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old pump suction pressure
3

old pump suction pressure

old pump suction pressure

(OP)
Hi, if i have an old pump with no datasheet, and i dont know its suction pressure, how can i find it. I want to check how much maximum suction pressure it can provide or how much below the pump suction level, my tank can be. Thanks a lot.

RE: old pump suction pressure

Do you know the pump manufacturer? Do you know the pump model? Do you know if the pump is a centrifugal pump or a positive displacement pump? Do an on-line search or contact the pump manufacturer. If you don't know any of these things, post a picture and maybe we can identify it.

Johnny Pellin

RE: old pump suction pressure

You can always test for it. Connect the pump to source, set the output to equal your maximum expected flow, throttle the suction until you see a rapid drop off in motor amps (cavitation begins). This is your minimum suction pressures. Add 25% for safety and send it.

RE: old pump suction pressure

The way you talk it sounds like a piston type pump??

You will probably be looking at a maximum lift of about 7m providing your fluid has a very low vapour pressure.

You have given us about 3% of the required information....

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

RE: old pump suction pressure

IMO, ask your technician or the local vendor to verify the pump maker and model before any DIY action. I believe as a minimum, you want to know some basic pump conditions of the minimum/normal flow operation before running a pump test.

RE: old pump suction pressure

(OP)
@JJpellin .. dont know the manufacturer, its an old pump, we wanted to check if we could use it but didnt work.. may be it needs priming..

@TugboatEng .. could i bug you for more details.. can i connect a pressure gauge near the pump suction and run it and read off it to check the suction pressure.. ?

RE: old pump suction pressure

Tried my crystal ball without success, plus you have already been asked to post a photo, you are currently wasting everyone's time asking non answerable questions. Old pump without a name is completely useless.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: old pump suction pressure

Ysin,

Can we bug you for more details.

Like
Pump type? Centrifugal or piston or ??
Size / power ?
Picture?
Any details at all written on the pump?
How old?

If you need to prime the pump to work can you do it.

Why are you trying to use a pump you seem to know nothing about??

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

RE: old pump suction pressure

(OP)
Hi.. It's a centrifugal pump.. Sorry for wasting your time.. Looks like the attached pic.. But plates are missing so dont know the details.. I thought I could measure how much suction pressure it Could generate by using a pressure gauge.. Anyway.. I don't want to waste anyone's time so don't bother to answer.. I ll just search on Google.. Thanks for the inputs everyone

RE: old pump suction pressure

Well that's a start. If you get it primed then it should go down to about 6 to 7 m of lift based on water at ambient temperature.

Yes stick in a pressure guage on the inlet line but make sure it's one which registers negative pressure compared to atmospheric pressure

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

RE: old pump suction pressure

Seems your joking, that's a brand new unused Grundfos multi-stage pump, probably capable of around 7 maybe 8 metres suction lift.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: old pump suction pressure

Still meaningless other than its probably a Grundfos, and doesn't change the prior comment, probably capable of 7 maybe maximum 8 metre suction lift depending on the condition of the pump internals.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: old pump suction pressure

What is the liquid you're pumping at what temperature?

Also how are you priming the pump? Most centrifugal pumps won't self prime

And that's one of the more errr interesting electrical terminal covers. Please tell me there's something underneath what looks like tin foil

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

RE: old pump suction pressure

(OP)
pumping water at around 28 degrees Celsius... i was trying to find this out for a friend... and i sent him two videos from youtube on how to prime.. which recommended installing a standpipe in the suction line and filling it with water until water starts to drip out of another opening on the pump.. called the fill plug... but after i sent him the video.. he told me they decided to use a bigger pump and everything is fine now... i am attaching the picture from the video for priming.. thanks a lot guys...

RE: old pump suction pressure





It is a multistage centrifugal pumps . This pump type are standard, to feed boilers from condensate return systems . Look for a similar pump brochure and compare stages, suction diameter line and find the equivalent data; it will no be the same, but will be close


horacio

https://www.linkedin.com/company/lagotuy/

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