Two different flow pumps from same suction line.

[Bartender9]

Hi everyone.

I need some help here. Currently I'm working at a proposal where a new 6" pipeline with two multistage vertical pumps (one running, one standby) will be installed on an existing 8" suction pipeline where this same pipeline also delivers flow for 5 existing booster pumps (also multistage vertical pump). The booster pump has a maximum delivery flow of 30m³/hr and pressure head of 6 meters. The existing booster pumps are controlled by a VSD where a pump will kick in when more flow is required. For the new 6" pipeline, the pump is proposed with a maximum delivery flow of 51m³/hr with a pressure head of 8 meters. Both new 6" pipeline and existing 8" pipeline deliver flow to different location, meaning same suction source but different delivery line. The new 6" pipeline will be tapped in approximately 2.5 meters from the existing booster pumps.

My questions here are:

1. Is it possible to installed the new 6" pipeline with the two pumps without starving the existing 8" pipeline.
2. If not possible, what is the alternative for this proposal other than to create a single dedicated line for the new 6" pipeline.

Well, that's my problem. I hope you guys can give me some advises over this matter. Thank you.


Regards,
Bartender9

 

[LittleInch]

So basically you are going from 150m3/hr to 201 at full flow in the pump inlet line.??

Is it possible? Maybe yes, maybe no.

All depends on the pressure available in the inlet line / existing now and what is feeding it, length of pipe, elevation difference from liquid head to pump inlet flange, NPSHR of the pumps, fluid, vapour pressure, temperature, density, viscosity etc etc. So far we have none of this so cannot give you an answer.

200 m3/hr down an 8" line is not bad, but without data and a schematic, impossible to say I'm afraid.

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