How make central priming system for centrifugal pumps? 1

[VladimirWH]

Hello!

I have some problem with central priming system (scheme attached). So, I have three centrifugal pumps (Q=1300 m3/h; H=90m; N=500kW), two of them primary, third - standby (P-001,P-002,P-003 in scheme). All system works on pantoon (barge), it's low lift station like. Customer want to use vacuum priming system to start each pump automatical. And I can not undestand how it must works. I figured priming system: it's "start" at discharge line between pump oulet and valve, next mount water detector (ultrasonic) (LT001), next valve with actuator (V-017), next strainer (S-001), vacuum pump (P-004) and tank (T-001). I add valve (V-021) to fill vacuum pump for first start. Detectors LT-004 and LT-005 to monitor water level in T-001. I want to repeat - all system automatical. So, I have a quiestions: Do I right, when added liquid detectors (LT001)? How I can command "turn off" to vacuum pump, when centrifugal pump is filled? And general question: am I on right track with that scheme?

 

[Artisi]

A couple of ways to go about it, vacuum pump as you have shown or ejectors on esch pump discharge - suggest looking initially as to how and worry about logics later.
Are the pumps vertical or horizontal type?

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.)

 

[VladimirWH]

Are the pumps vertical or horizontal type?

Centrifugal pumps - Horizontal Split Case Pump.

 

[MJCronin]

Wild idea here ...

Have self-priming centrifugal pumps been considered ?

Why must the pumps use a vacuum system ???...... Oh, thats right !!! ..... The client said so .....

How about a big-old-nasty Gorman Rupp Cast Iron Pump?

https://www.jmesales.com/amt-gorman...BaGUg1C43xBuCGnx1iLTNiGP5ggczf3oaAvRZEALw_wcB

MJCronin
Sr. Process Engineer

 

[Artisi]

Yep, wild idea - haven't seen any 500kW Gorman Rupps anywhere

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.)

 

[Artisi]

Why HSC, has the client considered vertical pumps, overcomes the priming problem, push the start button and you've got water?

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.)

 

[LittleInch]

The problem I have with your scheme is that you don't have anywhere an ability to not suck water through your vacuum system which tends not to like it.

Try and find an air eliminator valve which works on vacuum and use that.

Like this [URL unfurl="true"]https://res.cloudinary.com/engineering-com/raw/upload/v1631083649/tips/47_fy3wbt[/url]

Or talk to someone like valmatic.

What you're doing is straightforward and has been done many times before so no need to invent the wheel again

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

 

[Artisi]

LittleInch, vacuum pump could be water-ring type, plus there are many vacuum primed pumps on the market from which you could crib the priming system and adapt as a common unit to serve all the pumps or fit one to each pump.

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.)

 

[Artisi]

1 idea for priming

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.)

 

[LittleInch]

I agree but it seems much cleaner to separate the water from the vacuum system if you can.

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

 

[HTURKAK]

Hello VladimirWH ;

I think Z - 001 ,Z- 003 and Z- 005 on the inlet piping are strainers and there are no foot valves..

A cheap method is to install foot valve on the inlet end of the suction pipe and prime the pumps by filling teh system with water from any source ( in this case from outlet piping could be an option)..

the following picture ( excerpt from PUMP HANDBOOK by IGOR KARASSIK ) could be helpful to see the vacuum concept.

Good luck ..

 

[pierreick]

Hi,
Consider this link :

https://vacuumprimingsystems.com/learning-center/how-does-it-work/how-does-it-work-video/

Pierre