SC6 Ballot 1974: Adopt-back of ISO 10423:2009 as API 6A 20th ed. Task Group Report on Resolution of Ballot Comments Eric Wehner 30 June 2010 • Issue 1: Normative references, latest edition • Comment: It can be impossible for manufacturers to comply with a revision to a normative reference unless some time period for implementation is allowed. • Proposed change: Replace the last sentence of Clause 2 with: "For undated references, the latest edition of the referenced document (including any amendments) applies." with: "For undated references, the latest edition of the referenced document (including any amendments) applies, except that new editions may be used on issue and shall become mandatory 6 months from the date of the revision." • TG Resolution: Comments accepted: – Revise Clause 2 as proposed. – NOTE: This is in 6A 19th edition, Annex O. • Issue 2: ASTM A703 reference • Comment (a): Normative reference ASTM A703/A703M-08a is a dated reference; should be an undated reference. • Comment (b): Casting coupons referenced in 5.6.2c) do not match. • TG Resolution: Comments accepted: – Delete "Figure 1" in 5.6.2 c). – Revise 5.6.2c) to read: "-casting: size not required to exceed size specified in ASTM A703/A703M.” – Change ASTM A703/A703M to undated reference in Clause 2. • Issue 3: Nuts for insulated flanges • Comment: Both the stud and nut used on insulated flanges should meet exposed bolting requirements. • Proposed change: Require Grade 2HM nuts. • TG Resolution: Comment rejected: – TG group believes that allowing Grade 2H nuts for exposed bolting is intentional and has been shown to be acceptable . – TG recommends that the topic of bolt and nut materials for sour service and/or for insulated flanges should be addressed as a NWI. • Issue 4: Use of Grade L7M nuts • Comment: ASTM A194 requires impact-tested nuts when low-temp fasteners, ASTM A320, are specified. However, API 6A requires use of lowtemp bolting excluding nuts at temperature class L (-50C). • Proposed change: Add 4L, 7L and 7ML grade nuts to Table 62 . • TG Resolution: Comment accepted in part: – TG agrees that ASTM A194/A194M grade 7M should be added to 10.3.3.5a) and Table 62 as an additional acceptable grade for nuts for all classes, both exposed and non-exposed. • Issue 5: Flange design criteria • Comment: The design method used by API for flanges is not specified or referenced. • Proposed change: Add reference to API design criteria and methods in 18.104.22.168. • TG Resolution: Comment rejected, however: – TG proposes to add the following to 22.214.171.124: "NOTE: Information on design analysis and load capacities of flanges specified in this International Standard can be found in API Technical Reports 6AF, 6AF1, and 6AF2." • Issue 6: Design acceptance criteria • Comment: ASME allowable stress at test pressure should be 0,9 SY, not 0,83 SY (5/6). • Proposed change: Replace ST = 0,83 Sy with ST = 0,9 SY , to match API 16A. • TG Resolution: Comment rejected: – No consensus reached in TG for revision – TG recommends consideration of a NWI to develop a standard for design verification (methods and criteria) for drilling and production equipment (SC6, SC16, SC17). • Issue 7: Bolt design criteria • Comment: A limit is needed on membrane plus bending stress in studs. • Proposed change: Revise 4.3.4 to allow bolt stress at test pressure = 0,9 SY, and add SB as the maximum membrane plus bending stress in the bolting. • TG Resolution: Comment rejected, however: – Revise second sentence to read: "Bolting tensile stress, based on the minimum crosssectional area of the bolting, shall not exceed the limit given in Equation (9):" • Issue 8: Castings for PSL 3/3G • Comments (3 voters): There is no technical justification and or product performance data to support the prohibition of castings for PSL 3. • Proposed change: Reinstate the following subclauses from Annex O of 6A 19th edition: 126.96.36.199 b), 188.8.131.52 c), 184.108.40.206.15 b) 1), 220.127.116.11.15 c) 1), 18.104.22.168.15 c) 2). • TG Resolution: Comments accepted: – Revise referenced subclauses to permit castings for PSL 