Structural features of cryopumps

Vertical structure: suitable for burying in the ground, it will not be affected by the hot air of the motor, air temperature and sunshine, etc., and it is easy to keep cold; it can reduce the suction height of the pump, increase the filling head, and improve the effective NPSH; the vertical structure also It is beneficial to exhaust air, so that the suspension shaft has sufficient height to facilitate the arrangement of the shaft sealing device, so the pump is also called a vertical barrel pump. Symmetrical structure: The overall structure of the pump strives to be symmetrically arranged so that it can deform uniformly in the cold state. The cold head generally adopts a two-stage mechanism, the first stage reaches 80K, and the second stage reaches a temperature of 10K. Double-layer shell: In order to keep cold and facilitate the transportation of dangerous media, it is usually made into a double-layer shell. The inner shell is subjected to pump pressure, and the suction pressure is between the inner shell and the outer shell, which can appropriately reduce the strength requirements of the inner shell. The outer shell needs to be made into a vacuum interlayer, which has achieved the effect of heat insulation.