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dc_Death
15-01-2013, 03:54 PM
Hey Guys-

So im working on a new project, and trying to pump liquid refrigerant(134A) with a Delta P of 375 PSI, up to 510 +- Flow rate will be between 14-18 GPM. I am having a difficult time tracking down a pump. At first thoughts, i was looking for a gear pump, but people advised me that would not be the best. I received a quote on a Regen turbine pump for 16K USD. That is way too much for this project. I know vane pumps are used regularly at lower pressures, but i believe that may be the best for my application, if one can accommodate high pressures.
Any thoughts you may have are appreciated.

Thanks,

flyinkiwi
15-01-2013, 06:52 PM
Sounds like an ORC application.

If so, chances are it will be a highly specialized pump, with an equally specialized price tag.

Goober
15-01-2013, 08:15 PM
ORC application? ORC stands for?

dc_Death
15-01-2013, 08:34 PM
ORC stands for organic Rankine cycle.

Yes, it is similar to an ORC, but not the same.

There has to be some manufacturer that builds something to suite. Maybe a multiple stage centrifugal?

Magoo
15-01-2013, 09:28 PM
Google hysav, they do a refrigerant pump

dc_Death
16-01-2013, 03:10 PM
Yea, need those hysave pumps about 10 times the pressure. But they do look like the right type of design. Simple & strong.

chemi-cool
16-01-2013, 03:28 PM
I used to be the installer here of Hysave pumps to increase liquid pressure and decrease head pressure.
in the winter they pushed liquid pressure by 30 psi, in the summer they were totally useless.

Talk to them, they might have new products by now: http://hysave.com/

Magoo
17-01-2013, 01:14 AM
Think outside the circle, cascade a couple of pumps, they will have a working differential limit per pump.

sandybapat
17-01-2013, 04:33 AM
I have seen, almost 20 years back, a Liquid Ammonia pump which was pumping liquid from a atomspheric pressure Ammonia storage tank to 15 Bar user point in fertilizer plant. I think that was a pistone pump (positive displacement). In chemical & fertilizer plants such type of pumps might be used for pumping volatile liquids.

Sandro Baptista
17-01-2013, 10:10 AM
Yes Sandy, I also agree with you piston pump it would be a very good solution.

dc_Death
17-01-2013, 03:54 PM
I was under the impression that piston pumps would cause irregular pulsations, resulting in problematic fluid-gas? If this is not the case so much, maybe they should work fine. Maybe stacking a centrifugal pump in front of the piston pump to feed it plenty of fluid.

Coorsman777
17-01-2013, 05:16 PM
I have not used one but asked a supermarket rack manufacturer about them and they told me the installed them on a few systems and all of them are disconnected because there was a problem with flash gas in the liquid line due to the pressure change or something like that.

RANGER1
18-01-2013, 02:02 AM
Its only a suggestion but it could avoid an expensive pump to a more standard less expensive pump.

Depending on exactly what you want to achieve if it is possible to have an intermediate transfer vessel.
Usually called a liquid transfer or pump-drum.

1/ First lower pressure 375psi drains into intermediate vessel with a vent back into 375 psi vessel so it freely drains.
2/ Intermediate vessel is isolated from 375psi vessel.
3/ Intermediate vessel is then equalized to 510psi vessel.
4/ After equalization use pump to tranfer liquid with a then very low dp.
5/ when level is decreased stat the cycle over venting intermediate vessel back to 375psi vessel.

Use of low pressure drop non return valves & solenoids essential.
Also a small canned or mag drive pump may be able to be used (no shaft seal)


After saying all that cannot see why a gear pump would not work, the only danger would be possibly lubrication & type of shaft seal.

Have you contacted Viking pumps?
A quick looks shows Viking LVP rotary vane transfer pump with 14bar or 200psi differential

dc_Death
19-01-2013, 12:29 AM
Yea, the intermediate transfer vessel would work, but seems like alot of trouble. I will look more into the viking pumps. Looking at their website, looks like the max case pressure allowable on the Viking vane pumps is 300 PSI. Maybe that will work for the primary pump.
any good centrifugal pumps for refrigerant?

mad fridgie
19-01-2013, 02:47 AM
http://www.hermetic-pumpen.com/en/refrigeration/pump-types/
Contact these guys, they should be able to help.

Sumit
21-01-2013, 05:05 AM
generally, we use reciprocating pumps in this case because of cost cutting.In addition, they work well and no problem in it except in summers.They work efficiently for first few hours and then their efficiency decreases.

dc_Death
23-01-2013, 04:29 AM
Sumit-
So you would say maybe a CAT pump? By reciprocating, i believe you mean a piston-style. How are the pulsations? Wouldn't a piston pump pull a vacuum on the inlet when stroking? Do you believe that i would be able to use another pump to supply a pressure to the inlet side of the reciprocating pump?

Thanks for your input.

sandybapat
23-01-2013, 11:38 AM
What is the pressure and temperature of liquid to be pumped. If you have subcooled liquid then there will not be problem of flash gas.

sterl
28-02-2013, 07:51 PM
As one step its either a piston or a diaphragm pump. Either one would want a centrifugal upstream as an NPSH boost unless your system arrangement has considerable head and subcooling available. A diaphragm is more like wear and erosion resistant and a lot simpler to make chemically compatible.

Both are going to pulsate; though a hydraulic accumulator would tend to take it out.

Only smooth flowing piece would be a side channel or regenerative multi-stage. Both are going to be highly critical to NPSH.

18 GPM at 510 Psi is going to be at least a 15-Hp pump. None of them are going to be cheap.

greenscape02
20-03-2013, 09:00 PM
Try calling Hansen Technologies. On their website (hantech.com) they had a hermetic liquid refrigerant pump that can go up to 600 psig. Also, I read about Viking pumps above. Viking makes a very good pump and if you need another option check Tuthill....a competitor to Viking.

Check out www-heat-pump-pro.com (http://www.heat-pump-pro.com) for great heat pump information!