What do the QHN of water pumps stand for?

q represents the flow rate of the water pump, h represents the head of the water pump, and n represents the power of the water pump.

When the pump is working, the liquid at the inlet of the impeller will generate vapor under a certain vacuum pressure. The vaporized bubbles will erode the impeller and other metal surfaces under the impact of the liquid particles, thereby destroying the impeller, etc. For metal, the vacuum pressure at this time is called the vaporization pressure, and the NPSH is the excess energy exceeding the vaporization pressure per unit weight of the liquid at the pump suction inlet. The unit is marked in meters, using (NPSH)r.

Precautions for using water pumps

If the water pump has any minor faults, remember not to let it work. If the packing on the water pump shaft is worn out, it must be added in time. If the water pump continues to be used, air leakage will occur. The direct impact of this is that the energy consumption of the motor will increase and the impeller will be damaged.

When the water pump bottom valve leaks, some people will fill the water pump inlet pipe with dry soil and flush the bottom valve with water. This approach is really not advisable. Because when dry soil is put into the water inlet pipe when the water pump starts to work, the dry soil will enter the pump, which will damage the water pump impeller and bearings, which shortens the service life of the water pump. When the bottom valve leaks, it must be repaired. If it is serious, it needs to be replaced with a new one.