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The low temperature valve has the following performance characteristics:
1, the valve cover is designed as a long neck structure, can isolate the influence of low temperature medium on the packing, can prevent the performance of the cover seal is reduced, but also make the valve open and close flexible;
2, the packing adopts flexible graphite or PTFE combined structure, with good low temperature resistance;
3. Low temperature valve adopts the structure of opening a pressure relief hole on the spool. 3, the gasket adopts stainless steel leather clip PTFE or flexible graphite winding structure;
4, when the valve is closed, in order to prevent the low temperature medium in the valve chamber due to temperature rise, resulting in abnormal gasification boost, pressure relief structure is arranged on the high pressure side of the gate or valve body;
5, the sealing surface of the valve is surfacing cobalt-based hard alloy, hard alloy deformation at low temperature is small, wear resistance, can maintain good sealing performance.
Due to the output of liquid low-temperature media such as ethylene, liquid oxygen, liquid hydrogen, liquefied natural gas, liquefied petroleum and other products are not only flammable and explosive, but also gasification when heating up. When gasification, the volume expands hundreds of times. Low temperature valve material is very important, the material is not qualified, will cause the shell and sealing surface leakage or leakage; The comprehensive mechanical properties, strength and steel of the parts can not meet the requirements of use or even fracture; Causing a leak in the liquefied natural gas medium and causing an explosion. Therefore, in the process of developing, designing and developing low temperature valves, material treatment is the primary and key issue.