Why are the inlet and outlet valves of a screw pump fully open when it is started?
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Our factory’s desalination water pumps used to be multi-stage screw pumps. When starting the pumps, the outlets were always kept closed, and they were opened only after the pumps started operating. Has this been the wrong approach all along? Then, may I ask about the normal status of the inlet and outlet of the standby screw pump? Thank you
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I’m familiar with piston pumps and reciprocating pumps. What I’m referring to here is a screw pump used for feeding water into a catalytic external heat-extraction steam drum – it’s a multi-stage compression type. However, it isn’t very effective; the outlet pressure never reaches the required level. I haven’t tried running the pump with the outlet open. I’d like some advice on this~
I’ve learned something~~~~~ Thank you!
A screw pump is a positive-displacement pump that transports fluid by increasing the pressure in a sealed volume through the rotation of screws; therefore, to prevent the pressure from rising too rapidly, it must be started with the inlet and outlet open.
The outlet valve of a positive displacement pump should not be closed, otherwise the pressure will continue to rise; the outlet valve can be closed when starting a centrifugal pump
If the outlet is not opened, starting the pump will cause an instantaneous excessive pressure in the pump’s outlet section, posing a significant risk to both the pipelines and the pump; therefore, the outlet valve must be opened before starting the pump!
The outlet valve of a positive displacement pump should not be closed, otherwise the pressure will continue to rise
Multi-stage screw pump? Is there any manufacturer information? After all, the operating requirements specified in the device manual are the most fundamental
Before starting a positive-displacement pump, the inlet and outlet valves must be opened to prevent pressure buildup.