S9074-AR-GIB-010/278
6. WELDING REQUIREMENTS AND CONTROLS 6.1 General. This section contains the requirements or controls that are essential for ensuring satisfactory welds in machinery, piping, pressure vessels, and steam turbines hereinafter referred to as M, P, A, and T. 6.1.1 Gas metal-arc welding - short circuiting transfer (GMAW short arc) restriction. This process shall not be used unless approved otherwise for a specific application, on a case-by-case basis, by NAVSEA. 6.1.2 Non-structural welds such as name plates, clips and insulation supports on class P-1, P-LT, A-F, A-1, A-2, A-3, A-LT, T-1, and M-1 components shall be made by welders qualified for butt or fillet welds. These welds shall be inspected in accordance with section 10. 6.1.3 Autogenous welding shall not be used for S-10H materials. 6.2 Welding processes and filler materials. Acceptable welding processes and compatible filler materials are shown in table III. Specific filler materials for steam service applications shall be in accordance with 6.2.5.1. Processes and materials not listed in table III. and material not in accordance with 6.2.5.1 shall be permitted where applicable welding procedure qualification data are approved by NAVSEA and authorized for the particular production applications. Aluminum alloys shall be welded only by the inert gas metal-arc and the inert gas tungsten arc processes. The root pass of S-8 piping welds in which the reverse side of the weld cannot be visually examined and is exposed to water shall be welded with a gas shielded welding process. Inert gas shielding is also required for S-51, S-52, and S-53 materials as required in 6.2.7. 6.2.1 Oxyacetylene restrictions. Except as permitted by 11.6, oxyacetylene or fuel gas welding processes shall be used for welding on chromium-molybdenum (S-4, S-5) chromium alloy (S-6, S-7) chromium nickel (S-8), quenched and tempered alloy steels (S-11), and aluminum or aluminum alloys (S-21, S-22, S-25 and S-26). 6.2.2 Class P material thickness limitation. The shielded metal arc process may be used for wall thickness of 0.109 inch or over when welded on board ship and 0.083 inch or over when welded in the shop. Other welding processes will be permitted for thinner walls on the basis of welding procedure qualification tests. 6.2.3 Covered electrodes for class P-1 carbon steel pipe. Class P-1 carbon steel pipe shall be welded with electrodes types MIL-7018, MIL-7018M, MIL- 70180-A1, MIL-7015 or MIL-7016 (A-2A) except when nominal wall thickness is 1/2 inch or less MIL-7010-A1 electrodes A-1A may be used. 6.2.4 Prohibited electrodes. Unless specifically approved, types MIL-6010, 6012 or 6013 electrodes of AWS A5.1 shall not be used for M, P, and A applications.
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