positive displacement,internal gear pump

[Smasem]

dears
may you advice
what is meant by head 400 psi stamped on the internal gear pump name plate ?
and what is effect on the pump if the discharge pressure keep constant on 500 psi?
thanks

 

[LittleInch]

Could mean two things.

1) There is an internal pressure relief valve set at 400 psi which means you won't get to 500 psi.

2) The motor is sized for 400 psi so may be overloaded at 500 psi as the flow will be more or less the same.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[btrueblood]

To go a bit further, it could also mean that you may get away with it, as long as there is never a spike in the outlet pressure due to something like a sudden valve closure. The pump is designed and rated by the manufacturer to a certain pressure limit, with a certain factor of safety. Likely the pump was hydrostatically tested and passed at something like 1.5x the rated pressure (or not), you exceed that at your own risk (i.e. a failure due to excessive case pressure will void the warranty).

 

[JJPellin]

A pump like this would normally be rated in two ways. First is the maximum differential pressure it can produce. This may be based on the mechanical design of the pump or the power of the driver. The pump may also be rated for a maximum operating pressure with an associated hydrotest pressure. This is the pressure limit of the outer casing to contain pressure. The listing on your nameplate of "Head" looks like a differential pressure rating. So, simply telling us that the pump would run with a discharge pressure of 500 psi tells us nothing about the differential pressure. And the head rating of 400 psi tells us nothing about the maximum operating pressure or hydrotest pressure.

Johnny Pellin

 

[FACS]

You can also contact the pump manufacturer to get a clear meaning

 

[smithtasticness]

I'd assume this was the maximum pressure the pump could take, however 400 psi for a gear pump seems quite low to me. It does state head next to it though so it could be that the pump will operate comfortably at higher pressures but the maximum head of the inlet is 400 psi. I'd just ask the manufacturer for clarification.