[Smackre]

Say you have 120 gallons of coolant. Oil coolant. That is raising 16 degrees per hour. But you wanted it to stay below 70 degree's always. How would you go about keeping it cool. From my calulations you need some place around 14000BTU to cool the oil off.

I have been looking into afew options.

One is pipeing it into the ground into geothermal lines to cool it off.

Another is to pipe it outside and run a big fan on it. A radiator type of design.

Another would be refrigeration cooling. But that is very $$. But a option.

A third would be buy a used machine like this.
http://www.hgrindustrialsurplus.com/...entPageIndex=1
Now I talked to the manufacture of that thing I just linked. They said it was a 23000 BTU unit. Now I also talked to a heating and cooling guy and he said he dont think there is no way its 23000BTU. He though it was more like 2400BTU max.

So how would you guys go about cooling this oil. We are looking into a solution that is long term but economical.

[timlkallam]

14000 btu is just over a ton of cooling not much .I would try this just to see if it would work get a used 2 ton (24000 btu) window air conditioner. Take the cooling coil out of it. Extend the suction line and liquid line . Recharge it .And drop the cooling coil in the coolant. You would have to get someone that does refregeration, it shoud not cost
much.
If that works I would go to a moible home supply store and get a 2 ton ac split system that comes pre charged with freon put the condenser out side the cooling coil in the tank.It would cost around $1500.

[Smackre]

Do you think there would be a issue with condensation. I cant get water in the oil. And if condensation gets into the oil it pretty much ruins it.

[Delw]

What I did on one of my mills was run the coolant lines through a hydraulic radiator and had 2 fans blowing threw it. It already had shrouding and 1/2 or 5/8s lines ( cant remember which ones)
for production jobs it kept the oil cool.
the machine held 50 gals of oil and got hot very quickly. the radiator works pretty darn good.

I also used this same type of set-up but a smaller one for a lathe we ran oil on. that we ran 304 stainless threw a barfeed with fast cycle times and heavy cutting along with deep hole drilling.

[Smackre]

how hot was your oil getting? I am running a centifuse cleaning machine on my oil. And it has 2 4hp pumps and large centifuse tanks that heat the oil up. I ran the oil 6 hours today and it went from 70 Degree to 116 Degrees. It seems to max out around 116 Degree so I need to cool it off 46 Degree's.

[ConKbot of Doom]

Do you think there would be a issue with condensation. I cant get water in the oil. And if condensation gets into the oil it pretty much ruins it.

as long as the evaporator is completely under the oil, and you have insulated lines running to and from the tank, it should be good... however then you have oil leeching/wicking back up whatever insulation you have on it.

[Delw]

how hot was your oil getting? I am running a centifuse cleaning machine on my oil. And it has 2 4hp pumps and large centifuse tanks that heat the oil up. I ran the oil 6 hours today and it went from 70 Degree to 116 Degrees. It seems to max out around 116 Degree so I need to cool it off 46 Degree's.

It was very hot to the touch. parts were hot when they came off.
I don't know the temps but consideirng we ran them in a swamp cooled shop and at night when we left the shop usually got to be around 90+(az) since we shut all but one cooler off. so the oil was 90 easy when we started up in the morning than 12hours of running gets it pretty warm too.
before we had to set the piece's in inspection for a few hours too cool off to check, after the radiator idea they were semi cool going into inspection.

with the fans running on them hydraulic radiator you would notice a considerable difference.
might not work in your application but use this info for some other ideas. Like maybe a big radiator and run a swampcooler through through it to cool the oil off faster. ( they make little ones that have some serious cooling power)

It beats buying a chiller system for your coolant tanks. I know machine shops that have them and they are expensive

[RICHARD ZASTROW]

It depends on your shops heating and/or cooling needs, but many shops recover the heat as needed and vent it outdoors when not needed. Works for air compressor and hydraulic systems as well. Just a thought.

Dick Z

[NC Cams]

The lowly aoto ratiation does a FINE job of dissipating heat. I know of a guy who used a bunch of radiators and fans and cooled his quench tanks for a production induction heating/heat treating process. He dumped the heat outside in the summer and recovered it in the winter.

If you contact some radiator suppliers you might find someone who can give you the heat transfer data you need to calculate what you're trying to do. More than likely, however, you're going to hunt and peck. The point is, a typical auto radiator will transfer HUGE amounts of heat and do so quite effectively and efficiently - they do it without even thinking in a car and those have a high underhood thermal density.

Yes, you can also use geo thermal. Ford used the "wading pools" at corporate for their dynos for years and may still do for all I know. Just make sure you don't cross contaminate. The use of water to water or water to oil heat exchangers take care of that - just don't let them mix/leak or the EPA will burn you BADLY. For that reason alone, i'd go oil/water to air heat exchange simply because of the pachaging issues.

THe one isssue with radiaorts that is a PITA can be pumping and circulation - especially purging of air. Once you get solid coolant flowing, things work pretty well and predictabley.

[Geof]

Say you have 120 gallons of coolant. Oil coolant. That is raising 16 degrees per hour. But you wanted it to stay below 70 degree's always. How would you go about keeping it cool. From my calulations you need some place around 14000BTU to cool the oil off.....

I think you will find that you have to go for some form of refrigerated chiller; if you want to stay below 70 degrees you need either air or water several degrees below this. Using something like an automobile radiator would need air at around 55 degrees maximum to get the oil below 70. Using a liquid to liquid counter current heat exchanger you may get away with a difference of only 5 degrees lower but it depends on how much area there is in the heat exchanger and the flow of the cooling liquid.

