Calculation of positive displacement pump
Calculation of positive displacement pump
(OP)
Hi
I'm doing a calculation of a positive displacement pump and I have a question.
At suction flange the pressure is 1 kgf/cm2 g (considering all suction losses).
Considering all downstream pressures losses, the required discharge pressure is 6 kgf/cm2 g.
Should I calculate required design pressure for this pump like centrifugal pumps (required discharge pressure less suction flange the pressure) resulting 5 kgfc/cm2 g, or should I consider 6 kgf/cm2 g as pump discharge pressure?
Tks
I'm doing a calculation of a positive displacement pump and I have a question.
At suction flange the pressure is 1 kgf/cm2 g (considering all suction losses).
Considering all downstream pressures losses, the required discharge pressure is 6 kgf/cm2 g.
Should I calculate required design pressure for this pump like centrifugal pumps (required discharge pressure less suction flange the pressure) resulting 5 kgfc/cm2 g, or should I consider 6 kgf/cm2 g as pump discharge pressure?
Tks





RE: Calculation of positive displacement pump
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Calculation of positive displacement pump
RE: Calculation of positive displacement pump
The design pump of selected pump from pump manufacturer is 7.5 barg, then in this case it's ok no matter considered calculation. But I would like to know if the design pressure were 5,5 kgf/cm2g, for example, it'd be ok or I'd have problems.
Take care
RE: Calculation of positive displacement pump
Please tell me you have a full flow pump recircualtion line set somewhere between 6 and 7.5 barg. In reality your gap between 6 and 7.5 is probably too small and your re-circ valve will either leak or not protect your pump or your downstream pipeline. What is your maximum inlet pressure? the pump will just pump the flow so could add 5 barg to whatever your inlet pressure is.
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Calculation of positive displacement pump
RE: Calculation of positive displacement pump