Hydraulic Submersible Pump

[Muon1]

Hi All,

Can some please give me some advice on a hydraulic submersible pump. My knowledge of pumps is quite limited.

I'm going to be using the pump as part of a jet washing system that will be used to clean the dirt from the walls of a large concrete reservoir. A nozzle will be attached to the discharge side of the pump. The pump will be operating at a depth of 10 meters (1bar). The pump will be using the surrounding reservoir water as the supply.

This is were I'm getting a bit stuck. How is the total head calculated for a submersible pump?

Thanks
Mark.

 

[bimr]

Spray washers for concrete probably need somewhere around 1500 psi to clean concrete. You are not going to get that with a submersible pump.

You have 10 meters of suction head (32.8 ft). The required pressure at the spray washer + pipe friction headloss minus 10 meters of suction head equals the Total Pump Head Required

 

[zdas04]

There are many PD hydraulic submersible pumps that can easily reach very high pressure. These are reciprocating plunger pumps (not centrifugal or other dynamic pumps). They generally fail due to inadequate lubrication, not caviatation. With this kind of pump it is common to talk in discharge pressure, not total head. Reciprocating plunger pumps cannot "suck" and they require some amount of positive pressure at the suction, but the amount required is a function of required flow rate, not required discharge pressure. For most high-capacity industrial power washer applications you need less than 1/2 bar suction pressure. Applications I've spec'd would work well with your 1 bar of suction pressure going into a couple of thousand psi of discharge pressure unless the required flow rate were very high.

David Simpson, PE
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist

 

[DubMac]

Tell us a little more about the size of this reservoir, what you are cleaning off of it, and just how clean you need it.

The experts above are absolutely correct in needing a reciprocating pump if these walls need to be absolutely clean; as clean as say, if you were power-washing your driveway.

On the other hand, if you were just trying to clean large clods of mud off of these walls, and the square footage was really large......say like cleaning a large mud pit on a drilling rig....then you would benefit from having the volume of a centrifugal. You can get a really nice stream of water from a submersible with a good nozzle on the end of a hose.

What you need to look at in either case, especially the centrifugal, would be the pump curve. Do you have that, and can you share?