pump control vales

[gunner]

Hi Everyone,
I've recently aquired a Totton GP28/11 pump to use in my new brewery build, just wondering if it makes a difference which side of the pump a valve needs to be for regulating the flow of the pump. Would it be better on the inlet side of the pump or the outlet side or doesn't it matter with this type of pump?

regards

gunner

 

[markp]

I'm not an expert.....but IIRC they do not like a restriction on the input.
You can restrict the output using a by-pass loop and a ball valve.

 

[Vossy1]

Mark is right, restrict on the outlet :thumb:

 

[Darcey]

I have been considering a similar question. I am looking at pumps and things.

....You can restrict the output using a by-pass loop and a ball valve.

by-pass loop?

 

[markp]

By pass loop - a t-junction just after the pump output. One leg recirculates back to the input and the other goes to the ball valve. The extent to which you open the ball valve governs what comes through and what gets recirculated back to the input.

 

[Darcey]

That is what I assumed. I was looking at a pump in my LHBS yesterday, it ha 1HP and sounds like its abit of a beast. Are pumps best run thru a power controller? or just leave running with the bypass loop?

If Im doing a slow sparge is it best to leave the pump running and just slightly open the valve? or would it be preferable to plug the pump in to a controller (which I havnt even thought about yet..)

 

[markp]

Darcey,
From what I know, you just control the flow using the by-pass loop and opening the ball valve. I think the controller would try and slow the pump down and I'm not sure if it would like that.
One of the resident engineer peeps will no doubt be able to add more to this.

Are you just going to use the pump to recirculate and drain your mash tun?
If so, I have a pump for sale that might suit you :whistle: .....I actually bought it from Vossy here and tbh have not even used it myself as I decided to go a slightly different route and a slightly different pump.
The pump is a totton and rated to 85 deg IIRC.....let me know if you want anymore details.

ATB

 

[Darcey]

That is exactly what I am after. To be part of a herms and to pump into the boiler. D

 

[Springer]

it a 1HP and sounds like its abit of a beast.

:shock: :lol:
"My thats a big one " remember, ? as the man said in the film. Are you sure about that D, it certainly sound a bit of a beast, as you say. That will need a lot of taming for a herms set up, ok for CIP and sprayballs, for sure. Is it going at the right price, second hand, ? :?
By pass is the way to go, controllers are not necessary.
S

 

[Darcey]

It was not the right price I just asked what they had. Budget is always a problem for me

 

[Springer]

Yes, I always go for the most "economical" solution, for me cos I like the challenge. When I was looking at pumps for my HERMS set up, I thought this was one instance when a new purpose built bit of kit was required, so when out and spent the money, you don't want a pump failing in the middle of brew day.

S
One H.P. still :shock: :lol:

 

[graysalchemy]

I saw that pump as well the other day if you want to spend that koind of money you may as well go for a march may pump of ebay.

 

[unclepumble]

The best way of control is throttle the outlet and use a Bypass Loop as Mark P said.

Put a ball valve in the bypass loop to control feedback to the inlet from the outlet as well as a ball valve on the outlet pipework, after the inlet of the bypass loop, and you will have a very controlable pump.

With the bypass valve full open and the outlet valve closed the pump will run at full speed no issues as the liquid just recirculates with no detrimental affect on the pump, (there is no backpressure or overloading on the pump due to the recirculation loop) if you close the bypass valve in this state the pump will labour, and not perform well longterm.

To increase flow open the outlet valve slowly, and close the bypass valve in proportion to the opening of the outlet valve.

Using this method can give you very good control and will allow the use of the pump for high speed pumping (CIP) operations and also make it useful for sparging.


UP

 

[jokeyjon]

Would the March May pumps also benefit from a bypass loop, or is it OK just to throttle the outlet with a ball valve :wha: ? I have a vague recollection that magnetic drive pumps were fine with throttling on the outlet valve as the magnetic coupling simply breaks and re-engages without overheating the motor.

 

[unclepumble]

Would the March May pumps also benefit from a bypass loop, or is it OK just to throttle the outlet with a ball valve :wha: ? I have a vague recollection that magnetic drive pumps were fine with throttling on the outlet valve as the magnetic coupling simply breaks and re-engages without overheating the motor.

It will work ok with throttling, but for best service life, less load on the pump ect, you are always better with a bypass loop.

UP

 

[Vossy1]

I know UP has vast experience with pumps, but I have to say that I'd really only use a by pass loop on pumps which were severely restricted output v capability. The March pumps are fine IME with full restriction as their output is so low full bore, it's hardly worth the difference.
The only thing you are likely to need to replace on the March pump if restricting a lot, is the small thrust washer that seats between impeller and housing, and they're readily available from March.