based quality management system illustrates that the customers play a significant role in defining requirements as inputs. Monitoring of customer satisfaction requires the evaluations of information relating to customer perception as to whether the organization has met the customer requirements. The Plan-Do-Check-Act (PDCA) can be applied to all processes: Plan

Establish the objectives and processes necessary to deliver results in accordance with customer requirements and the organization’s policies. Do Implement the processes. Check Monitor and measure the processes and product against policies, objectives and requirements for the product and report the results. Act Take actions to continually improve the process performance. Continual Improvement of the Quality Management System Management Responsibility

Customers’ Requirements

Resource Management

input

Measurement, Analysis and Improvement

Product Realization

Product

value-adding activities information flow

output

Customers’ Satisfaction

5

End Connect ion Integral Connection Loose

Standard Material Applications Bodies, Bonnets, andRatings End andMPa Outlet Pressure (psi)Connections 13.8 20.7 34.5 69.0 103.5 138.0 Part (2,000) (3,000) (5,000) (10,000) (15,000) (20,000) 36K, 45K, 36K, 45K, 36K, 45K, 36K, 45K, 45K, 60K, 45K, 60K, Body a, 60K, 75K, NSb 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS 75K, NS 75K, NS Bonnet flange 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS threaded 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS c c c c c c other c welding 45K 45K 45K 60K, 75K, NS 75K, NS 75K, NS neck blind 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS 75K, NS 75K, NS threaded 60K, 75K, NS 60K, 75K, NS 60K, 75K, NS NA NA NA c c c c c c c other

a

b c

If end connections are of the material designation indicated, welding is in accordance with Clause 6 and design is in accordance with Clause 4. NS indicates nonstandard materials. As specified by manufacturer. Standard Material Property Requirements Bodies, Bonnets, and End and Outlet Connections Material Designation 36K 45K 60K 75K

0.2% Yield Strength min MPa (psi) 248 (36,000) 310 (45,000) 414 (60,000) 517 (75,000)

Tensile Strength min MPa (psi) 483 (70,000) 483 (70,000) 586 (85,000) 655 (95,000)

Elongation in 50 mm (2 in) min % 21 19 18 17

Reduction in Area min % no requirements 32 35 35

Charpy V Notch Impact Requirements (10 mm x 10 mm) Minimum Average Impact Value Temperature Traverse Direction J (ft lb) Temp Class Test Temp °C (°F) PSL 1 PSL 2 PSL 3 and PSL 4 K -60 (-75) 20 (15) 20 (15) 20 (15) L N P R S T U V

-46 (-50) -46 (-50) -29 (-20) -18 (0) -18 (0) -18 (0) -18 (0) -18 (0)

20 (15) 20 (15) 6

20 (15) 20 (15) 20 (15) -

20 (15) 20 (15) 20 (15) 20 (15) 20 (15) 20 (15) 20 (15) 20 (15)

Temperature Ratings Temperature Classification K L N

(min) -60 -46 -46

P R S T U V

°C

Operating Range (max) (min) 82 -75 82 -50 60 -50

-29 82 room temperature -18 60 -18 82 -18 121 2 121 -18 180 -18 345

°F

(max) 180 180 140

-20 180 room temperature 0 140 0 180 0 250 35 250 0 350 0 650

X1 Y1 1 Reference Annex G for details of design and temperature rating of equipment for use at elevated temperatures. Note: Annex G is not intended as a material selection guide for high temperature use. Some alloys are embrittled after repeated or prolonged exposure to elevated temperatures. Care should be used in selection of alloys for these ratings. If plated or coated materials are used at temperatures greater than 180° C (350° F), cracking potential can be increased.

Pressure Ratings API Pressure Rating in MPa 13.8 20.7 34.5 69.0 103.5 138.0 Pressure Rating for Class K to U MPa (psi) 13.8 (2,000) 20.7 (3,000) 34.5 (5,000)

API Pressure Rating in PSI 2,000 3,000 5,000 10,000 15,000 20,000 De-rated Pressure Class X MPa (psi) Class Y MPa (psi) 13.1 (1,905) 9.9 (1,430) 19.7 (2,860) 14.8 (2,145) 32.8 (4,765) 24.7 (3,575) 7

Material Classes Material Class AA - General Service BB - General Service CC - General Service DD - Sour Service a EE - Sour Service a FF - Sour Service a HH - Sour Service a ZZ - Sour Service

Minimum Material Requirements Body, Bonnet, End & Pressure-Controlling Parts, Outlet Connections Stems & Mandrel Hangers Carbon or Low-alloy Steel Carbon or Low-alloy Steel Carbon or Low-alloy Steel Stainless Steel Stainless Steel Stainless Steel b Carbon or Low-alloy Steel Carbon or Low-alloy Steel b Carbon or Low alloy Steel b Stainless Steel b Stainless Steel Stainless Steel b CRAs bcd CRAs bcd User Defined User Defined