How cold is the water supply in your area? The simplest solution would be a water cooled heat exchanger just using the water supply if it is cold enough and you are not paying much for the water. However, this is not likely to work in the summer.

[Teyber]

Say you have 120 gallons of coolant. Oil coolant. That is raising 16 degrees per hour. But you wanted it to stay below 70 degree's always. How would you go about keeping it cool. From my calulations you need some place around 14000BTU to cool the oil off.

I have been looking into afew options.

One is pipeing it into the ground into geothermal lines to cool it off.

Another is to pipe it outside and run a big fan on it. A radiator type of design.

Another would be refrigeration cooling. But that is very $$. But a option.

A third would be buy a used machine like this.
http://www.hgrindustrialsurplus.com/...entPageIndex=1
Now I talked to the manufacture of that thing I just linked. They said it was a 23000 BTU unit. Now I also talked to a heating and cooling guy and he said he dont think there is no way its 23000BTU. He though it was more like 2400BTU max.

So how would you guys go about cooling this oil. We are looking into a solution that is long term but economical.

http://forums.extremeoverclocking.co...d.php?t=101902
Linked is a computer overclocking forum. I am not going into details, but you can follow that similar method and run the coolant through it... not sure how many btu's you would need, but you could tune for capacity instead of low temps. Add a txv or cpev and i think that you could manage to keep that thing far below ambient for relativly cheap

Hope this made sense. Just a cool idea.

Regards

[RICHARD ZASTROW]

Just for grins, you might want to google "heat pipe". I was just there looking for an idea to cool the oil in a 60:1 gear reducer. Relatively inexpensive & no moving parts. Have to dump the heat with some sort of heat sink etc. (preheater for water heater?)

Merry Christmas,

Dick Z

[Caprirs]

The chiller listed in the first post states a capacity of 2 hp. That equals to about 1.5 KW. From what I can find 1KW-hr equals 3512 BTU/hr. So if you need to move 14K BTU/hr, four of those chillers would be required.

I think the automotive radiators are a good suggestion. Even the wimpiest econobox car has an engine rated at 60hp. That means the cooling system has to be capable of rejecting approximately 60hp to the ambient air although it does not have to achieve ambient temps and it has a 60hp engine to drive the fan and water pump. Get a radiator for a heavy duty pickup truck, especially if it has an integral electric fan with shrouding. Then all that is needed is a 12VDC source.

[NC Cams]

It is purely a function of Delta T and Q where Delta T is the temp differential and Q is the amount of heat you're trying to dissipate.

The auto radiataor trick WORKS. It is cheap, easy to implement and anything but elegant. The amount of heat you need to dissipate is known. THe temp rise is all that you're trying to control.

If an auto radiator or radiators can keep a 100 thur 600 hp engine cool while dissipating perhaps a 70% thermal inefficiency factor, surely, keeping much less of a thermal load should NOT be a major undertaking. Chances are, you might even be in a sitaulation where you can overcool for the thermal load predicted. If so, simpyl slow down the coolant flow rate and/or the air flow thru the radiators or perhaps via the thermostat which you'll surely implement.

The plumbing of an auto radiator is not a major issue - not with PVC or tubing as it is anymore. Ditto that for pumps as it is now possible to find simple recirulating pumps ala what they use on IC engines. We found some real nice small 4 cyl Ford pumps that darn near drove themselves when we crafted up a supplmental cooling tower for a dyno quite a few years ago. Once you get the air out and managed, the thing dumps heat simply and effectively.

Besides, when you go to/with water to water heat exchange, you can regulate temps to unglodly close tolerancese even without relying on city water. The city water does the final "tuning" - the radiators dumps most of the heat whiichi is the hard part of the problem.

Calculating the heat flow WITHOUT knowing how much heat you can dissipate ACCURATELY thru the radiatiors is the PITA part. Finding out the heat flow consants is NOT an easy thing to dig out. The radiator guys don't offer up their secrets that readily. Reason: becuase underhood air flow is all EMPRIICALLY evolved and confrimted - they test the hell out of them based on SWAG"s and Calculations.

Solution: pick some big radiatiors. Force a bunch of air thru them and adjust the available vairables to get the Delta T you can live with from the Q you can dissipate.

[RICHARD ZASTROW]

Is the oil cooler from an automatic transmission adequate? Or multiples in a stack with a fan between? Oil to air heat exchanger using parts from the local junk yard?

I would still follow NC Cams suggestion on collecting data. Then you can share it with the rest of us on the Zone. We won't tell anybody, promise!!!! lol

Dick Z

[Teyber]

The chiller listed in the first post states a capacity of 2 hp. That equals to about 1.5 KW. From what I can find 1KW-hr equals 3512 BTU/hr. So if you need to move 14K BTU/hr, four of those chillers would be required.

I think the automotive radiators are a good suggestion. Even the wimpiest econobox car has an engine rated at 60hp. That means the cooling system has to be capable of rejecting approximately 60hp to the ambient air although it does not have to achieve ambient temps and it has a 60hp engine to drive the fan and water pump. Get a radiator for a heavy duty pickup truck, especially if it has an integral electric fan with shrouding. Then all that is needed is a 12VDC source.

1hp~9-12k btu.... i thought at least? I think air cooling would be best bet, for practicality

[Smackre]

I am pretty sure 1hp = 2500btu and 1 ton = 12000btu

But the place who makes that unit said it was a 24000btu unit.