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.

Common installation errors of vertical multistage centrifugal pump:

1. There are many elbows on the inlet pipeline of vertical multistage centrifugal pump. If there are many elbows on the inlet pipeline, some water flow resistance will be added. Moreover, the elbow shall turn in a straight direction, and it is not allowed to turn in a horizontal direction to avoid air collection. 2. When installing the water inlet pipeline, the horizontal section is horizontal or upward, which 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, which will make the water flow unevenly dispersed when entering the impeller through the elbow. When the diameter of the water inlet pipe is larger than the water inlet of the pump, a bias reducing pipe shall be installed. Some of the flat surfaces of the migraine reducer should be installed on the top, and some of the inclined surfaces should be installed on the bottom. Otherwise, the air will be collected, 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 water inlet pipe and the water inlet of the pump is at the same level, a straight pipe shall be added between the water inlet of the pump 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 water outlet of the multistage centrifugal pump is above the normal water level of the water outlet tank. If the water outlet is above the normal water level of the water outlet tank, although the pump head is added, 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 topographic 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 of the water inlet pipe is in the wrong direction：
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 water inlet pipe is not straight. 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 bottom section is best straight. If the installation cannot be straightened due to terrain conditions, the included angle between the water pipe axis and the horizontal plane shall be more than 60 °.