As defined by NACE MR0175/ISO 15156 in compliance with NACE MR0175/ISO 15156. In compliance with NACE MR0175/ISO 15156. c CRA required on retained fluid wetted surfaces only. CRA cladding of low alloy or stainless steel is permitted. d CRA as defined in Clause 3 of this International Standard. NACE MR0175/ISO 15156 definition of CRA does not apply. a b

API 6A Annex O: Material Class ZZ NACE MR0175/ISO 15156 includes provisions for the qualification of materials for a specific sour service application which is outside the parameters defined in that standard by means of testing or documented field history. This can include MR0175/ISO 15156 or the use of materials not addressed in MR0175/ISO 15156. For such sour service applications, equipment may be described and marked as Material Class ZZ. It is the responsibility of the purchaser to evaluate and determine the applicability of the documented data for the intended application. For material Class ZZ, the manufacturer shall meet material specifications supplied or approved by the purchaser and shall maintain traceable records to document the materials of construction, regardless of PSL.

More NACE Information Material Classes DD, EE, FF and HH require compliance to NACE MR0175 (ISO 15156) and responsibility for the choice rests with the purchaser. Examples of Designations Class FF-1.5 means: a) material class FF b) rated at 1.5 psia H2S maximum allowable partial pressure 8

Class NL means: a) where no H2S limit is defined by NACE, NL shall be used for marking (i.e. DD-NL).

9

Product Specification Levels (PSL) API Specification 6A (ISO 10423) recommends product specification levels (PSLs) for equipment with quality control requirements for various service conditions. PSLs apply to primary equipment: • • • •

tubing heads tubing hangers, hanger couplings tubing head adapters lower master valves

All other wellhead parts are classified as secondary. The PSL for secondary equipment may be the same or less than the PSL for primary equipment.

PSL Decision Tree Recommended minimum PSL for primary parts of wellhead and christmas tree equipment.

start rated working pressure

103.5 MPa ≥ 15,000 psi) (

34.5 MPa (5,000 psi)

≤34.5 MPa (5,000 psi)

3G 3 gas well?

no

yes

3G

3 2

gas well?

yes

rated working pressure

≤34.5 MPa (5,000 psi)

no rated working pressure rated working pressure

>34.5 MPa ( 5,000 psi)

≤34.5 MPa (5,000 psi)

>34.5 MPa (5,000 psi)

>34.5 MPa (5,000 psi) ≤34.5 MPa (5,000 psi)

gas well?

yes

3 2 2 1 3

no 2 1

9

API Marking Requirements and Locations Location Marking

ISO 10423 temperature class or rating (4.2.2)

material class (4.2.3)

Wellhead Equipment

Connectors and Fittings

Casting and Tubing Hangers

Loose Connectors

Valves and Chokes

Actuators

nameplate and/or body

nameplate and/or body

nameplate and/or body

OD of connector

nameplate and/or body

nameplate and/or body

nameplate and/or body

nameplate and/or body (actuators containing retained fluid)

nameplate and/or body

nameplate and/or body (actuators containing retained fluid)

nameplate and/or body

nameplate and/or body

nameplate and/or body

nameplate and/or body

nameplate and/or body

nameplate and/or body

OD of connector

OD of connector

product specification level (1.4)

nameplate and/or body

nameplate and/or body

nameplate and/or body

OD of connector

nameplate and/or body

nameplate and/or body (actuators containing retained fluid)

performance requirement level (4.1)

nameplate and/or body

-

nameplate and/or body

OD of connector

nameplate and/or body

nameplate and/or body

nominal size (bore if required)

nameplate or body, and connector OD

nameplate or body, and connector OD

nameplate and/or body

OD of connector

nameplate and/or body

nameplate and/or body

thread size (threaded products only)

nameplate or body, and/or near each thread

nameplate or body, and/or near each thread

nameplate and/or near each connector

OD of connector

nameplate or body, and/or near each thread

-

end and outlet connector size

nameplate or body, and each connector OD

nameplate or body, and each connector OD

-

OD of connector

nameplate and/or body

-

rated working pressure (4.2.1)

nameplate or body, and each connector OD

nameplate or body, and each connector OD

-

OD of connector

ring gasket type and number

near each connector

near each connector

-

OD of connector

near each connector

-

date of manufacture

nameplate and/or body

nameplate and/or body

nameplate and/or body

OD of connector

nameplate and/or body

nameplate and/or body

manufacturer’s name or mark

nameplate and/or body

nameplate and/or body

nameplate and/or body

OD of connector

nameplate and/or body

nameplate and/or body

serial number (if applicable)

nameplate and/or body

nameplate and/or body

nameplate and/or body

OD of connector

nameplate and/or body

nameplate and/or body

hardness test values (if applicable)

adjacent to test location

adjacent to test location

adjacent to test location

adjacent to test location

adjacent to test location

adjacent to test location

10

nameplate or body, and each connector OD

-

Quality Control Requirements Bodies, Bonnets, End and Outlet Connections, and Hub End Connectors Parameter Tensile Testing Impact Testing Hardness Testing NACE MR0175 Dimensional Verification Traceability Chemical Analysis Visual Examination Surface NDE

