The centrifugal pump is used at a temperature of about 80 °C. After the pump is turned on, the pump pressure rises to normal and the outlet pump pressure is normal. The pump pressure drops rapidly in about 10 minutes with noise, vibration, and cavitation. Check whether the sewage station valve is closed.
The material pump material is about 90 degrees, and the gas is easily vaporized. After the pump is turned on, the pump pressure rises to normal. Because the feed amount is small, the pump outlet is small and the pump pressure is normal. The pump pressure drops about 30 minutes, and the cavitation phenomenon occurs with noise vibration. After the occurrence of the phenomenon, we found that there are two cases in which the opening of the outlet valve is not large; the other is that the temperature of the pump inlet and outlet material is significantly higher than the original. The reason for the occurrence of cavitation in these two cases is that the outlet valve opening is not enough or If the outlet valve is not opened or the opening degree is small, the energy obtained from the pump is not sent away in time. The kinetic energy obtained by the material is converted into heat to increase the temperature of the material. When the temperature reaches a certain temperature, the steam is generated in the pump body. Eclipse phenomenon.
After the reasons are clearly analyzed, it is solved. After the pump outlet is connected with a return line and the pump is opened, the reflux valve is properly opened and no cavitation has occurred.
1. Check the centrifugal pump piping and joints for looseness. Turn the centrifugal pump by hand to see if it is flexible;
2. Add bearing lubrication oil to the bearing body and observe that the oil level should be at the center line of the oil mark, and the lubricating oil should be replaced or supplemented in time;
3. Unscrew the water diversion screw of the pump body of the centrifugal pump to infuse the water (or the slurry);
4. Close the gate valve and outlet pressure gauge of the outlet pipe and the imported vacuum gauge;
5. Jog the motor to see if the motor steering is correct;
6. Start the motor. When the centrifugal pump is in normal operation, open the outlet pressure gauge and the inlet vacuum pump, and then display the appropriate pressure, gradually open the gate valve and check the motor load condition;
7. Try to control the flow rate and lift of the centrifugal pump within the range indicated on the sign to ensure that the centrifugal pump operates at the highest efficiency point to obtain the maximum energy saving effect;
