Purchasing Guide for Wellhead & Christmas Tree Equipment

Transcription

1 Purchasing Guide for Wellhead & Christmas Tree Equipment WORLDWIDE EXPERTISE GLOBAL STRENGTH With Reference to API 6A, 20th Edition, Including Changes in NACE MR0175/ISO 15156, 2009 Edition.

2 When coupled with StreamFlo processes, API provisions and customer applications, this booklet is intended to provide insight into API requirements for equipment and quality management systems, and to provide a fundamental approach to the purchasing of equipment for the petroleum, petrochemical and natural gas industries.

3 Table of Contents API Specification 6A Abbreviated Terms (Some Examples) API 6A Applicable Equipment Significant Differences Between API 19th and 20th Editions Hydrostatic Body Test Pressure PlanDoCheckAct Continual Improvement of the Quality Management System Standard Material Applications: Bodies, Bonnets and End and Outlet Connections Standard Material Property Requirements: Bodies, Bonnets and End and Outlet Connections Charpy V Notch Impact Requirements Temperature Ratings Pressure Ratings Material Classes API 6A Annex O: Material Class ZZ More NACE Information Product Specification Levels (PSL) PSL Decision Tree 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 Bodies, Bonnets, and End and Outlet Connectors Relative Corrosivity Relative Corrosiveness of Retained Fluids as Indicated by CO 2 Partial Pressure Factors Affecting Behavior in H 2 S Containing Environments Severity of Sour Environment The API Monogram Performance Validation Criteria for Ordering, 20th Edition API Order Form i

4 API Specification 6A API Specification 6A (ISO 10423) is the recognized industry standard for wellhead and christmas tree equipment. It was formulated to provide for the availability of safe, dimensionally and functionally interchangeable wellhead and christmas tree equipment. The 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. This booklet covers the 20th Edition with references to the 19th Edition. Abbreviated Terms (Some Examples) AQL Acceptable Quality Level PR Performance Requirement CRA Corrosion Resistant Alloy PSL Product Specification Level DAC Distance Amplitude Curve QTC Qualification Test Coupon ER Equivalent Round RMS Root Mean Square FEA Finite Element Analysis RL Repair/Remanufacture Level HAZ Heat Affected Zone R p Yield Strength HBW Brinell Hardness R m Ultimate Tensile Strength HIP Hot Isostatic Pressing ROE Radius of Exposure HRB Rockwell Hardness Scale B SSV Surface Safety Valve HRC Rockwell Hardness Scale C TC Test Coupon NDE Nondestructive Examination UNS Unified Numbering System NPT National Pipe Thread USV Underwater Safety Valve OEC Other End Connection WPQ Welder Performance Qualification OEM Original Equipment Manufacturer WPS Welding Procedure Specification PQR Procedure Qualification Record PPM Parts Per Million 1

5 API 6A Applicable Equipment API Specification 6A covers wellhead and christmas tree equipment as follows: Wellhead Equipment Casing head housing Casing head spools Tubing head spools Crossover spools Multistage head housing and spools Connectors & Fittings Crossover s Tubing head adaptors Top s Tees and crosses Fluid sampling devices Adaptor and spacer spools Casing & Tubing Hangers Mandrel hangers Slip hangers Other Equipment Actuators Clamp hubs Pressure boundary penetrations Ring gaskets Running and testing tools 2 Wear bushings 2 Valves & Chokes Single valves Multiple valves Actuated valves Valves prepared for actuators Check valves Chokes Surface and underwater safety valves and actuators Backpressure valves Loose Connectors 1 Weld neck connections Blind s Threaded s Adaptor and spacer connections Bullplugs Valves removal plugs Note: 1 Flanged, threaded, other end s (OEC) and welded. 2 See API 6A 20th Edition, Annex H API 6A defines service conditions in terms of pressure, temperature and material class for the wellbore constituents and operating conditions. 2

