S9074-AR-GIB-010/278
Where post weld heat treatment is required by component or equipment specifications, or where design service temperature exceeds 400°F, only the above listed A-43A or A-43B filler metals shall be used. 6.2.5.1.4 6.2.5.1.4 For surfacing applications to resist stem cutting. the filler metals specified in 6.2.5.1.3 may be used on base materials under groups S-1, S-3, S-3A, S-4, S-5, S-6 and S-7. Where subsequent post heat treatment of these base materials is required, only the MIL-8BN12, EN-82, and RN82 filler metals shall be used. 6.2.5.1.5 For welding the dissimilar metal combinations of S-10H to S-11 or S-2 alloy steels, the electrode for shielded metal-arc welding shall be MIL-1N12 OF MIL-E- 22200/3 and for gas metal-arc and gas tungsten-arc welding the filler metal shall be MIL-EN625 or MIL-RN625 of MIL-E-21562 as applicable. 6.2.6 Number of weld passes. Unless otherwise approved, no less than two layers shall be used for all pressure containing weld joints. 6.2.7 Weld back side shielding. Inner root surface of all consumable insert type welds and all full penetration butt welds not employing a backing ring shall be shielded by inert gas. Internal purge shall be continued until after completion of the third layer or a thickness of 3/6 inch, whichever is greater. This requirement does not apply to P-2 type weld joints in P-2 piping systems of materials other than authorized representative that the interna surface of the weld meets the visual requirements of MIL-STD-2035. 6.2.7.1 When welding in or to titanium or titanium alloys (including repair welding of base metal and welds) the weld area backside shall be shielded with the inert gas unless the backside temperature is determined to remain less than 500°F. Shielding shall continue until completion of welding. Temperature shall be determined by checking actual backside surfaces during welding with pyrometers or other suitable means, or if the area is inaccessible for measurement, a mock-up of the weldment heat sink stimulating worst case production conditions shall be welded. Temperature measurements shall be obtained from the mock-up weld backside area as necessary to demonstrate that temperatures will remain below 500°F during all production welding. A description of the mock-up and welding and temperature test shall be maintained with the welding procedure qualification records.
6.2.8 Age hardenable alloys. Welding of age hardenable alloys is subject to NAVSEA approval. 6.3 Preheat and interpass temperatures. Preheat and interpass temperatures shall be as specified in tables IV and V unless otherwise approved by welding procedure qualification.
See footnotes at end of table.
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