A submersible pump is one of many types of pressure pumps. It is used to pump water from very great depths. It has a screw-type or monoblock design and operates on the principle of a centrifugal pump. It is designed to operate in water and has a wide range of applications in industry and households. A submersible pump is essential, among other things, for extracting water from deep wells. Let’s check which parameters to consider when choosing the right submersible pump.
Energy efficiency and operational reliability
The right submersible pump should be efficient and reliable above all. High performance should go hand in hand with energy efficiency and reliable operation under all conditions. The operating costs of a submersible pump should not be too high. A submersible pump must have a low energy consumption coefficient. It should be operated within its highest-efficiency range. A submersible pump will be energy-efficient if it is properly selected for the type of well, the diameter and depth of the borehole, the depth of the water table, the height of the building, water demand, and the distance between the well and the building. The motor power, which usually ranges from 500W to 1500W, also has a significant impact on pump efficiency. Another important parameter is the thermal rating, meaning the permissible liquid temperature.
Pump flow rate Q and delivery head H
Determining the pump flow-rate parameter involves identifying the operating point. Pump flow rate is expressed in dm3/s or m3/h, meaning the volume of liquid pumped in a given unit of time. Put simply, pump flow rate is the flow rate required to meet the water demand. On the one hand, the pump flow rate must meet the operational requirements of the supplied facility; on the other, it must be adapted to the well’s yield and flow resistance. The pump flow rate must always be lower than the well’s yield.
The liquid delivery head is expressed in metres of liquid column and specifies the pressure the pump must generate, taking into account approximately 20% of linear and local losses. The geometric delivery head is the difference between the highest liquid outlet and the water table. It is best to measure the distance from the water table to the water connection in the building, and then from the connection to the highest outlet point. Add both values together, then add 20% of the geometric delivery head and an additional 20 metres to maintain the correct pressure required at the tap.
