Cyogenic liquid pump safely

When the cryopump is working normally, you can slowly close the discharge pipe to let the p ressure of the discharge gradually rise to 5mpa. If the low pressure operation is normal, you should always pay attention to whether there is ice on the piston of the pump or other phenomena. . When leakage is found, the nut of the piston rod can be re-tightened. If there is no improvement, the nut of the pump can be unscrewed and re-tightened; Tighten again. The pump has been running for a long time, and the leakage at the piston rod is large and cannot be ruled out. The sealing ring should be replaced.