6 Significant Differences Between API 19th and 20th Editions Unlike the changes that were made between the 17th and 19th Editions, the changes in the 20th Edition were relatively minor. Pressure Recording Devices A distinction has been made between pressure measuring and pressure recording devices. A pressure recording device is not considered to be a pressure measuring device unless it is being utilized as both a measuring and recording device. Removal of Material Class R API has removed the Material Class R temperature rating. This temperature rating was used for room temperature applications. Castings no longer permitted for PSL4 Material for PSL4 equipment must be manufactured from wrought products. Visual Examination Personnel Added requirements for personnel performing visual examination for acceptance to pass eye exam. API Table 31 Quality Control Requirements for Welding This is one of the biggest changes to the API 6A Specification. The table controlling the quality control requirements for welding was reorganized and restructured to categorize welding differently. Welding is now grouped into Pressurecontaining, Nonpressurecontaining, Pressurecontaining repairs, Weld metal overlay partial, and Weld metal overlay full overlay. This, along with the changes to the inspection requirements, are a fundamental change in how welding is controlled and monitored. Design Validation Terminology changed from Design Verification to Design Validation. Hard facing and Overlay of ValveBore Sealing Mechanisms The property control requirements for hard facing and the weld overlay of valvebore sealing mechanisms, choke trim and valve stems have been relaxed. Working Pressure Rating MPa (psi) 13.8 (2,000) 20.7 (3,000) 34.5 (5,000) 69.0 (10,000) (15,000) (20,000) Nominal Flange Size mm (in) 346 (13 5 /8) and smaller MPa (psi) 27.6 (4,000) 41.5 (6,000) 51.7 (7,500) (15,000) (22,500) (30,000) 425 (16 3 /4) and larger MPa (psi) 20.7 (3,000) 31.0 (4,500) 51.7 (7,500) (15,000) (22,500) Hydrostatic Body Test Pressure End and Outlet Connections Line Pipe and Tubing Threads MPa (psi) 27.6 (4,000) 41.5 (6,000) 51.7 (7,500) (15,000) (4 1 / /4) MPa (psi) 27.6 (4,000) 41.5 (6,000) 51.7 (7,500) Casing Threads mm (in) (11 3 / /8) MPa (psi) 27.6 (4,000) 31.0 (4,500) (16 20) MPa (psi) 15.5 (2,250) 3

7 PlanDoCheckAct The model of a processbased quality management system illustrates that our customers play a significant role in defining requirements as inputs. Monitoring of customer satisfaction requires the evaluation of information relating to customer perception as to whether the organization has met customer requirements. The PlanDoCheckAct (PDCA) can be applied to all processes: Plan Do Check Act Establish the objectives and processes necessary to deliver results in accordance with customer requirements and the organization s policies. Implement the processes. Monitor and measure the processes and product against policies, objectives and requirements for the product and report the results. Take actions to continually improve process performance. Continual Improvement of the Quality Management System Management Responsibility Customers Requirements Resource Management Measurement, Analysis and Improvement Customers Satisfaction input Product Realization Product output information flow 4

8 API 6A, Table 5 Integral End Connection Loose Connectors Part Body a, Bonnet 13.8 (2,000) Standard Material Applications Bodies, Bonnets, and End and Outlet Connections Pressure Ratings MPa (psi) 20.7 (3,000) 36K, 45K, 36K, 45K, 60K, 75K, NS b 60K, 75K, NS 34.5 (5,000) 36K, 45K, 60K, 75K, NS 69.0 (10,000) 36K, 45K, 60K, 75K, NS (15,000) 45K, 60K, 75K, NS (20,000) 60K, 75K, NS flange 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 other c c c c c c c welding neck 45K 45K 45K 60K, 75K, NS 75K, NS 75K, NS 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 other c c c c c c c a If end connections are of the material designation indicated, welding is in accordance with Clause 6 b c and design is in accordance with Clause 4. NS indicates nonstandard materials. As specified by manufacturer. 5

9 API 6A, Table 6 Material Designation Standard Material Property Requirements Bodies, Bonnets, and End and Outlet Connections 0.2% Yield Strength min MPa (psi) Tensile Strength min MPa (psi) Elongation in 50 mm (2 in) min % Reduction in Area min % 36K 248 (36,000) 483 (70,000) 21 no requirements 45K 310 (45,000) 483 (70,000) K 414 (60,000) 586 (85,000) K 517 (75,000) 655 (95,000) API 6A, Table 7 Temperature Charpy V Notch Impact Requirements (10 mm x 10 mm) Minimum Average Impact Value 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 46 (50) 20 (15) 20 (15) 20 (15) N 46 (50) 20 (15) 20 (15) 20 (15) P 29 (20) 20 (15) 20 (15) S 18 (0) 20 (15) T 18 (0) 20 (15) U 18 (0) 20 (15) V 18 (0) 20 (15) V 18 (0) 20 (15) 6

