7　Piping of Steam Turbine

7.1　General Provisions

7.1.1　This Chapter is applicable to the works of pipes and fittings in the steam，condensate，air，steam seal，drain，vacuum water seal and bypass systems within the set design scope for steam turbine.

7.1.2　The construction and welding of piping within the scope of steam turbine shall be in accordance with the relevant provisions in Part 5"Pipes and systems"of this Specification，"Code of welding for fossil fuel power plants"DL/T 869 and"Code of welding for conventional island in nuclear power plants"DL/T 1118.

7.1.3　Before assembling of alloy steel piping and fittings of the pipes in the scope of steam turbine，spectrum inspection shall be performed，and the materials be checked again and records be made.For high alloy steel materials likely to produce crack，such as T91/P91，T92/P92，P911，P122，flame arc spots shall be removed with a grinding wheel or sand cloth in time after inspection.