determining suction and delivery lines of centrifuagal pump

[thunderspeed]

For a centrifugal pump
what significant signs I can see from outside of a real pump mounted in a system in order to differentiate between suction and delivery lines of centrifugal pump ?

 

[pennpiper]

thunderspeed,
Attach a photograph and someone here will help you.

Sometimes its possible to do all the right things and still get bad results

 

[JJPellin]

The suction flange is usually larger than the discharge flange. If you know the rotation of the pump (cw or ccw), you can often tell by the orintation of the flanges relative to the shaft centerline. A picture would certainly help us help you.

Johnny Pellin

 

[thunderspeed]

Well I don't have a picture its an engineering job interview question (orally)
are you sure ? I thought that was for the compressor only.
The only thing I can think about now is that the discharge might have a check valve while suction not . Maybe the discharge might have a flow control valve and suction not as well . Is there another sign we could tell ?

 

[rotw]

I think you often have a convergent (reducer) at inlet and increaser at outlet...
This is something you would normally recognize in pumping stations (booster pumps).

"If you want to acquire a knowledge or skill, read a book and practice the skill".

 

[pennpiper]

Thunder,
You wrote:"Well I don't have a picture its an engineering job interview question"

What is the job you are interviewing for?

Sometimes its possible to do all the right things and still get bad results

 

[Artisi]

There must be millions of photo's / drawings on the net of pumps, well I would suggest you have a look and undertake some self education. A clue for you is the inlet leads to the eye of the impeller.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[bimr]

Image of pump installation:

 

[Pumpsonly]

Thunderspeed, you already provided the answer your self in your 24-Aug post.
It is easy to identify the the suction and discharge for an end suction pump. But not that simple for
vertical inline pump, Multistage, axial split case, VS6 type. Here the OP mentioned about a complete mounted system.

 

[JJPellin]

Yes, the suction flange is usually larger than the discharge flange. This is true of pumps as well as compressors. As a generic interview question, I would have the following two answers:

If the suction and discharge flanges are different sizes, the larger one is the suction.
If there is a check valve in one of the lines, that is probably the discharge.

Johnny Pellin