1.Nuclear magnetic resonance (cryogenic superconductivity) field
Magnetic resonance imaging (MRI) uses the cryogenic superconducting magnet technology requires cooling liquid helium, according to the statistics, nuclear magnetic resonance (NMR) imaging accounted for 34% of the world’s dosage of helium, one of the biggest end use industry. Although demand for magnetic resonance imaging in developed countries is declining, but demand is still strong growth in developing countries, so as to keep the strong demand of liquid helium.
2.Refrigeration (home appliances) field
Helium gas is mainly used for detecting the leakage of condenser, evaporator and pipeline system.
3.Semiconductor, fiber field
Helium is mainly used for protecting gas of germanium and silicon crystal growing in semiconductor industry. Cooling and protective atmosphere gas in fiber prefabrication and fiber drawing processes.
4.Welding shielding gas
Usage: When some metals are heated or melted, an inert atmosphere must be used to prevent them from reacting with oxygen and nitrogen in the atmosphere. A lot of helium is consumed in metal welding. In inert gas shielded tungsten arc welding (TIG), unmelted tungsten electricity, searing metal filler and welding areas are protected by a continuous mixture of helium or helium-argon. The gas mixture used in the welding can be prepared in different proportions by helium and argon. Depending on the welding process, the welding wire and the difference of base material welded, the mixture can be composed differently, and the helium content in the helium-argon mixture is usually 15-70%.
5.Cryogenic engineering
Usage: Due to the chemical inertness of helium and extremely low liquefaction point, it is at all except for extremely cryogenic is close to the ideal gas behavior, and the unit mass of high heat capacity, low viscosity and high thermal conductivity characteristics, so the helium is typically used as the working medium of closed cycle cryogenic refrigerator, cryogenic superconducting magnet in major national science and engineering, and superconducting cavity cooling medium, and the college scientific research experiments, etc
6.aerospace
Usage: In rocket and space vehicle fuel systems, helium is used to clean cryogenic fuel and oxidize tanks, as well as pressurized cryogenic tank liquid surface space to provide pressure for direct delivery of liquid hydrogen and liquid oxygen or only to provide net positive suction pressure to infusion pumps. Helium is often used as a working medium in pneumatic control systems.
7.Automobile manufacturing field
Usage: Helium is used in automobile airbag, air tightness detection of aluminum alloy wheel hub, air conditioning evaporator, compressor and condenser, and application of helium in laser welding of automobile frame.
8.Other field
Physiological and medical treatment, nuclear reactor, electric light source, metallurgy and metal processing technology, analysis and test of carrier gas, etc. This part of gas is generally not recycled.
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