pipe lengths for pumps 3

[farren]

What is the usual length of the suction pipeline from a storage tank to a pump and also the length of the discharge pipeline from the pump to a mixer?

 

[itdepends]

In my experience- on the suction side- anywhere from 0.5m to 20m.

On the discharge side- anywhere from 5m to 1000m.

There is no real "usual" lenght- it depends on the equipment layout.

 

[gr2vessels]

The "usual" has been replaced by "cost" for a lenght of pipe and by the "required minimum space". The calculation starts with the minimum possible distance for access, removal, etc..The mixer inlet should be connected, if possible, to the pump outlet isolation valve.
cheers,
gr2vessels

 

[chief]

The suction should be as short as possible,after allowance for a filter box and isolation valve.If possible without elbows to give a streamline flow to the pump.The suction manifold dia preferably oversize of the pump suction inlet to ensure positive flow.
The discharge length to your process depends on the amount of pipe pressure losses you can allow and still effectively operate.

Offshore Engineering&Design

 

[PAN]

You should calculate your NPSHa in comparison to NPSHr.

If this is oil storage tank per API 650, pump may be placed outside the bund wall area.

 

[bimr]

Suction piping should be as short as possible.

Desirable velocities in suction piping should be 4-6 ft/s.

Desirable velocities in discharge piping should be 6-8 ft/s.

3-4 diameters of straight pipe between the pumps suction connection and the first elbow are recommended.

Use long radius elbows on pump suction.

Use eccentric reducers on pump suction with flat side up to prevent air pockets.

Refer to Hydraulic Institute Standards for pump piping arrangement.

 

[MJCronin]

farren,

In addition to having a short suction piping length, it is also a good idea to have the suction piping "one-size" larger than the suction nozzle of the pump.

This usually ensures that the fluid velocity is in the 4 - 6 ft/second range recommended above.

-MJC