CJ / T 3049-1995 1 Subject Matter and Scope This standard specifies the gray iron and ductile iron gate valve, butterfly valve, stopcock and stop valve for urban water supply for urban construction industry standard of the People's Republic of China. Design, materials, test methods, marking and general requirements for delivery. This standard is not provided for, should be consistent with the valve product of national standards or industry standards. This standard applies to the nominal pressure PN≤1.6MPa, working pressure Pw≤1.6MPa, the driving mode is manual, electric, hydraulic or pneumatic, as the cut-off or regulating water supply valve in the process of city water, water and water distribution. 2 Standard GB .1 ~ .10 gray cast iron pipe flanges and gaskets GB 9876 rubber seals for the discharge pipe glue GB 12220 universal valve mark GB 12221 flange connection length of the metal valve structure GB 12222 multi-turn valve drive GB 12223 part of the rotary valve drive GB 12226 common valve gray cast iron technical conditions GB 12227 common valve ductile iron technical requirements GB / T 12252 General valve supply requirements GB 12380.1 ~ 12380.6 convex overall ductile iron pipe flange GB / T 13927 General valve pressure test JB / T 5300 General valve material ZB J16 002 Valve electric device technical conditions ZB J16 009 Valve pneumatic device technical conditions 3.1 Housing (including valve body and bonnet) 3.1.1 Shell wall thickness 3.1. 1.1 for urban underground water distribution pipeline feed valve, the nominal diameter DN ≤ 1200mm, the minimum shell thickness should be at least nominal pressure 1MPa pressure level design; DN> 1200mm, the minimum wall thickness of the shell can be According to the nominal pressure of 0.6MPa pressure level design, When Yong Yong special needs, when ordering can be specified by 1MPa design. 3.1.1.2 for urban water supply, water purification, application of urban water supply valve, the minimum wall thickness of the shell should be required by the general valve, without special provisions. 3.1.2 Body 3.1.2.1 flange connection size should be GB 4216.1 ~ 4216.10 or GB 12380.1 ~ 12380.6 regulations. 3.1.2.2 The length of the flange connection valve structure should be implemented according to the provisions of GB 12221. 3.1.2.3 Nominal diameter DN ≥ 800mm gate valve, the valve inlet side of the water should be provided with a sewage tank, sewage tank should be filled with holes or mouth. 3.2 Stem 3.2.1 Stem packing structure design should consider non-stop water replacement, maintenance, and maintenance. 3.3 Operation 3.3.1 Operation direction of valve opening and closing When facing the handwheel or handle, turn clockwise to close the valve and turn counterclockwise to open the valve. Special requirements specified in the order contract. 3.3.2 Opening and closing operating torque When the opening and closing operating torque is greater than 1440N · m, there should be deceleration devices. 3.3.3 Opening and closing indicator 3.3.3.1 In addition to the open-air valve that can show the valve opening, the urban water supply valve with a nominal diameter DN greater than 300mm shall be provided with an opening and closing indicator. The position indicated by the opening and closing indicator should correspond to the degree of opening and closing of the valve. When the operator facing the opening and closing pieces, should be able to clearly observe the degree of opening and closing the valve. 3.3.3.2 The nominal diameter DN is greater than 300mm underground or open-air urban water supply valve, opening and closing indicator transmission part must be installed in a closed protective device. 3.3.3.3 Indicators should be installed securely, properly adjusted, indicating clear, durable. 3.3.4 Opening and closing mechanical limit device Butterfly valve and plug valve for urban water supply, opening and closing terminals should be provided with mechanical limit device, mechanical limit device should be able to withstand 2 times the maximum operating torque of the impact. 3.4 Drive 3.4.1 motor-driven valves, the electric device should be consistent with the provisions of ZB J16 002; for the use of air and other gas-driven valves, the pneumatic device should be ZB J16 009 regulations. 3.4.2 Under normal operating conditions, the maximum control torque generated by the electric device should be greater than or equal to 1.5 times the required torque of the valve, and less than 2 times. 3.4.3 motor drive opening and closing position should be set limit switch and torque switch. 3.4.4 hydraulic drive valve is closed, the hydraulic system should be cushioning device. 3.4.5 For electric, hydraulic, and pneumatic valves such as gate valves and globe valves, the size of the connecting flange of the bracket and the driving device shall comply with the provisions of GB 12222. 3.4.6 For electric, hydraulic and pneumatic valves such as butterfly valves and plug valves, bracket and drive connecting flange size should be consistent with the provisions of GB 12223. 4 Materials 4.1 Town water supply valve All parts, packing and seals shall not be used to tap water pollution caused by the material. Among them, the rubber ring compound should be consistent with the provisions of GB 9876. 4.2 Gray cast iron should be consistent with the provisions of GB 12226; ductile iron castings should be consistent with the provisions of GB 12227. 4.3 The manufacturer should not pollute the water when using special coatings to prevent corrosion. 4.4 stem shall be made of stainless steel containing not less than 11.5% chromium. Cast copper may not be used. 4.5 Fasteners used for valve fixing parts are made of stainless steel. 4.6 opening and closing indicator dial and rotate the pointer, the use of stainless steel and other corrosion-resistant materials. 4.7 Town water supply valves other parts of the material should be JB / T 5300's provisions. 5 Test methods 5.1 Pressure 5.1.1 Test and acceptance of urban water supply valves must be tested one by one, the test medium is water at room temperature. 5.1.2 Before the test, the sealing surface must be cleaned, the seat must not have a thin layer of abrasion to prevent scratches, the air in the chamber should be drained. 5.1.3 urban water supply valve test should be GB / T 13927 regulations. 5.1.4 Non-metallic elastic seal The maximum allowable leakage test of valve sealing test shall be carried out according to Class A requirements of GB / T 13927; the maximum allowable leakage of sealed test of metal sealing valve shall be in accordance with the requirements of Class C in GB / T 13927. 5.2 Drive test Valve with a drive unit, should be assembled in the factory, and open and close at rated pressure test until the performance of the drive qualified. 6 test rules Town water supply valve inspection is divided into factory inspection and type inspection. 6.1 factory inspection 6.1.1 urban water supply valve should be qualified by the factory inspection department, with a certificate before leaving the factory. 6.1.2 urban water supply valve factory inspection should be carried out by Taiwan. 6.1.3 Factory inspection In the contract does not provide for additional items, should include the following: a. Shell test; b seal test c drive test; 6.2 type test 6.2.1 one of the following circumstances, Should be type tested: a. New product trial identification; b. Design, technology, materials and other major changes. 6.2.2 Type inspection should include the following: a. Factory inspection; b. Casting quality inspection; c. Repeated switching operation test, at least 5 times. 7 signs 7.1 signs of urban water supply valve according to the provisions of GB 12220 implementation. 7.2 urban water supply valve signs must be marked on the highest working pressure. 7.3 Town water supply valve type code used in the special "G" said. 8 Packaging, transportation, storage Town water supply valve packaging, transportation, storage according to the provisions of GB / T 12252 implementation.
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