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i have a problem

i have a problem

i have a problem

(OP)
we have 4 wothington pumps 8ln21  700m3/h, they where used for pumping crude oil. we are using them for pumping sea water, we dont have pressure problems, but we need more flow,we are asking ,if we change their impeller can increase our flow??if yes i would like to know from where i will buy these impellers, or who can make them. our pumps are connected with 500 hp engines.@1700rpm. before these pumps where connected with eletric motors 286kw ,thanks in advance.

RE: i have a problem

Assume you have already run the pumps at 1700RPM, right?
How much more flow do you want 1% or 100%

RE: i have a problem

You may be running these units at 32% over power load capacity right now, assuming you are drawing 500 HP and they were originally designed for 286 kW, and adding more flow may result in "pressure problems" amongst others, such as general power overload.  Running water will increase required power by about 15 to 20% over the same oil flowrate capacity too.  

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying."  Tony Hayward CEO BP
"Being GREEN isn't easy." Kermitfrog http://www.youtube.com/watch?v=hpiIWMWWVco

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RE: i have a problem

Changing impellers on multi stage pumps can be an expensive business and take weeks to complete. If they are single stage pums there is still a lot of work to be done.

Condider buying an extra pump to increase the flow if possible. Alternatively you may strip one of the pumps and check up on the impeller bearing clearences to see if there is wear, you may wish to strip down and check its condition and the state of the imellors, they may need changing.

There isn't much information available in your profile and I don't know what country you are in, but in the UK there are company registers such as Compass. These list all the manufacturing companies in the UK and you need to look under 'Pump Manufacturers'. Once you have found a manufacturer they will be able to advise you in detail.

I hope this information helps you with your problem.

 

RE: i have a problem

I notice there is an American pump manufacturer called Worthington Pumpss, is that the pump you have? I notice you have increased the prime mover HP by 40%. Did your flow improve from the original motors?

Surely you will contact the pump manufacturer and ask for specifications for these pumps for pumping salt water. If you are consuderably below these specifcations then maintenane does seem the answer.   

RE: i have a problem

Pump models manufactured under the Worthington name for the United Stages are now owned by Flowserve which still provides parts and service for the older models.  I would suggest that you contact Flowserve and ask them for upgrade options and parts availability.

Johnny Pellin

RE: i have a problem

Impellers may already be at max diameter, find a curve and measure the impeller dia in your pump. 8LN is a very common Worthington pump model, but I don't believe Flowserve supports this anymore... check around for 3rd party pirate shops, replicators, etc. Most pump mfg can reverse engineer and create a new pattern, but it's expensive.  

Consider increasing the speed on your engine as well to gain more flow. You'll need to check NPSHa vs NPSHr and power req.

Did you know that 76.4% of all statistics are made up...

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