How to Determine Available System NPSHA for a Pump

[@slengoslengaw8510]

Is NPSH calculated for closed loop systems as well? Everywhere I search it only shows examples for open loop

[@saeidahmadi9323]

Excellent explanation.

[@brandonsanders3095]

How do you measure pump vibration?

[@Varunkm110]

Great I need one session about NACE with API standards.

[@ahmedmohammed9486]

Excuse me! How could you calculate the frictional head without knowing the pipe length

[@tylertinkey3840]

i can go over this with you if you would like

[@sachinkavathekar2259]

How to decide NPSH test is required or not?

[@SahanKolluri]

How velocity and frictional head are calculated can anyone explain in detail?

[@Reubes86]

Wish I knew the formulas

[@moideenyousaf3757]

why add the friction head and elevation head with absolute pressure. absolute suction pressure is the sum of friction head and elevation.

[@ahmedmohammed9486]

I think so Thats why I got confused

[@tylertinkey3840]

@@ahmedmohammed9486 this is an old comment, but I think the friction losses he is talking about is the friction loss from the point where the pressure gauge is installed to the pump suction. This is an extremely small number and is definitely not calculated correctly in this video. There is no way you lose 0.35 ft head in a 1ft section of pipe. In the video, he does exactly what you are saying - he included the friction losses in the suction line twice: once when he read off the suction pressure from the gauge, and another time when he subtracted the total friction loss in the suction line in his formula. The elevation 'hg' he does do correctly. its just the elevation of the pressure gauge itself from the pump suction. Again, this is a very weird way to do this, but he is doing it correctly. He does a very poor job explaining what each term means. He should have video taped himself by the actual pump and pointed to each of the areas so we could understand it more easily. This is the problem with people who just want to memorize formulas to learn things. You need to conceptually understand what the formula is accounting for before you can use it. I applaud you for catching this mistake - it only dawned on me until after I read your comment.

[@jonathankabanga9425]

Thank you. I also think that the velocity head should also be included in the suction head. Please correct if i am wrong

[@processengineer1162]

thank you

[@s.susithara7b10]

Thanks lot

[@glamisfuntopia]

i used to work with him

[@ahmedmohammed9486]

?

[@moideenyousaf3757]

3 INCH PIPE 400 GPM!!!!!!!

[@youseeonlydust]

Useless video. Explain in detail

[@masihtukhi6356]

I don’t know if key details were left out purposely or the video maker was truly stupid. When the pressure at suction was measured, how was it converted to head? How was friction head determined using gpm and pipe diameter? NPSH available was never compared to required. The most childish thing was mentioning at the end “ now you know how to calculate NPSH available”. I think KZbin should delete this video and ban the person who uploaded this video. That will benefit student, seriously.

[@TTGTanner]

Calm down brother. 1 PSI = 2.31 ft of head for water. There’s a simple pipe loss formula, google it. You’ll need to know the roughness of your pipe for that -> look at engineeringtoolbox.com. And yes he never compared NPSH available to NPSH required (from pump). I believe that NPSH available must be greater than NPSH required to avoid cavitation. Someone please correct me if i am wrong

[@Reubes86]

Where can I find the formulas that he used to do all the calculations