The principle of selecting a water pump is to adapt to changes in flow rate while meeting the maximum drainage flow rate, achieving low investment, low power consumption, low operating costs, safe and reliable operation, and convenient maintenance and management.
The head of a sewage pump station is generally small. When the sewage flow is not large and the pump room is buried deep, a vertical centrifugal sewage pump can be selected; When the burial depth of the pump room is not large, a horizontal centrifugal sewage pump can be selected; When the flow rate is large, a mixed flow pump or an axial flow pump can be selected. At present, submersible sewage pumps have been applied in drainage engineering. The stainless steel submersible sewage pump combines the water pump and electric motor to work underwater together. It has a simple structure, easy installation, and pump room structure
Due to its simple structure and low cost of pumping stations, sewage submersible pumps should be given priority when selecting water pumps.
The water level in the collection tank often changes, causing changes in the head of the water pump during operation. Therefore, the selected water pump should operate in the high-efficiency section within the range of water level changes in the collection tank. When two or more sewage centrifugal pumps are selected for parallel operation in a sewage pumping station, it should be ensured that the pumps not only work in the high-efficiency section when running in parallel, but also in the high-efficiency section when running as a single pump. The same model of water pump should be selected, with a minimum of 2 units and no more than 8 units. When the flow rate changes significantly, different specifications of water pumps can be configured, but not more than two, or variable frequency speed control devices can be used, or water pumps with adjustable blade installation angles can be used.
The sewage pump station should be equipped with units. When the number of working pumps is not more than 4, the standby unit should be 1; When the number of working pumps is not less than 5, the standby unit should be 2; When there are 2 backup units in the submersible pump station, 1 can be used for on-site backup and 1 can be used for inventory backup.
The flow rate of sewage pumping stations gradually increases with the phased construction of the drainage system, and this factor must be considered in the design.
