Why the pump is operating off the curve

[Mous1747]

The pump is operating off the curve (curve is attached) at one point the discharge conditions were about 350 psi and 170 GMP then it was sent out to a shop for repair and now the discharge conditions are 420 psi and 85 GPM.

the pump has 100 HP motor

this situation just came up today so i am still digging into it trying to get some more information but i was hoping to get some thoughts on what to look for?

 

[EdStainless]

It is closer now that it was before. Other than you running against more restriction I don't see the question.
Did the guys that worked on it run any tests? What did they get?
Can you run at another flow ans see what you get for head?
If this is in a well have you adjusted for submergence?

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P.E. Metallurgy, consulting work welcomed

 

[MortenA]

what kinds of "repairs"? If the impellar was replaced or in any other way changed that why.

I reality the pump never operates "off the curve" but the curve can change due to wear etc.

 

[Artisi]

Is the pump running in the correct direction?

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.)

 

[LittleInch]

What is pump suction pressure?

Pump curves give pump differential head.

What is pump impellor diameter?

11 inch is the maximum.

Has this impellor even been skimmed? I.e reduced in diameter?

Like artisi says always check rotation is correct if big changes happen when the pump is removed for maintenence.

Has anything changed on the discharge side?

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