Pumps and Valves

[MrProjectEng]

Hello;

How should be pump, non return valve, and manual valve combination? Is there any line up type to get more efficiency?

Normally after pump; non return valve then manual valve could be line up. That is inevitable?

 

[pennpiper]

MrProjectEng,
Two things:
#1 This has been asked before, why don't you try the "SEARCH" option before you post a question?
#2 What are you trying to do, reinvent the wheel?

Here is some advice:
- Centrifugal Pumps: First comes the discharge of the pump, then comes the Check (Non-return) Valve then comes the Block (Isolation or Shut-off) Valve

- Positive Displacement Pumps: First comes the discharge of the pump, then comes the Block (Isolation or Shut-off) Valve. A Check (Non-return) Valve is not required for PD Pumps because of the nature of the PD Pump.

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

 

[LittleInch]

Thought I'd seen this before and last time I got voted down by saying it could be the other way around.... All depends on what you're using the NRV for, how often it closes and how long it needs to sit there before the isolation valve is closed.

See

http://www.eng-tips.com/viewthread.cfm?qid=410093

for all the points raised.

Also depends on your type of PD pump. Some come with integral NRVs ( diaphragm, piston, some don't ( screw, gear etc)

What do you mean by "efficiency"?? Efficiency of what? - space, pipe size, pressure drop?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[BigInch]

You didn't get voted down. There were other opinions expressed by other engineers that worked for them in their particular situations, but those arrangements also introduced what could be classified as disadvantages if used other situations. There is no general rule for all situations. I advise each engineer to reach his own conclusion as to what works best for the system at hand.

 

[MrProjectEng]

I would like to ask these combination for positive displacement pumps.

Check valve and isolation valve is reversed as using with it. So pump, check valve and isolation valve lines up you said so...

Why is that??

Thanks

 

[BigInch]

Reversed? Reversed from what?

 

[MrProjectEng]

Reverse components on line ....such as check valve and isolation valve...

Normally centrifugal pumps are using check valve and isolation valve line up...

For Positive displacement pump this line reverse for check and isolation valve as writing above... Why is it doing that?

Thanks

 

[Artisi]

For me it would be NRV after the pump and then isolating valve - why,allows isolation of the line to attend to / remove the NRV that is probably more troublesome than an isolating valve.
Of course each to his own preference.

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.)