Many users don't understand the importance of starting a corrosion-resistant self-priming pump and shutting it down after use.

I. Precautions for Starting a Self-Priming Pump

1. Confirm that the suction valve is fully open and the discharge valve is closed or slightly open. If there is a minimum flow line, fully close the discharge valve and fully open the minimum flow valve.

2. Close the check valve in the self-priming pump's outlet line to ensure the minimum flow rate.

3. Start the self-priming pump motor and allow the pump rotor to reach operating speed.

4. Slowly open the outlet valve until the pump's outlet pressure and flow rate reach the specified values. While opening the outlet valve, check the motor current to avoid motor overload. Check the pump for normal vibration, any unusual sounds from the pump body and motor, and any changes in outlet pressure. If the self-priming pump has any unusual leaks, identify the cause and address them.

5. After the self-priming pump is operational, check the pump's outlet pressure, outlet flow rate, motor current, and bearing and seal temperatures.

2. Precautions for Shutting Down a Self-Priming Pump

1. Disconnect the power supply to the self-priming pump, stop the pump, close the outlet valve, and slowly reduce the discharge valve until the flow rate reaches the minimum.

2. If the self-priming pump has a minimum flow bypass line, close the discharge valve with the bypass valve fully open, then disconnect the power supply and stop the pump.

3. When inspecting and shutting down the self-priming pump (to cool it down), first close the nitrogen inlet valve of the dry gas seal system to depressurize the seal chamber. Then, completely drain the liquid in the pump and the cooling water in the cooling system. Reduce the pressure in the pump body to zero, purge any remaining material, close all valves, and disconnect the power to the substation.