NPSH Required for VTP 1

[jamaican]

I am asking anyone out there who knows and can assist me with the issue of NPSH required for a vertical turbine pump. I know how it is calculated and all that. What I need to know is if the requirement changes with each additional stage of the pump. Is it that the requirement given for one stage is the same for five stages, if not what is the ratio of change in the requirement.

 

[bimr]

You only have to be concerned about the NPSH requirements for the 1st stage.

The first stage can be lowered (along with the sump depth) to provide the correct NPSH. The first stage can also be lowered into the water as well if one desired to avoid priming issues.

 

[jamaican]

Thanks bimr for the response, I have being in the pump business almost 2 years on learning it and loving it, thanks again.

 

[Artisi]

It is very rare for NPSHa to be an issue with vertical turbine pumps installed in a sump / pit as you normally have 1 atms available plus any submergence.

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.)