What are the precautions for starting a shielded pump?
Thread Content
Why is it necessary to open a little of the outlet before starting the shielded pump? What else should be considered when starting a shielded pump?
Opening the outlet valve slightly before startup is mainly to exhaust air. There are many user manuals for canned motor pumps provided by manufacturers on the Internet; when starting the pump for the first time, it is necessary to use the \"pulse start\" function to determine the direction of rotation. At other times, one should make sure to slightly open the outlet valve to fill the pump, and use multiple pulse starts followed by a period of inactivity to release air from the system.
For ordinary shielded pumps, the following points should be confirmed before starting: 1. Perform exhaust operation. First, open the inlet valve fully and the outlet valve slightly, allowing the liquid to fill the pump interior and expelling the gas from within the pump through the outlet. 2. Pulse exhaust: Pulse the pump to start it for 3–5 seconds, thereby expelling the gas remaining inside the pump through the outlet. 3. Check the steering – Be sure to check the steering when starting. If it reverses, correct the three-phase power supply wiring. (Invert the situation; the outlet pressure is only 50–70% of that under normal operation.) 4. Adjust the flow rate and pressure to the rated operating point.
A shielded pump is essentially a centrifugal pump, the difference lying only in its sealing mechanism. It should be similar to starting a centrifugal pump