The principle of practical application of plug valve
The plug valve is a closed or plunger-shaped rotary valve, which can be opened or closed by rotating 90 degrees to connect or separate the channel opening on the valve plug and the channel opening on the valve body. Its valve plug can be cylindrical or conical in shape. In cylindrical plugs, the passages are generally rectangular; in conical plugs, the passages are trapezoidal. These shapes allow for a lightweight construction of the plug valve. It is most suitable for shut-off and connection medium and for diverting, but can also be used for throttling depending on the properties of the application and the erosion resistance of the sealing surface.
According to the structural characteristics of the plug valve and the functions that can be achieved in the design, it is recommended to select according to the following principles:
1. It is recommended to use austenitic stainless steel ground-tight conical plug valves for equipment and pipelines in food companies such as milk, juice, beer, and pharmaceutical factories.
2. It is used to distribute the medium and change the flow direction of the medium. The working temperature is ≤300℃, the nominal pressure is ≤1.6MPa, and the nominal passage is ≤300mm. It is recommended to use a multi-channel plug valve.
3. In the pipelines and equipment of gas, natural gas and HVAC systems, when the nominal pressure is less than or equal to 1.0MPa and the nominal diameter is less than or equal to 200mm, the packing type conical plug valve should be selected.
4. In the branch pipes, refining and cleaning equipment of oil field exploitation, natural gas field exploitation, pipeline transportation, the nominal pressure level is ≤ CL300, the nominal diameter is ≤ 300 mm, and the working temperature is ≤ 340 °C, it is recommended to use oil-sealed conical plug valves.
5. In the branch pipes, scouring and cleaning equipment for oil field exploitation, natural gas field exploitation, pipeline transportation, the nominal pressure level is ≤ CL2500, the nominal diameter is ≤ 900 mm, and the working temperature is ≤ 340 °C. It is recommended to use a pressure-balanced inverted conical plug valve.
6. In the large-scale chemical industry, in the pipelines and equipment containing corrosive media, where the opening or closing speed is required to be fast, for the medium based on nitric acid, 1Cr18Ni9 stainless steel PTFE sleeve can be used to seal Conical plug valve; for acetic acid-based media, Cr18Ni12Mo2Ti stainless steel PTFE sleeve sealing conical plug valve can be used.
Guangdong Jinshang Intelligent Electric Co., Ltd. has continuously reformed and innovated on the basis of fully introducing and absorbing foreign advanced technology, and has successfully developed and produced valve series products for the core system of gas appliances, which are widely used in outdoor ovens, heaters, wall-hung boilers, gas appliances, etc. at home and abroad. On many products such as ovens, the company has always implemented the IS09001 quality management system and strictly implemented the "7S" management standard.