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Low temperature valves include low temperature ball valve, low temperature gate valve, low temperature globe valve, low temperature safety valve, low temperature check valve, low temperature butterfly valve, low temperature needle valve, low temperature throttle valve, low temperature pressure reducing valve, etc., suitable for medium temperature of -40℃ ~ -196℃ valve.

Cause of leakage of low temperature valve:

There are two main cases of leakage of low temperature valve, one is internal leakage; The second is leakage. 1. The main reason for the leakage of the valve is that the sealing pair is deformed at low temperature. When the medium temperature drops to the material phase change caused by volume change, so that the original grinding precision of the sealing surface warping deformation resulting in poor low temperature seal. 2, the leakage of the valve: one is the valve and pipeline using flange connection, due to the connection pad, connecting bolts, and connecting parts in low temperature between the material contraction is not synchronized relaxation and lead to leakage. It is mainly used in ethylene, liquefied natural gas plant, natural gas LPG LNG storage tank, receiving base and satellite station, air separation equipment, petrochemical tail gas separation equipment, low temperature storage tank of liquid oxygen, liquid nitrogen, liquid argon and carbon dioxide, tank truck, pressure swing adsorption oxygen production device, etc. Therefore, the connection mode of valve body and pipeline can be changed from flange connection to welding structure to avoid low temperature leakage. The second is the leakage of stem and packing.

Low temperature valve output liquid low temperature medium such as ethylene, liquid oxygen, liquid hydrogen, liquefied natural gas, liquefied petroleum products, not only flammable and explosive, but also in heating to gasification, gasification, volume expansion hundreds of times.