10 Temperature Ratings API 6A, Table 2 Temperature Classification Operating Range (min) C (max) (min) F (max) K L N P S T U V X Y 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 API Pressure Rating in PSI , , , , , ,000 Pressure Rating for Class K to U Derated Pressure MPa (psi) Class X MPa (psi) Class Y MPa (psi) 13.8 (2,000) 13.1 (1,905) 9.9 (1,430) 20.7 (3,000) 19.7 (2,860) 14.8 (2,145) 34.5 (5,000) 32.8 (4,765) 24.7 (3,575) 7

11 Material Classes Material Class Body, Bonnet, End & Outlet Connections Minimum Material Requirements PressureControlling Parts, Stems & Mandrel Hangers AA General Service Carbon or Lowalloy Steel Carbon or Lowalloy Steel BB General Service Carbon or Lowalloy Steel Stainless Steel CC General Service Stainless Steel Stainless Steel DD Sour Service a Carbon or Lowalloy Steel b Carbon or Lowalloy Steel b EE Sour Service a Carbon or Low alloy Steel b Stainless Steel b FF Sour Service a Stainless Steel Stainless Steel b HH Sour Service a CRAs bcd CRAs bcd ZZ Sour Service User Defined User Defined a As defined by NACE MR0175/ISO b In compliance with NACE MR0175/ISO 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 API 6A 20th Edition. NACE MR0175/ISO definition of CRA does not apply. API 6A Annex O: Material Class ZZ NACE MR0175/ISO includes provisions for the qualification of materials for a specific sour service application that is outside the parameters defined in that standard by means of testing or documented field history. This can include NACE MR0175/ISO or the use of materials not addressed in NACE MR0175/ISO 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 and responsibility for the choice rests with the purchaser. Examples of Designations Class FF1.5 means: a) Material class FF b) Rated at 1.5 psia H 2 S maximum allowable partial pressure Class NL means: a) Where no H 2 S limit is defined by NACE, NL shall be used for marking (i.e. DDNL). 8

12 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 MPa (15,000 psi) High H 2 S concentration? yes PSL 3G <103.5 MPa (15,000 psi) no Gas well? yes 3G NACE MR0175? yes no High H 2 S concentration? yes Rated working pressure >34.5 MPa (5,000 psi) Gas well? yes 3 3G no no 34.5 MPa (5,000 psi) no 3 2 Gas well? yes Rated working pressure >34.5 MPa (5,000 psi) 3 no 34.5 MPa (5,000 psi) 2 Rated working pressure >34.5 MPa (5,000 psi) 2 Rated working pressure >34.5 MPa (5,000 psi) Gas well? yes 34.5 MPa (5,000 psi) MPa (5,000 psi) no 2 1 9

13 API 6A, Table 39 API Marking Requirements and Locations Location Marking Wellhead Equipment Connectors and Fittings Casting and Tubing Hangers Loose Connectors Valves and Chokes Actuators API 6A / ISO Temperature class or rating (4.2.2) (actuators containing retained fluid) Material class (4.2.3) (actuators containing retained fluid) Product specification level (1.4) (actuators containing retained fluid) Performance requirement level (4.1) Nominal size (bore if required) or body, and OD or body, and OD Thread size (threaded products only) or body, and/or near each thread or body, and/or near each thread and/or near each or body, and/or near each thread End and outlet size or body, and each OD or body, and each OD Rated working pressure (4.2.1) or body, and each OD or body, and each OD or body, and each OD Ring gasket type and number Near each Near each Near each Date of manufacture Manufacturer s name or mark Serial number (if applicable) 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

14 API 6A, Table 17 Parameter Quality Control Requirements Bodies, Bonnets, End and Outlet Connections, and Hub End Connectors Subclause Reference PSL 1 PSL 2 PSL 3/3G PSL 4 Tensile Testing Impact Testing Hardness Testing NACE MR Dimensional Verification Traceability Chemical Analysis Visual Examination Surface NDE Weld NDE General No welding permitted except for weld overlays (see ) Serialization Volumetric NDE Note: Stems, Hangers and Valve Bore Sealing Mechanisms have their own tables. Thread Markings The thread type marking in accordance with ISO shall be as follows: STC LC BC XL LP NU EU Casing: short thread Casing: long thread Casing: buttress Casing: extreme line Line pipe Tubing: nonupset Tubing: external upset 11

