How to calculate NPIPA & NPIPR for PD pumps

Thread starter jaybikes
Start date Nov 18, 2008
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Pd Pumps

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To calculate NPIPA and NPIPR for positive displacement (PD) oil pumps, understanding the critical role of suction conditions is essential. The discussion highlights the analogy between these parameters and NPSH and NPSHR in centrifugal pumps. A referenced article provides valuable insights and formulas necessary for accurate calculations. Users are encouraged to review the article for detailed testing methodologies related to PD pumps. Properly determining these values is crucial for optimizing pump performance.

Nov 18, 2008

jaybikes

How do I determine NPIPA and NPIPR for PD oil pumps. I understand from limited research that suction condition is critical to the success of each application, but I do not know the formulas.

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Nov 19, 2008

FredGarvin

Science Advisor

Have you taken a look through this article? The parameters you are looking for are analagous to NPSH and NPSHR in centrifs.

http://findarticles.com/p/articles/mi_qa5350/is_/ai_n21301101

Nov 19, 2008

jaybikes

Thanks Fred. Article on testing PD pumps really helped.

Jay

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