Several Methods of Controlling Water Flow of Submersible Pump

For the use of submersible pumps, we are mainly draining water, so I believe that many of the control of water output and water flow are not understood. Next, I will explain the various adjustment methods of water flow control of submersible pumps.
1. Variable speed adjustment. Changing the speed of the submersible pump can change the performance of the pump, thereby changing the working point of the pump. This method is called variable speed adjustment.
2. Adjustable diameter adjustment. After the impeller is turned, the performance of the water pump will change according to a certain rule, so that the operating point of the water pump will change. We call the method of turning the impeller to change the working condition of the pump, which is called the variable diameter adjustment.
3. Variable angle adjustment. Changing the installation angle of the blades can change the performance of the pump, so as to achieve the purpose of changing the operating point of the submersible pump. This way of changing the operating point is called variable angle adjustment of the pump.
4. Throttle adjustment. For the water pump device with gate valve installed in the outlet pipeline, if the gate valve is closed for a small amount, local resistance is increased in the pipeline, and the pipeline characteristic curve becomes steep, and its operating point moves to the upper left along the Q-H curve of the pump. The smaller the gate valve is closed, the greater the increased resistance and the smaller the flow rate. This method of changing the operating point of the pump by closing the gate valve is called throttling adjustment or variable valve adjustment.

When the gate valve is closed, the local head loss of the pipeline increases, the characteristic curve of the pipeline system moves to the upper left, and the pump operating point also moves to the upper left. The smaller the gate valve is closed, the greater the local head loss and the smaller the flow rate. It can be seen that throttling adjustment not only increases the local head loss, but also reduces the water output, which is very uneconomical. However, due to its simplicity and ease of use, it is widely used in small water pump installations and water pump performance tests.