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Heat-treated specimens: The regulations regarding heat-treated specimens are as follows: 01 When heat treatment is required during the manufacturing process to restore or improve the mechanical properties of the material, heat-treated specimens of the base material shall be prepared. 02 When preparing heat-treated test pieces of the base material, if it is also necessary to prepare welding test pieces of the product, it is allowed to fabricate both types of test pieces together. 03 Specimens for heat treatment of the base material shall be prepared in any of the following cases: a) When it is required that the material be used in its heat-treated state as delivered, and if the heat-treated state at delivery is altered during manufacturing, reheat treatment is necessary ； b) During the manufacturing process, heat treatment is required to improve the mechanical properties of the material ； c) Compression members formed by cold forming or warm forming, which require heat treatment to restore the material properties after formation. 04 The heat-treated specimens of the base material should be heat-treated in the same furnace as the base material ； When it is not possible to heat treat in the same furnace, the same heat treatment condition as the base material should be simulated. Class III containers: The mandatory requirements for Class III containers are as follows: 01 For externally purchased Class III pressure vessels made from Grade IV forgings, the manufacturing unit must conduct re-inspection; they can only be put into use after passing this inspection. 02 For the design documents of Class III pressure vessels, in addition to the three levels of signing for design, verification, and review, they must also be approved by the technical responsible person of the pressure vessel design unit or their authorized representative (level 4 signing). 03 For Class III pressure vessels, the design unit shall issue a risk assessment report that includes information on major failure modes and risk control. 04 The weld joints between the flange and the shell, as well as those of the jacketed pressure vessel, shall adopt a fully penetrated structure. 05 For Class III pressure vessels with a design pressure of 1.6 MPa or greater, their Class A and Class B weld joints shall undergo 100% non-destructive testing (RT/UT/TOFD).