DL/T 438-2016 in English

Scope

This standard specifies the scope of components for metal supervision in thermal power plants, the items, contents and corresponding criteria of inspection and supervision. The inspection and supervision of metal parts of waste heat boilers, steam turbines and generators of gas turbine power plants can be implemented with reference to this. This standard applies to the supervision of the following metal components: a) High-temperature pressure-bearing components with operating temperatures higher than or equal to 400°C (including main steam pipes, high-temperature reheat steam pipes, superheater tubes, reheater tubes, headers and tees ), and small tubes connected to pipes and headers. b) Steam guide pipes and contact pipes with working temperatures higher than or equal to 400°C. c) Steam-water separators, water storage tanks and pressure vessels of drums and once-through boilers with working pressures higher than or equal to 3.8MPa. d) Pressurized steam and water pipes and components with a working pressure higher than or equal to 5.9MPa (including cold wall pipes, economizer pipes, headers, desuperheating water pipes, drainage pipes and main water supply pipes). e) Steam turbine shaft, impeller, blades, rags, bearings and generator shaft, retaining ring and fan blades. f) Bolts with working temperature higher than or equal to 400℃. g) Cylinders, steam chambers, main valves, regulating valves, nozzles, partitions, partition sleeves and valve housings with operating temperatures higher than or equal to 40°C. h) Low-temperature reheat steam pipelines with longitudinal welds for units of 300MW and above. i) Boiler steel structure.