Hydraulic rock splitter

[blakester]

Awesome thanks IO, I'll check those out. If the manuals for the commercial ones are not very helpful then there is no need to upload them.

 

[blakester]

yeah the design looks to be simple, I'm still confounded at the price. It seems like a critical part would be where the counter wedge hooks into the cylinder so as the main wedge goes down it doesn't want to just push the whole assembly up instead of the wedge down. I feel like this is a build able tool with what I have lying around. Plus building = fun sooooo :dance1: In any case I'm going to go ahead with designing it either way.


.

 

[blakester]

OK so first pass at the wedge attachments. Th jinking about it more it seems like the wedges either need to slide or bend as the wedge goes down. Bending seems like you are asking for failure, unless you buy the wedges. I'm not sure if the commercial ones have wiggle room to accommodate the wedge inside the cylinder or not, will need to investigate more. So in the image attached, I though i would explore the sliding option. Because it's a round shape i would mount the ram inside as a sheath, i thought it would be better to have a box shape welded to the bottom to allow enough room for the wedges to move. Depending on the starting point, the counter wedges could need to move up to maybe 5/8 on either side. SO basically I would take a large square stock, cut holes in the top for the cylinder and the bottom for the wedges, insert some bar stock in the corners as shoulders, and then weld that whole assembly to the cylinder. It's rough I know but you gotta start somewhere.

 

[iointerrupt]

Yup, that's pretty much where I had went with my design. The counterwedges would just rest inside of some holder, free to slide about, as the main wedge pressed on them.

If you watch this video, you can see an actual splitter doing that: DARDA hydraulic Rock and Concrete Splitters in action - YouTube

This is what I had so far for mine:



Assembly bolts to the front of a tie-rod hydraulic cylinder, the main wedge gets pinned to the rod of the cylinder. Counter-wedges would be T-shaped like yours, and rest on the bottom plate. Big piece of pipe contains the primary wedge when the rod is retracted.

 

[blakester]

yeah interesting. Im encouraged by the the fact that our methodologies are in line, hopefully it means I'm not way off track. The next question for me would be this. I would like to use the hydraulics from my mini cat20 excavator. Im not sure of something however. Do all the cylinders on a machine get the same pressure and flow rate, with the possible limiting factor being the pipe size? or would the thumb say get less pressure than the boom arm in the line itself?

 

[iointerrupt]

I'm going to say it depends on the machine. On my Kubota KX41 the auxiliary port is actually variable flow rate (4GPM or 8GPM). The relief pressure on it is the same as the rest of the machine (3000psi), -but- there may be an individual relief valve for it that is adjustable. Most machines are complex enough to have multiple relief valves and multiple pressures throughout.

But out of the box, I'd expect the thumb to operate at a similar pressure to the rest of the machine. A pressure gauge attached to a fitting to test it isn't terribly expensive.

 

[blakester]

hmm, yeah ill throw a gauge on there and see what's up.

 

[Industrial Toys]

I have bought four (so far) hydraulic hand held breakers, of varying sizes, cheap at auction. Like $100.00 cheap!) Some made by Stanley. Workers don't seem to like them because they are so damm heavy. Maybe one could mount such a thing to the hoe. I see when they have hoe mounted ones, they not only hammer but use the chisel to pry and I'm not sure a hand held tool could withstand that.

 

[rosso1000]

It does seem easy

 

[Winmac]

Reality is more like this