Daily Question 10.28: When shutting down the pump urgently, close the outlet valve first, then stop the motor
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10.28 When shutting down the pump urgently, close the outlet valve first, then stop the motor ( )
That’s right; first reduce the opening degree of the outlet valve, then turn off the motor.
It should be correct; it seems to be out of fear of backflow
When shutting down the pump urgently, close the outlet valve first, then stop the motor (X)
When shutting down the pump urgently, close the outlet valve first, then stop the motor (X)
Yes, to prevent backflow of the medium from causing the pump to rotate in reverse and damaging its components
10.28 When shutting down the pump urgently, close the outlet valve first and then stop the motor (incorrect). This is the proper sequence for normal shutdown; in an emergency, the motor can be stopped directly, and it’s best to do this remotely. If there is a leak or fire, operators should not approach the area
The answer to this question is incorrect. It depends on the type of pump. For centrifugal pumps, it is usually sufficient to close the outlet valve first before shutting down the pump, as closing this valve reduces the flow rate and current, thereby lowering the load on the pump. In contrast, closing the outlet valve first in case of positive displacement pumps can cause overloading of the pump, leading to damage to the pump itself or its packing, and even burning out the motor. Some positive displacement pumps are equipped with check valves or return valves, which allow the outlet valve to be gradually closed and the return valve to be opened before shutting down the pump, making the process easier.
A check valve is now installed at the pump outlet; in the event of an emergency shutdown, the motor should be stopped first, followed by closing the outlet
When shutting down the pump urgently, it is correct to close the outlet first and then stop the motor.