PSL 1 7.4.2.1.1 7.4.2.1.2 7.4.2.1.3 7.4.1.5 7.4.2.1.4 7.4.2.1.5 -

Weld NDE General Examination Visual NDE Surface Repair Welds NDE Volumetric Hardness Testing Serialization Volumetric NDE

7.4.2.1.6 -

7.4.2.1.6 7.4.2.2.11 7.4.2.2.12

-

7.4.2.2.13 7.4.2.2.14 -

7.4.2.1.6 7.4.2.3.10 7.4.2.2.12 7.4.2.3.11 7.4.2.2.13 7.4.2.3.12 7.4.2.3.13

-

-

7.4.2.3.14 7.4.2.3.15

Thread Markings The thread type marking in accordance with ISO 11960 shall be as follows:

11

Subclause Reference PSL 2 PSL 3/3G 7.4.2.2.1 7.4.2.2.1 7.4.2.2.2 7.4.2.3.2 7.4.2.2.3 7.4.2.3.3 7.4.1.5 7.4.1.5 7.4.2.1.4 7.4.2.3.4 7.4.2.2.5 7.4.2.3.5 7.4.2.2.6 7.4.2.2.6 7.4.2.1.5 7.4.2.2.7 7.4.2.2.8 7.4.2.3.8 7.4.2.2.9

STC LC BC XL LP NU EU

PSL 4 7.4.2.2.1 7.4.2.3.2 7.4.2.3.3 7.4.1.5 7.4.2.3.4 7.4.2.3.5 7.4.2.2.6 7.4.2.3.8

No welding permitted except for weld overlays (see 7.4.2.4.9) 7.4.2.3.14 7.4.2.4.11

Casing: short thread Casing: long thread Casing: buttress Casing: extreme Line Line pipe Tubing: non-upset Tubing: external upset

Weld Type Pressure containing

Non-pressure containing

Repair Weld metal overlay (ring grooves, stems, valve-bore sealing mechanisms and choke trim) Weld metal corrosive resistant alloy overlay (bodies, bonnets and end and outlet connections)

Quality Control Requirements for Welding Stages PSL 1 PSL 2 PSL 3/3G Preparation a a, b and a, b, (c or d), Completion and e (c or d)

Preparation no welding permitted

Preparation

-

-

a

Completion Preparation

-

Completion

-

Preparation

-

a h a, b, and (f or g) -

a and e h a, b, e and (f or g) b

Completion

-

b

b

b

Preparation

a

a

a

a

Completion

a,b

a,b

a, b, i

a, b, i

no welding permitted no welding permitted b

a Visual examination. b Penetrant testing inspection for non-ferromagnetic materials and magnetic particle testing for ferromagnetic material. c Radiation (radiography or imaging) examination. d Ultrasonic examination. e Hardness test (weld). f Ultrasonic examination only if weld is greater than 25% of wall thickness or 25 mm (1 in), whichever is less. g Radiation (radiography or imaging) examination only if weld is greater than 25% or wall thickness for PSL 2 or 20% of wall thickness for PSL 3, or 25 mm (1 in), whichever is less. h Penetrant or magnetic particle as applicable for material defects only. i Measurement of overlay thickness, testing of bond integrity and volumetric examination shall be according to the manufacturer’s specifications. If the overlay is considered part of the manufacturer’s design criteria or of the design criteria of API 6A, volumetric examinations shall be in accordance with the methods and acceptance criteria of 7.4.2.3.15. Note: preparation = surface preparation, joint preparation, fit up and preheat completion = after all welding, post-weld heat treat and

12

Relative Corrosivity The minimum partial pressure of carbon dioxide required to initiate corrosion and the relative effect of increasing partial pressures on the corrosion rate are strongly influenced by other environmental factors: a) b) c) d) e) f) g)

temperature H2S level pH chloride ion concentration sand production water production and composition types and relative amounts of produced hydrocarbons

Finally, the purchaser should consider future service of the well when selecting a material class. This should not be limited to anticipated changes in the acid gas partial pressures for production or increased water production with or without increased chloride content, but also should include consideration of operations such as acidification or other well treatments. Relative Corrosiveness of Retained Fluids as Indicated by CO2 Partial Pressure Retained Fluids general service general service general service sour service sour service sour service

Retained Fluids noncorrosive slightly corrosive moderately to highly corrosive noncorrosive slightly corrosive moderately to highly corrosive

Retained Fluids Mpa 30)