(1) Quality control of the main body blank All parts of this valve are forgings, and the forging is carried out in strict accordance with the forging process regulations and process cards, and the initial forging temperature, final forging temperature, deformation degree and deformation speed are strictly controlled. Cooling method for cooling. The chemical composition analysis, mechanical property test, intergranular corrosion test, and metallographic structure analysis of the forging products are carried out. After analysis, test and measurement, they all meet the corresponding standards.
The quality of the forgings is guaranteed by ultrasonic inspection and liquid penetrant inspection. According to the requirements of RCC-M, 100% ultrasonic flaw detection and evaluation are carried out on the forgings, and liquid penetrant inspection and evaluation are carried out on the entire surface of the forgings.
(2) Welding In order to improve the quality of surfacing welding, the surfacing welding of the sealing surface of the valve disc and the valve seat adopts the plasma argon arc welding process. At the same time, in order to ensure the welding quality, the welding process used in production was re-qualified.
(3) Assembly test High-quality products not only require high-precision parts, but also how to assemble these high-precision parts into high-performance products. CNNC Su Valve has organized an experienced and skilled assembly and debugging team composed of many technicians and senior technicians. Strictly check and debug, keep improving, ensure the valve assembly and debugging are successful, and carry out various performance tests, all indicators are in line with the requirements of the design task book.
(4) Process inspection A quality plan has been prepared for the valve to ensure that the valve has been quality controlled from raw materials, blank input, machining, welding, heat treatment, non-destructive testing, cleaning, assembly, factory testing and various type tests, and has been approved. Accredited and witnessed by the Second Industrial Research and Design Institute.
Butterfly double flap check valve is suitable for high-rise building water supply pipeline network, pipeline network with certain chemical corrosive medium, pipeline network with limited installation space, and also suitable for sewage pipeline network.
The lift-type silent check valve is suitable for the pipeline network with high quality requirements for water supply and drainage projects; the pipeline network with relatively high pressure requirements (PN2.5Mpa); it can be installed at the outlet of the pump and is an economical and practical waterproof hammer check valve.
The lift-type silencing check valve is suitable for water supply and drainage system and high-rise building pipe network. It can be installed at the outlet of the pump. The structure is slightly modified. It can be used as a suction bottom valve, but it is not suitable for sewage pipe network.
Horizontal check valve is suitable for submersible, drainage, sewage pump, especially suitable for sewage and sludge system.
Swing rubber check valve is suitable for domestic water pipe network; but not suitable for sewage with a lot of sediment
Swing single flap check valve is suitable for water supply system, petroleum, chemical industry, metallurgy and other industrial sectors, and is most suitable for places with limited installation space.