1. Pre start inspection of multi-stage centrifugal pump

Does the name, model, main performance, and quantity of lubricating oil meet the requirements of the technical documents; Whether the bearing lubrication system, sealing system, and cooling system are intact, and whether the oil and water circuits of the bearings are unobstructed;

Rotate the rotor of the rotary pump 1-2 times and check for any friction or jamming of the rotor;

Are there any debris near the coupling or belt protection device that hinders rotation;

Are the foundation anchor bolts of the pump, bearing seat, and motor loose;

The valves or accessories of the pump working system should be in the position with the minimum load during pump operation, and the outlet regulating valve should be closed;

Start the multi-stage centrifugal pump and check if the impeller direction is consistent with the design direction. If not, the impeller must be stopped and the motor wiring adjusted before restarting.

2. Multi stage centrifugal pump water filling

Before starting the water pump, the pump casing and suction pipe must be filled with water first, because in the presence of air, the multi-stage centrifugal pump cannot form and maintain a vacuum in the suction system.

3. Multi stage centrifugal pump warm pump

Pumps that transport high-temperature liquids, such as boiler feedwater pumps in power plants, must be warmed up before starting multi-stage centrifugal pumps. This is because when the feed pump is started, high-temperature feed water flows through the pump, causing the temperature of the pump body to quickly rise from room temperature to 100-200 ℃. This can cause temperature differences between the inside and outside of the pump and between various components. Without sufficient heat transfer time and appropriate measures to control temperature rise, uneven expansion of the pump can occur, resulting in deformation, wear, vibration, and bearing holding accidents of various parts of the pump body.