what choice in pump type?

[Lekoso]

I have a fundamental question.

What informs the type of pump for a specific application and what informs those choices?

From experience, I find the Centrifugal horizontal split case being deployed for Fire fighting purposes?
Any reason(s) why and any referals to that effect?

Also, I noticed that LPG pumps used the multistage centrifugal pumps.....any reason(s) and referals

Thanks and Regards

'Lekan

 

[wimple]

It really depends from the operating conditions case by case, i guess.

In my experience in water industry, I used monocellular pump for head up to 100 m and from low flow to 1000-2000 m3/h

Horizontal Multistage pumps from 60 m head up to 500-600 m head and flow up more 1000m3/h

Vertical multistage up to 240 m for boosting genrally let say, or due to space limitation

Horizontal split pump double volute, for head up to 250m but higher flow capacity (3000 m/h3), in parallel it can handle high flow applications (like 200000 m3/day)

At the end of the day, very often I had multiple solution to handle required service, and choose according efficiency and cost.

 

[Artisi]

If you look carefully you might find for flows which are capable of being produced by end suction centrifugal pumps of 150 - 200mm dia discharge are used and HSC pumps after that - this is based on economics of manufacture.

As for LPG pumps (not an area I know or deal with) I would think that multistage pumps are used as the heads generated tend to demand this pump style.

 

[786392]

Usually in warmer climates with ambient temperature highs ranging 40~58 degrees Celsius under sunlight;It is observed that vertical multistage(submerged barrel sump type) centrifugal pumps perform much more efficiently as compared with horizontal multi-stage pumps.
Reasons most probably

liquid LPG NPSH available remains better in 1st type case as well as sunlight exposure impacted high temperatures Stay at minimum.

Whereas for horizontal multistage pumps both the items are at Risk;
As for same pipeline configuration,grade levels we observe relatively lesser NPSH available& Higher temperatures effect state of LPG i.e. partial vaporisation thus cause vapour locking/loss of efficiency.

Best Regards
Qalander(Chem)

 

[MJCronin]

lekoso...

Get a copy of the "Pump handbook" and review the sections on applications.

You will find that certain pump types have evolved to suit the demands of the service.....This is simply the effects of a manufacturer trying to meet the need of the marketplace.

Horizontal split case pumps demand low NPSH, are available in many capacities and are reasonably priced. With NFPA-25 certification, they become a "best choice" for fire protection service.

LPG pumps probably have modest flow rates, but much higher heads required, hence the multistage choice. This is what is demanded by the marketplace.

If you can get a hold of the Goulds Pump Catalog, review it carefully and read between the lines. Pumps offered are really for specific services.

My opinions only....

-MJC