strainer installation

[prens11us]

For fire water pump having 20" suction nozzle, is it required to install a strainer. The fire water is supplied from a water tank.

 

[BigInch]

A temporary strainer is always nice for start-ups to catch gloves and welding rods and a couple of pounds of weld beads, etc.

If your tank contents can be made free from delaterous materials, scales, salt chunks, or your intakes are well placed or filtered, you might not need one, but in which case its always a good idea to make a provision to have a strainer installed at a future date if you can't buy one now. Operations will probably put one in some day. Tip: If you at least leave a provision for installation, maybe you can still keep your job when it happens.

Going the Big Inch!

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[EdStainless]

How does, "it depends" grap you?
I have seen stainers clog, colapse, and get sucked into the pumps.
I would suggest that you look at two stages of inlet protection. A large coarse strainer, and then a finer one after it if it is needed.
Witha 20" intake I imagine that your pump can handle some sizable debris without damage. Check that out first.

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[BigInch]

Strainers are not maintenance free.

Going the Big Inch!

http://virtualpipeline.spaces.msn.com

 

[JJPellin]

I would suggest not installing a strainer. They have tended to cause me more trouble than they are worth. If the solids that you are like to see will pass through the pump, I would let them pass. I only use strainers for startup of brand new system and for towers where I know I have a history of scrap iron. In all other cases, if there is material present that will plug the strainer, then it plugs up, the pump runs dry and wrecks. If there is no material that will catch in the strainer, then I am just imposing a lower NPSH on my pump which can increase the chances of cavitation or other problems.

 

[BigInch]

We monitor our suction pressures, use heavy basket strainers and put dPs on them. No problem, for them or for the pumps either. As I said, you must clean them out when they're blocked.

Going the Big Inch!

http://virtualpipeline.spaces.msn.com

 

[Artisi]

To pharaphrase a well known quotation, "to fit or not to fit that is the question" - and is really an informed decision based on 2 simple questions;

1. Why do I need a strainer?
2. Why don't I need a strainer?

Question 1, because there is the likelyhood of solids gaining access to the water tank, therefore I need a strainer.

Question 2, because the water tank is enclosed and no solids are able to gain access to the tank, therefore I don't need a strainer.

I see no other reason that needs any consideration.

Naresuan University
Phitsanulok
Thailand

 

[Ashereng]

How often do you expect your fire water pump to run?

In that time, do you expect enought "stuff" to go through the pump to cause it trouble?

If the answer is not much and not much, then I would not use a strainer.

If the anser is yes and yes, then I would suggest you get better water.

"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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