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CENTRIFUGAL PUMPS AND VFD pumps

CENTRIFUGAL PUMPS AND VFD pumps

CENTRIFUGAL PUMPS AND VFD pumps

(OP)
Hi friends I am working in oil -chemical industry. Actually we r using 2 centrifugal pumps of 500 m3/ hr capacity each. Its discharge pressure goes up to 8 bar before the filter. Due to 8 bar we often have problem of leak in filter cover gasket.pressure releif valve lifting. So we throttle t discharge valves to reduce pressure to 4 bar and run 2 pumps. I THINK if i change this centrifugal to VFD pumps its possible to use one pump only also is it efficiency in terms of capacity and electrical consumption. Thanks

RE: CENTRIFUGAL PUMPS AND VFD pumps

So check the pump performance curves to see if there is a reduced speed at which you can get 900-1000m3/hr at 4barg discharge..

A better solution would be fix this gasket leakage / PSV lifting problem at the filter. That would be easier than to fit VFD to these 2 pumps.

RE: CENTRIFUGAL PUMPS AND VFD pumps

IYYAPPA,

Your post doesn't make sense. If you throttle the pump to 4 bar then your flow also falls to ??. Adding a second pump also presumably throttled to 4 bar won't add any flow.

First off work out what pressure does your downstream system need to flow at whatever flow you want.

Only then can you start fiddling with the pumps, but it sounds like something isn't right if your filter leaks and the pressure relief valve lifts (!)

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: CENTRIFUGAL PUMPS AND VFD pumps

It seems that the VFD pumps could be an alternative to improve your existing pump with pressure control valve system. Other alternatives can be: upgrading filter with better gasket and PSV, replacing pumps with low head and high flow rate, etc. The final solution can be based on what's the availability of the operation budget.

RE: CENTRIFUGAL PUMPS AND VFD pumps

Depending on the NPSHA, you might consider moving the filter to the suction side of the pump.

I used to count sand. Now I don't count at all.

RE: CENTRIFUGAL PUMPS AND VFD pumps

VFD isn't for the pump, it's for the motor.

A centrifugal pump can have a VFD motor on it so I'm confused what you are asking.

Charlie
www.facsco.com

RE: CENTRIFUGAL PUMPS AND VFD pumps

Sounds like you need a bigger filter that has less resistance at the flow rate you want to use. Check the specs on the filter.

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