15 API 6A, Table 18 Quality Control Requirements for Welding Bodies, Bonnets, and End and Outlet Connections Weld Type Stages PSL 1 PSL 2 PSL 3/3G PSL 4 Pressurecontaining Nonpressure containing Pressure containing repairs Weld metal overlay partial overlay Weld metal overlay full overlay Note: Preparation Visual Completion Visual Surface NDE Volumetric NDE Hardness test Preparation Visual Completion Visual Hardness test Preparation Surface NDE Completion Visual Surface NDE Volumetric NDE Hardness test Preparation Surface NDE Completion Surface NDE Preparation Visual Completion Visual Surface NDE Volumetric NDE no welding permitted no welding permitted no welding permitted Preparation refers to surface preparation, joint preparation, fit up and preheat. Completion refers to all welding, postweld heat treat and machining, except for volumetric NDE, which shall done prior to machining that would limit effective interpretation of results. 12

16 Relative Corrosivity There are many factors that contribute to the corrosivity of a system. The most prominent of these are: a) Temperature b) H 2 S (Partial Pressure) c) ph d) Chloride ion concentration e) Water production and composition f) Types and relative amounts of produced hydrocarbons g) Oxygen levels h) CO 2 levels (Partial Pressure) 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 produced fluids 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 CO 2 Partial Pressure Retained Fluids Retained Fluids Retained Fluids Mpa Retained Fluids (psia) General service Noncorrosive <0.05 (<7) General service Slightly corrosive 0.05 to 0.21 (7 to 30) General service Moderately to highly corrosive >0.21 (>30) Sour service Noncorrosive <0.05 (<7) Sour service Slightly corrosive 0.05 to 0.21 (7 to 30) Sour service Moderately to highly corrosive >0.21 (>30) Factors Affecting Behavior in H 2 S Containing Environments The behavior of carbon and low alloy steels in H 2 S containing environments is affected by complex interactions of parameters, including the following: a) Chemical composition, method of manufacture, product form, strength, hardness of the material and its local variations, amount of cold work, heat treatment condition, microstructure, microstructural uniformity, grain size and cleanliness of the material b) H 2 S partial pressure or equivalent concentration in the water phase c) Chloride ion concentration in the water phase d) Acidity (ph) of the water phase e) Presence of sulphur or other oxidants f) Exposure to production fluid 13

17 Severity of Sour Environment determined in accordance with NACE MR0175/ISO with respect to SSC of a carbon or low alloy steel kpa (0.05 psi) 1 in situ ph Key 0 Region 0 1 SSC Region 1 2 SSC Region 2 3 SSC Region H 2 S partial pressure, kpa In defining the severity of the H 2 S containing environment, the possibility of exposure to unbuffered condensed aqueous phases of low ph during upset operating conditions or downtime, or to acids used for well stimulation and/or the back flow of stimulation acid after reaction should be considered. Note 1: The discontinuities in the figure below 0.3 kpa (0.05 psi) and above 1 MPa (150 psi) partial pressure H 2 S reflect uncertainty with respect to the measurement of H 2 S partial pressure (low H 2 S) and steel s performance outside these limits (both low and high H 2 S). Note 2: Guidance on the calculation of H 2 S partial pressure is given in Annex C. Note 3: Guidance on the calculation of ph is given in Annex D. The cracking behavior of CRAs and other alloys in H 2 S containing environments can be affected by complex interactions of parameters, including the following: a) Chemical composition, strength, heat treatment, microstructure, method of manufacture and finished condition of the materials b) H 2 S partial pressure or equivalent dissolved concentration in the water phase c) Acidity (in situ ph) of the water phase d) Chloride or other halide ion concentration e) Presence of oxygen, sulphur or other oxidants f) Exposure temperature g) Pitting resistance of the material in the service environment h) Galvanic effects i) Total tensile stress (applied plus residual) j) Exposure time These factors shall be considered when using this part of NACE MR0175/ISO for the selection of materials suitable for environments containing H 2 S in oil and gas production systems. 14

