【正文】 ................................................................................................................. 32 3 General rules The code applies to the configuration, construction and acceptance of following pipes of thermal power plant and thermal power work: The main steam pipes of 600MW or lower subcritical parameter thermoelectric generating set and corresponding reheating steam pipes and main water supply pipes。 General steam and water pipes, thermal power work pipes and pressed air pipes in thermal power plant。 Temporary pipes used in construction. The code does not apply to the following: Cast iron pipes。 Reinforced concrete pipes。 Nonferrous (titanium, copper and etc.) pipes。 Nonmetal (plastic and etc.) pipes。 Nonmetal lining pipes。 Composite metal pipes. For the special construction and acceptance of following types of pipes, regulations in corresponding section of the Code of Erection and Acceptance for Electric Rower Construction should be also plied besides the technology requirements in this code: All types of pipes in the steam turbine and electric generator body。 All types of pipes in boiler body, and pipes of fume exhaust system, ventilation system, coal system, fuel system, gas burning system and dust removal system。 Oil pipes and all types of water treatment pipes。 All types of pipes of hydrogen generating system and hydrogen supply system。 Thermal meter pipes。 Oxygen and acetylene pipes. Except the sections with other concrete stipulations in construction contract, the provisions in this code must be observed in the construction and acceptance of pipes of imported thermoelectric generating set. The piping installation of power plant must be carried out by professional construction team with essential technical force, checking means and management level. The piping construction of power plant should be carried out according to the basic construction program, and following conditions are necessary: Designing files and other technology documents should be fully ready, and a joint checkup must have been made for construction drawings。 The construction anizing design and construction plan of piping project of electric power plant should have been piled, checked and approved。 Real technology munication and required technical training and examining should have 4 been finished。 Labor force, materials, machineries and checking means should be pleted on the whole。 Construction should satisfy the demands of environment。 Water, power and pressed air used in construction sho uld satisfy the demands of construction. Active national or trade (or special) technical standards must be plied for the manufacturing quality and choosing of pipes, pipe fittings and pipe accessories. Active SDJ68 the Maintenance and Keeping Regulation for Electric Power Basic Construction Thermal Power Devices and corresponding additional regulations should be observed for the store of all types of pipes, pipe fittings and pipe accessories. All types of pipe should be constructed according to the design drawings, and it should be submitted t designing unit to treat in term of relevant regulation if the design should be modified or substitute material should be adopted. The relevant regulation in active DL 5007 the Code of Erection and Acceptance for Electric Power Construction (Welding Section of Thermal Power Plant) should also be observed in the cutting and welding operation f pipes construction besides the relevant regulations in this code. Regulations in SDJ 245 the Code of Erection and Acceptance for Electric Power Construction (Boiler Unit Set Section) should be plied 1ir the heat preservation and painting of pipes. And the painting of pipe should be carried out according to the regulation of DL 50I I the Code of Erection and Acceptance for Electric Power Construction (Steam Turbine Unit Set Section). Relevant regulations of active DL the Safety Operating Regulation of Electric Power Construction (Thermal Power Plant Section) must be observed for the safety, environment and fire protection in the piping construction of electric power plant. 5 Glossary Pipe fittings the general designation of parts and elements which posing piping system with pipes together, including elbow, elbow pipe, tee pipe, converging tube, pipe connecting saddle, flange, dead end, end plate and etc. Pipe accessories external supporting parts of piping system, including supporting and suspending bracket, shim, sealing parts, fastening parts and so on. Elbow piperefers to the pipe with bending axial line. Elbow refers to the elbow pipe which bending radius is no more than 2D, and straight section is less than 10. Miter elbow elbow made up of two or more straight pipe sections which welding together in the plane of equal bend angle (also called welding elbow or shrimp elbow). Calculation wall thickness of straight pipe the Min. wall thickness of straight pipe plus the negative deviation value of the wall thickness of straight pipe. Monitoring section pipe section used to monitor creep, which installed on horizontal section of main steam .pipes that designing temperature is above 4500C, or reheating high temperature steam pipes. Creeping expansion measuring point equipments or marks to measure the creep deformation of pipes, which installed on motoring section pipes or steam pipes Pipe classification electric power plant pipes can be classified according to designing pressure p as main parameter, refers to table . Table Pipe classification Pipe classification Main parameter High pressure pipe p8 MPa Medium pressure pipe 8 MPa≥p MPa Low pressure pipe p≤ MPa Note: reheating section and heating section pipes should be looked upon as high pressure pipes. Checking of pipes,