3/3G bodies, bonnets, end & outlet connections. – Retain “wrought material only” for PSL 4 BBEC and for PSL 3-4 mandrel tubing and casing hangers. • Issue 9: Pressure-controlling parts • Comment: No general quality requirements are provided for pressure controlling parts other than valve bore sealing mechanisms, choke trim and hangers. • Proposed change: Revise 7.4.10 and Table 37 to apply to casing and tubing hanger mandrels and other pressure controlling parts • TG Resolution: Comment noted: – TG suggests that the definitions and requirements for pressure-controlling and pressure-containing parts should be reviewed in detail and possible revisions proposed, as a NWI. Note: This could include Clauses 4, 5, 6, 7, and 10. • Issue 10: Table reference error • Comment: Wrong table is referenced in 22.214.171.124.4c). • Proposed change: Replace “Tables 48 and B.48” with "Tables 61 and B.61." • TG Resolution: Comment accepted: Correct the table reference in 126.96.36.199.4c) as proposed. • Issue 11: SSV/USV designation • Comment: Incorrect designation of SSV/USV valves is used in A.9. • Proposed change: Change “Performance test agency (PR2 SSV/USV Valves)” to “Performance test agency (Class II SSV/USV Valves).” • TG Resolution: Comment accepted: Correct A.9 as proposed. • Issue 12: New temperature ratings • Comment: Minimum temperature of 0 °F imposes unnecessary requirements for tropical climates where ambient temperatures may not fall below 60 °F. • Proposed change: Add to Table G.1: XR as Room Temp to 350 °F and YR as Room Temp to 650 °F • TG Resolution: Comment rejected, however: – 188.8.131.52 of 10423:2009 includes new provision for "minimum and maximum temperatures as agreed between the purchaser and manufacturer." Marking requirements in 8.1.1 have been similarly modified. • Issue 13: Use of HP VR plugs for < 15,000 psi • Comment: Annex L should be informative, or 6A should allow the use of HP VR plugs in 2-ksi thru 10-ksi equipment. • Proposed change: Revise 8.10, 10.22, and Annex L to permit HP VR plugs in all pressure ratings. • TG Resolution: Comment noted: – No consensus reached in TG for revision. Task group recommends NWI in SC6 to establish VR/HP VR standards, with revisions as deemed appropriate. • Issue 14: Spec 6AV requirements • Comment: Incomplete carryover of 6AV1 requirements into 6A. • Proposed change: – Change I.1.4 to read: "The successful completion of the test shall qualify all sizes and all pressure ratings of that manufacturer's SSV/USV of the same basic design and materials of construction for the intended class of service." – Also, remove NOTE following I.1.4. • TG Resolution: Comment accepted: Revise I.1.4 as proposed. • Issue 15: Annex J Scope • Comment: The phrases "user/purchaser owned... equipment" and "for continued service by the user/purchaser" and "not applicable to... equipment intended for resale" are commercial restrictions, not technical requirements. • Proposed change: – Revise to read: "Annex J defines the requirements for repair and remanufacture of wellhead and christmas tree equipment originally manufactured in accordance with this International Standard. Field repair, with or without the replacement of parts and modification of equipment is outside the scope of this annex." – NOTE: This is the wording used in Annex B of API Spec 16A, Specification for Drill-Through Equipment. • TG Resolution: Comment rejected: No consensus reached in TG for revision. • Issue 16: VR and HP VR thread gauging • Comment: For VR plugs and preps L.6 says these “may” be inspected, not required. • Comment: For L.6.2 there is no requirement to gauge the HP VR preparation, only the plug. • TG Resolution: Comments accepted in part: – Add at the beginning of L.6.1; "VR plugs and plug preparations shall be dimensionally inspected." – Revise L.6.2 to read: "HP VR plugs and plug preparations shall be dimensionally inspected. Inspection methods shall be in accordance with the manufacturer's documented procedures.“ – Note that 184.108.40.206 applies to VR and HP VR plugs, and requires all threads or retention profiles to be gauged.