BALANE LINE

[U0U0I]

HI

I do know that the balance line is for decreasing axial force in centrifugal pumps and of course the orifice is for controlling the flow between discharge and suction (by pressure reduction) but I eagerly want to know what is red circle in the attached file. check valve or ....???

thanks

 

[Compositepro]

My guess would be an expansion joint.

 

[bimr]

Looks like a valve.

 

[PumpSmart]

could be a visor for visual inspection.

 

[MikeHalloran]

I'm not seeing an attached file.


Mike Halloran
Pembroke Pines, FL, USA

 

[Compositepro]

Let me elaborate on why it may be an expansion joint. It is a mechanical scale drawing, not a P&ID. The device physically matches an expansion joint. Also, the device is in a short run of rigid, flanged pipe joining two parts of a rigid pump body. Some flexibility must be provided in this pipe to allow for assembly and reduce stress.

 

[JJPellin]

I have never seen an expansion joint in a balance line. I was not able to view the drawing. But, if one end of the balance line is part of a head or cover and the other portion is part of the case, then a joint is needed. We have two large Coker jet water pumps with rigid balance lines. One of them has a joint in the middle that is a Graylock clamp. The other one has a pair of tongue and groove flanges with a venturi orifice fitting in the middle. This is not to restrict the flow. It is there to provide a pressure differential that can be correlated to flow. There would be no reason for a check valve or flow restriction orifice in a balance line that I am aware of. If you could re-post the attachment and other details about the pump, we could comment with more certainty.

Johnny Pellin

 

[clay87]

Regarding the expansion joint concept, I have seem some balance lines with spiral/loop in the piping presumably for thermal expansion.

Somewhat related side question: Why don't balance lines have venting capability?