18 The API Monogram In order to receive the authorization for applying the API monogram, StreamFlo s facilities and our quality management system are audited, approved and licensed by the American Petroleum Institute. The API monogram and license number are our customers assurance that StreamFlo is in compliance with all the applicable API requirements, and it signifies to our customers that they are receiving good quality products and services. Performance Validation Certificate 6A0053 Certificate 6D0008 The performance requirements apply to all products being manufactured and delivered for service. The performance verification procedures are to be applied to designs of products, including design changes. Verification testing specified is intended to be performed on prototypes or production models. A design that undergoes a substantive change becomes a new design requiring performance verification. A substantive change is a change identified by the manufacturer which affects the performance of the product in the intended service condition. This may include changes in fit, form, function or material. 15

19 Criteria for Ordering, 20th Edition Pressure Class API holds user responsible for choosing class Temperature Class API holds user responsible for choosing class Material Class API holds user responsible for choosing class PSL (Product Specification Level) API recommends PSLs to the user PR (Performance Requirement) API requires cycle testing of designs When ordering, please use this wellhead equipment data sheet. Well names and location(s): PSL: PR Level: Material Class: Rated Well working names pressure: and location(s): Maximum operating pressure: Temperature Maximum ranges operating anticipated: pressure: Minimum Anticipated flowing wellhead fluid temperature shutin pressure: at wellhead: Anticipated Temperature completion ranges anticipated: or future work over or recovery operations which would affect pressure, temperature or fluid Maximum content: flowing fluid temperature at wellhead New Anticipated values: composition of produced fluids: CO 2 (mg) Chlorides Are (mg) there any government H 2 S regulations that (mg) apply or must be other met by this equipment? Yes No If so, Anticipated which one(s)? completion or future workover or recovery operations which would affect pressure, Water temperature or brine ph: or fluid content: Will New scale, values: paraffin, corrosion or other types of inhibitors be used? Yes No Inhibitor Are there type: any government regulations that apply or must Inhibitor be met carrier: by this equipment? Batch If so, or which continuous one(s): inhibition? Will Water acidification or brine be ph: performed? Yes No Type of Acid: Anticipated rates: m Does NACE MR0175 apply? 3 /d Oil/Condensate m Will scale, paraffin, corrosion or other types of inhibitors be used? 3 /d Gas m 3 /d Sand and Water (S&W) Inhibitor type: Inhibitor carrier: Batch or continuous inhibition? Steam Volume Will acidification be performed? Type of acid: Will Anticipated erosion be a production concern? rates: Yes No Anticipated m3/d oil/condensate cause: External coating? Yes No Type: m3/d gas Internal coating? Yes No Type: m3/d sand and water (S&W) Delivery requirements: Will erosion be a concern? Cause: Special shipping, packing and storage instructions: Anticipated External coating? wellhead shutin Yes pressure: type No Does Internal NACE coating? MR 0175 apply? Yes type Yes No No Anticipated Delivery requirements: composition of produced fluids: CO 2 : H 2 S: Special shipping, packing and storage instructions: Chlorides: Other: Other Comments / Information: Casing Program Casing Program Top Joint in String Top Joint in String Size (OD) kg/m (lb/ft) Grade Connection Total String Bit Size Size (OD) kg/m (lb/ft) Grade Connection Total String Hanging Hanging WT WT mm Bit (in) Size dan dan (lbs) (lbs) mm (in) Conductor Conductor Surface Casing Protective Casing Casing Production Production Casing Casing Tubing Tubing Completion Type: single or multiple Type of Completion: Single Multiple For more For information, more information, please please contact contact StreamFlo StreamFlo at (403) at (403) or or info@streamflo.com. 16

20 Head Office and Manufacturing Facility Avenue Edmonton, Alberta, T6B 2H5 t f Sales and Marketing Office 400 Bow Valley Square One Avenue SW Calgary, Alberta, T2P 2R9 t f United States Wellhead & Valve Business Units 8726 Fallbrook Drive Houston, Texas USA t f StreamFlo Middle East DMCC Unit 2404, Swiss Tower, Jumeirah Lakes Towers Sheikh Zayed Road Dubai, United Arab Emirates PO Box: 2562 t f WORLDWIDE EXPERTISE GLOBAL STRENGTH The StreamFlo Group of Companies