【正文】 ylene pipe system .................................................. 31 Supplementary instruction: .......................................................................................................................................... 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。 1 ELECTRIC POWER TRADE STANDARD OF THE PEOPLE39。S REPUBLIC OF CHINA THE CODE OF ERECTION AND ACCEPTANCE FOR ELECTRIC POWER CONSTRUCTION PIPING SECTION DL 503194 Chief Editorial Department: Construction Cooperating Department of the Ministry of Power Industry Approved Department: The Ministry of Power Industry of 1994 Beijing 2 Note This book is the English translation of The Code of Erection and Acceptance for Electric Power Construction Piping section DL 503194 In the event of any inconsistency between the Chineselanguage text of the Code and the present Englishlanguage text of the Code, the Chineselanguage text shall be taken as ruling. 1 The Ministry of Power Industry of the People39。 General steam and water pipes, thermal power work pipes and pressed air pipes in thermal power plant。 Reinforced concrete pipes。 Nonmetal (plastic and etc.) 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。 Oil pipes and all types of water treatment pipes。 Thermal meter pipes。 The construction anizing design and construction plan of piping project of electric power plant should have been piled, checked and approved。 Labor force, materials, machineries and checking means should be pleted on the whole。 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, pipe fittings, pipe accessories and valves General regulations Qualified certificate of manufacturer must be provided for pipes, pipe fittings, pipe accessories and valves, and corresponding indexes should be in concordance with active national or trade technical standards, Specification, material and technical parameter must be checked according to the design requirements prior to the using of any pipe, pipe