1. What are the main performance parameters of the pump?
Mainly include flow, head, NPSH, speed, power, and efficiency, etc.
2. What is the reason for the excessive power consumption of the pump?
1) The total head does not match the head of the pump;
2) The density and viscosity of the medium are inconsistent with the original design;
3) The pump shaft is inconsistent or bent with the axis of the prime mover;
4) There is friction between the rotating part and the fixed part;
5) The impeller ring is worn;
6) Improper installation of seal or mechanical seal.
3. How to prevent evacuation and cavitation during operation?
Evacuation: There is gas and liquid in the pump, the pump cannot work, and the flow and pressure tend to zero.
Cavitation: It occurs in the pump during operation. It comes from the medium in the pump. The flow and pressure change and drop, resulting in hydraulic shock.
Generally, pump evacuation refers to a kind of cavitation phenomenon that occurs in the pump. Due to the leakage of the installation technology pipeline, evacuation caused by the inhalation of gas is rare, and most of them are caused by changes in operation and process.
In the process of operation, we should start with stable process operating conditions. The lower limit should be taken for the operating temperature and the lower limit for the pressure. In order to avoid or control the occurrence of cavitation, the flow rate of the pump should be moderate during operation, and the occurrence of large pressure and temperature should be minimized. The change. The retention of gas should be prevented in the pump suction line, and the backup pump inlet should be closed when the inlet pressure is negative.