Self Priming Pumps Queries (Sanaitary Water Service)

[Tilas]

Hi Guys,

Just wanted to know couple things with self priming pumps.

1. If the pump manufacturer says it is capable of suction lift of 6 Meters , then that means as long distance from highest point of the suction pipe to the surface of liquid plus head losses on the suction piping should be less than 6 meters for the pump to work?
2. I suppose I need to make sure that there is enough NPSH margin at the centerline of the pump impeller also?
3. For power calculation, do I need to add the suction lift (meaning differential head of the pump plus suction lift).
4. Is a foot valve mandatory for self priming pump? Or these pumps can work without foot valves also.

Thank you so much in advance.
Tilas

 

[Artisi]

1. Yes
2.yes
3. Total head for power calculations is measured from supply level to discharge level plus all losses - use lowest level in the sump in the calculation.
4.depends on pump and system design - foot valves on sanitary pumps are /can be a major problem


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.)

 

[Tilas]

Hi Artisi,

Thank you so much for your response.

Regards,
Tilas