(1) The outlet pressure value of the water ring vacuum pump is normal, stable, without fluctuation, and there is no evacuation phenomenon, indicating that the operation method and process conditions of the water ring vacuum pump are correct.

(2) When the motor is tested alone, the vibration is very small, and the temperature and current are normal, indicating that the motor itself does not have any factors that cause the vibration to exceed the standard.

(3) In order to eliminate the unbalanced quality of the rotating parts of the pump, the asymmetry of the unit line, the poor mechanical strength and rigidity of the parts, and the wear and tear of the bearings and sealing parts, the pump is disassembled according to the conventional method, and the axis of the unit is rebuilt. Correction, check the fixation of the water pipe, check the bearing clearance of the bracket, check whether the shaft is bent, check whether the impeller or balance plate is skewed, etc. After eliminating these reasons, re-tighten the anchor screws and find that the vibration changes little, indicating that the conventional treatment is not complete. Solve the problem of vibration.

(4) The inspection of the foundation of the water ring vacuum pump and its adjacent parts found that:
①A section of pipeline and valve in the horizontal direction of the on-site inlet pipeline vibrates with the equipment. The valve is heavy and most of its mass is supported by the water ring vacuum pump.
②The inlet vent line support has been disconnected and vibrated with the pump.
③The equipment foundation is rubber support, and the equipment support type is flexible support. The rubber support and the pump and motor chassis are only supported by 6 rubber supports, and the contact form is point contact. The rest of the chassis is suspended from the foundation and does not contact the foundation.

Based on the above analysis, it can be seen from the results of the vibration detection of the water ring vacuum pump that the cause of the serious horizontal vibration of the free end of the motor and the free end of the pump is the basic problem.