If the vertical multistage centrifugal pump is installed carelessly, it will lead to the failure of installation, which will affect the working performance of the pump in the future. Next, we will analyze the common installation errors and relevant solutions of vertical multistage centrifugal pump.

1. There are many elbows on the inlet pipeline of vertical multistage centrifugal pump

If more elbows are used on the inlet pipeline, it will increase the local flow resistance. Moreover, the elbow shall turn in the vertical direction, and it is not allowed to turn in the horizontal direction to avoid air collection.

2. When the water inlet pipeline of the device is, the horizontal section is horizontal or upward

This will collect air in the water inlet pipe, reduce the vacuum of the water pipe and water pump, reduce the water suction head of the water pump and reduce the water output. The correct approach is: the horizontal section should be slightly skewed towards the water source, should not be horizontal, and should not be tilted upward.

3. The water inlet of multistage centrifugal pump is directly connected with the elbow

This will cause uneven distribution of water flow through the elbow into the impeller. When the diameter of the inlet pipe is larger than that of the water pump inlet, an eccentric reducer shall be installed. The plane part of the eccentric reducer shall be installed above and the inclined part shall be installed below. Otherwise, the air will gather, the water output will be reduced or the water will not be pumped, and there will be impact sound, etc. If the diameter of the inlet pipe is the same as that of the water pump inlet, a straight pipe shall be added between the water pump inlet and the elbow, and the length of the straight pipe shall not be less than 2 ~ 3 times the diameter of the water pipe.

4. The outlet pipe of the multistage centrifugal pump is above the normal water level of the outlet tank

If the water outlet is above the normal water level of the water outlet pool, the pump head is added, but the flow is reduced. If it is necessary for the water outlet to be higher than the water level of the water outlet pool due to terrain conditions, elbows and short pipes shall be installed at the pipe orifice to make the water pipe become siphon type and reduce the height of the water outlet.

5. The water inlet position of the water inlet pipe is incorrect

① The distance between the inlet of the inlet pipe and the bottom and wall of the inlet pool is less than the diameter of the inlet. If there is sediment and other pollutants at the bottom of the pool, when the interval between the water inlet and the bottom of the pool is less than 1.5 times the diameter, it will cause poor water inflow or absorb sediment and sundries during pumping, blocking the water inlet.

② When the water inlet depth of the inlet pipe is not enough, it will cause vortex on the water surface around the inlet pipe, affect the water inlet and reduce the water output. The correct installation method is: the water inlet depth of small and medium-sized water pumps shall not be less than 300 ~ 600mm, and that of large water pumps shall not be less than 600 ~ 1000mm.

6. When setting the bottom valve, the lowest section of the inlet pipe is not vertical

In such a device, the valve cannot be closed by itself, resulting in water leakage. The correct installation method is: for the water inlet pipe with bottom valve, the lowest section should be vertical. If it cannot be installed vertically due to terrain conditions, the included angle between water pipe axis and horizontal plane shall be more than 60 °.

Many factors should be considered in the installation of water pump, among which the more important is the installation of pipeline. Pumps and pipes are often used together. They need to consider and cooperate with each other in order to achieve the best effect.