Hydraulic Resevoirs

[Sawyer Rob]

I'm wondering if you have restrictive points that are creating more heat than they would if the oil was more free flowing... 90's and smaller capacity valves ect.., create a lot more heat that you have to get rid of...

My splitter it powered with a 30hp diesel, 20 gallon pump and a 15 gallon tank that I don't even have full, and I NEVER even come close to having heat problems!

SR

 

[J_J]

If he is using the relief valve a lot, the heat will build up .

 

[LD1]

I think you will be fine as planned. Pulling from one tank, returning to other. Just make sure you have plenty of flow between the two.

Your heat issue was simply lack of volume. 10 gallons on a 28gpm 2-stage is just way too small. That is the capacity of smaller splitters running 11gpm pumps.

 

[grsthegreat]

The prople that made my hyd tank say any use of it in summer would require a cooling fan unit. Its 25 gal tank.

In winter the outside temps will cool it, but in summer, no way.
And dang, those coolers are like 800-900 bucks

 

[PILOON]

Some food for thought.
A cooler is like a radiator, lots of tubing and fins to dissipate the heat.
What would be wrong with trying to use a small car rad (well cleaned) on the suction side of the pump?
Would that not work?
For that matter copper tubing comes in (usually) 25 ft coils, could a suitably guaged coil downstream from the engine cooling fan not do the trick?
Also a fan could possibly be rigged with V-belt and couple of pulleys to cool the coils or rad.

 

[IceStationZebra]

More to think about. I chugged the numbers and the 31 gallon reservoir gets you about 4000 BTU/hr of cooling with oil 100°F over ambient (assumes no wind or sun load). Go look up coolers and you will have a hard time finding one that small. Backs up what several of us have said - a larger reservoir just buys you time due to time it takes to heat the added mass. If it buys you enough time between coffee breaks great, otherwise it would be cheaper to increase the cooling or possibly decrease the system losses (which create heat).

Piloon has the right idea, but I do not recommend putting a cooler on the pump inlet. You want to keep the inlet restriction at a minimum to maximize pump life. It could cause a collapsed inlet hose and/or air leak resulting in cavitation.

The standard solution is to add an oil-to-air cooler, but you could use Piloon's suggestion of tubing, etc. Anything that increases the surface area, especially with forced air flow, will help. Scavenge a stand-alone transmission cooler from a truck and position it so the engine air blows across it. Most tranny coolers are rated around 150psi, but your mileage may vary.

The idea below will allow you to use a cooler designed for less than 28gpm. A company I used to work for did this on one of their off-road forklifts to avoid bursting the cooler in cold weather. I highly recommend the pressure gauge so you can monitor the back pressure with cold oil and adjust the bypass opening, thus preventing a failure.


ISZ

 

[oldnslo]

ISZ,
I have seen check valves installed to act as cooler by-pass valves in place of the flow control. This eliminates the need to fine tune the flow control as the temperature changes.

 

[handirifle]

Why not add something like a trans cooler from a car? That is designed for hyd fluid.

 

[kiotiken]

Thanks guys, you've all given me a lot to think about. I really like the idea of using the engine's air stream to cool a rad. I really have to give this some more thought at this point.

I have a couple questions about the rad. Could I use a rad between the tanks and have it gravity fed? I would go from the outlet of the first, smaller tank, through the rad at very low pressure and into the inlet of the second tank. If that is possible, could I then use an automotive rad since there would be virtually no pressure? I'll also look for a trans. cooler but may be more expensive.

I'll have to take a closer look, but I don't think I can get a pulley on the drive shaft of the engine, the pump and bracket are in the way. I don't know of any other sources of extra heat, I have no diverters, flow controls etc.

 

[Scooby074]

Having the two tanks will act like a baffle. This might help cooling as it will slow the oil. Youd have to make sure you have a low restriction path between the tanks though. Might be easier to just cut a couple large hole in the side of the tanks and weld them together as opposed to trying to run pipes between them

I think adding capacity will work out for you.

I know there is no love for PA right now, but they do have their ProPoint 26GPM cooler on right now for $349. 26 GPM Hydraulic Oil Cooler | Princess Auto Unfortunately it draws 16A. You might be able to swap your lawn mower battery for a car battery and get some decent run time, but I doubt your motors alternator will keep up causing more problems. An external alternator run off the motor could power the fan on the cooler, but again, its a HP parasite.

Sticking a fan onto the motor to blow across a rad will draw HP from the engine that you dont really have to spare.

I think right now your best bet is to just add oil capacity. I run my 22gpm 2 stage on a 18Gal tank with baffle. Ive yet to see the temps in my tank get to a level that concerns me. IT actually runs pretty cool.