Dilute oil metallurgy requires high vacuum conditions. Therefore, complete sets of high vacuum unit equipped with mechanical pumps and diffusion pumps are often used. Vacuum can be pumped up to 10-6 Pa in series with mechanical pumps and booster pumps. In order to further improve the vacuum, needle adsorbents or cold traps can be placed in the working system to absorb or condense the gas that has not been pumped out. In order to improve the pumping capacity in a certain vacuum range, a first-stage mechanical booster pump is sometimes added in series or parallel with the unit.
In high vacuum units, mechanical pumps can reduce the air pressure from an atmospheric pressure, called the front pump; diffusion pumps can only pump from a lower pressure to a lower pressure. They are called secondary pumps. The pressure at which the secondary pump starts to work is called the preparatory vacuum or the front vacuum. The optimum pumping speed of each vacuum pump corresponds to a certain inlet pressure. Therefore, the optimum vacuum benefit can only be obtained by reasonably matching Jun vacuum unit. An unreasonable configuration will not only cause waste, but also cause the vacuum degree of its air system to fall short of the expected requirements.
没有评论:
发表评论