With the wide use and continuous emergence of new technologies, new processes and new materials, vacuum technology is more and more used in metallurgical industry, and its benefits are more and more significant.
Vacuum technology is widely used in vacuum metallurgy, such as vacuum distillation, degassing, sintering, heat treatment and so on. Each operation of vacuum metallurgy needs to meet a certain degree of vacuum, and different operations have different requirements for the degree of vacuum.
Now a variety of pumps have been produced. They are constructed according to different pumping principles, have different characteristics, reach different starting and stopping pressures, and are also suitable for operation under a certain range of pressures.
Because of the different pressure of each pump, when the working pressure is low, two or more pumps should be combined to meet the needs.
What is vacuum metallurgy
Vacuum metallurgy is a metallurgical method for smelting and processing metals and alloys under or far below atmospheric pressure. The important role of vacuum in metallurgical process is as follows:
(1) to create favorable chemical thermodynamics and kinetic conditions for the metallurgical reaction with gaseous products, so that some metallurgical processes which are difficult to be carried out under atmospheric pressure can be realized under vacuum;
(2) reduce the solubility of gas impurities and volatile impurities in metals, and correspondingly reduce their content in metals;
(3) reduce the temperature required for volatilization of metals or impurities, and improve the separation coefficient between metals and impurities (see vacuum refining);
(4) reduce or avoid the effect of metal or other reactants on the air, and avoid the pollution of metal or alloy by gaseous impurities. Vacuum metallurgy is mainly used in vacuum separation, vacuum reduction, vacuum refining, vacuum casting, heat treatment, vacuum coating and so on.
The gases produced in vacuum metallurgy may contain different substances, such as dust, fine metal particles, water vapor, volatile organic compounds, harmful gases, etc. appropriate measures need to be added in the pump or pipeline system to ensure the smooth pumping, good operation, long service life and no impact on the environment.
Vacuum metallurgy is a metallurgical operation under the condition of lower than standard atmospheric pressure. It can realize the metallurgical process that can not be carried out in the atmosphere, prevent metal oxidation, separate substances with different boiling points, remove gas or impurities in the metal, enhance the deoxidization ability of carbon in the metal, and improve the quality of metal and alloy. Vacuum metallurgy is generally used for smelting, refining, casting and heat treatment of metals. With the rapid development of cutting-edge science and technology, vacuum metallurgy is increasingly widely used in the smelting of rare metals, steels and special alloys.