The shaft of the vacuum pump keeps bending

The water ring vacuum pump is directly connected to a DN400 water pipeline, and no steam-water separator or valve is installed at its exhaust port. 2 to 3 months after the new pump was installed and put into use, the shaft bent and the impeller wore out. It worked normally when first installed, but the packing ring started to fly out on its own. After being parked for a month, before restarting it, the pump shaft could be rotated freely; however, 1 minute after startup, the impeller got stuck and the shaft bent.

In one and a half years, 4 different water ring vacuum pumps have been damaged. There was once a mechanic who made slight modifications to the imported pipelines, and as a result shaft bending no longer occurred. However, the original water pump room had been demolished, and no one in the company knew how the imported pipelines had been modified

This vacuum pump was damaged due to the entry of large amounts of liquid. What the technician did was likely to install a valve on the inlet pipe of the vacuum pump, and also insert the inlet pipe of the vacuum pump into a DN400 pipe, adding a elbow inside with its direction aligned with the flow direction of the liquid.

If a vacuum pump is used to lift water, a ball valve should be installed at its suction port, and there should also be a valve on the 400-series pipeline. Start the vacuum pump first. Open the intake valve, open the valve on the 400 pipeline. When water is flowing through the exhaust pipeline of the vacuum pump (or it can be determined whether water has reached there by listening to the sound coming from the pipeline), turn off the vacuum pump, close the suction valve, and then close the valve on the 400 pipeline that is connected to the vacuum pump. Then start the water pump. That will do. We have been using vacuum pumps to lift water here for three years now, and the vacuum pumps have not broken down at all. The main reason for the problem you mentioned is probably that no suction valve is installed on the vacuum pump, after the water is lifted up. When starting the water pump. Some water entered the vacuum pump and flowed back.

There are likely issues with the installation and operation of the vacuum pump.

If it’s not due to installation or maintenance, could it be caused by excessive operational load?

Can a water ring vacuum pump also be used to lift water? During parking, the engine should be turned over regularly. The liquid level in the water ring vacuum pump chamber must not exceed the limit.