S9074-AR-GIB-010/278 Table VI-Post Heat Requirements for Welded ferrous alloys
Applicable supplementary provisions and exceptions
Pressure vessels, turbines classes A-F, A-LT, A-1, A-2, A-3, A- 4, T-1, and T-2
Holding Tempera ture *F 2/, 3/
Material Group Number
Material Identifica tion 1/ High alloy austenitic steel
Machinery class M 1/
Piping Class P
Weldments of austenitic corrosion resistant steel shall not be post-weld heat treated unless otherwise specified herein or in the controlling component specification. Annealing or solution treating of austenitic corrosion resistant steel shall be done only for putting precipitated carbides back into solution and only for those weldments that can be entirely water quenched immediately after heating. When such heat treatment is required, the weldment shall be heated to a temperature of between 1950 and 2050*F, held at that temperature for 1 hour for each inch or fraction thereof of thickness at the thickest part, and then the entire weldment shall be water quenched. Post weld heat treatment of CN-7M or CN-7MS stainless steel castings is required to restore the corrosion resisting properties of the material. Heat treatment shall consist of heating the casting to 2050*F minimum, hold for sufficient time to heat the casting to temperature, and the quench in oil or water. However, post weld heat treatment is not required for welding on the nonwetted surface (casting surface which is not exposed to sea water) where such welding can be accomplished without causing any portion of the wetted surface to be heated to a temperature exceeding 800*F. Weldments of duplex stainless steel shall not be post-weld heat treated unless otherwise specified herein or in the controlling component specification. Annealing or solution heat treating shall be done only for putting precipitated carbides or sigma phase back into solution and only for those weldments that can be entirely water quenched immediately after heating. When such heat treatment is required, the weldment shall be heated to a temperature of between 1900 and 1975*F, held at that temperature for 1 hour for each inch or fraction thereof of thickness at the thickest part, and then the entire weldment shall be water quenched. When this option is exercised, test samples shall be removed from the heat treated parts, or test coupons from the same heat and lot as the heat treated subassemblies and heat treated with the parts, shall be tested as required by the base material specifications. The heat treatment procedure, including the mechanical test specimen requirements, shall be submitted for approval.
S-8
-
High alloy duplex stainless stee
S-10H
-
Original 66
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