Hydraulic Cylinder as track tensioner

[David Devuono]

Anyone have any experience using a hydraulic cylinder as a track tensioner. I am thinking that I can put a breather cap on one end and tap a cap on the other end for a grease nipple. Then i could maybe (using 6 in stroke, 1 " bore) pump it with grease, maybe leave an inch or so air gap. I see that many commercial machine use this and it looks like regular cylinders are used?

 

[Dirthog]

The only problem with that is you need a pressure relief in the system too or you will just bend the cyl if you are lucky or break something worse if you hit something

 

[Leejohn]

Cyl well work ok as long it's pushing on a super strong spring before the idler wheel. I would think the hard part is the guide for the idler wheel and holding the spring in place.

 

[J_J]

I would think a large threaded rod through the spring with an adjusting nut would keep adequate tension . A hyd cyl would require a valve of some kind.

 

[brain55]

How about giving us the whole story. What are you trying to build or modify? Grease cylinder track adjusters are typically rams where the OD of the rod is the same as the ID of the tube, not some spindly 1" rod in a 3" bore. More like a 2" rod in a 2" bore. Like was previously posted they also have some kind of spring loaded mechanism to absorb any shocks or excess debris in the tracks so they don't bend or break stuff.

Brian

 

[AKKAMAAN]

Air in the cylinder doesn't sound very good, air will get squezzed out pretty quick....I'd use a small pre-charged accumulator together with the cylinder....

 

[wdchyd]

I think what the OP is saying he may use a D/A Cyl and load grease in the base end and put a breather in the rod end....

It'll work but as Brain mentions this setup will be kinda whimpy as most track adjuster cyls are S/A with the rod dia the same as bore for strength....

Accumulator may not work as track adjusters sometimes need to stay put with some slack for track performance

I would think as far as a make shift T/A cyl, a small snow plow ram would be a better retrofit....

 

[Kernopelli]

Well, I'm watching Dave. I am getting ready to make a track system too for a hydraulic drive setup ~ somewhat~ similar to what you have. I'm trying to decide on your belt track system, buying an old snowmobile track/drive shaft & sprockets or a 100 pitch chain like was used in the Wheel Horse project posted recently. Leaning towards splitting a 20" sled track right now but whatever way I go, a tensioner will be required and I've been pondering it as well. I personally think the spring and threaded rod would work fine. I've considered motorcycle/atv shocks, then I remembered the old Fox air shocks and then I considered a cylinder too but thought about pneumatics for shock absorption rather than a rigid hydraulic system. Also looked at used snowmobile track tensioner parts on ebay recently for ideas....? I think the rod and spring is easiest so far.

 

[David Devuono]

Thanks guys, I know not all of you read all the different forums, or all the threads in Hydraulics. Build is takinig place in "build it yourself" Ride on Tracked Dumper. I considered the use of a hydraulic cylinder as that is what Cat uses in their small tracked loaders. Looks like a plain cylinder with a breather plug at one end and a grease fitting at the other end. No springs. Problem is with finding a small and strong spring. IE 280 lb spring did nothing to prevent my track tensioner from collapsing when I tried to move this around in the driveway. A spring and threaded rod might be tightened until the spring is fully compressed. As the tensioning wheels are mounted to a tube that slides inside a larger square tube, the cylinder will have no side loading and be pushing with about 500 lbs force so does not need to be large, thus 1 " bore.

 

[mmurphy]

My thought on this is, it should work also.
May have to do a few calculations on what kind of load will be pushing back on rams to decide what size cylinder to use. I may be wrong but, I do not believe you will have quite the punishing effect that a dozer would have on its components. I bet JJ, or others may have some figures on how to determine load on it.
Just make sure you have a way to evacuate the grease when needed!