Chip Compacter

[JPMach]

Has anyone on this board made their own chip compacter or briqutter?
I keep thinking about making something with a big hydraulic cylinder and a feed auger or something just now sure how to make it run automatic and such. The main reason for me would be to reclaim some coolant and have easier storage of large quantites until I go to the scrap yard where I could hopefully get better price for the chips.

I checked into the price of one of the comercial briqutters and their smallest one cost like 50 grand. It just seems like something a bunch of us could collaborate on and come up with a cheaper alternative that we could build in our own shops and use ourselves.

If anyone has some ideas I would appreciate hearing them.

JP

[HuFlungDung]

JP,
I've wondered the same thing. I've got barrels of aluminum milled chips sitting around waiting for the reluctant traveller (you know the type) to come around and offer me a pittance for them.

I was thinking of something like a man sized bolt action chamber, with the end of the hydraulic cylinder ram always engaged, and feeding the chips down through the slot for compaction.

I wonder if a person could rely on the taper of the 'barrel' on this thing to provide enough restriction that you would get decent compaction after the slug had passed a couple of feet through. Maybe one would have to block up the end initially to get compaction started. After the barrel was full, and reasonably tough to move, further compaction would take place on top of the existing slug.

The resultant chip slug would come out like core, I suppose, or it might break off by itself in reasonable lengths.

[Geof]

This is something I pursued for a while and as JP says discovered the cheapest unit is in the 50k region. I did some experimenting with a 30 ton press and made some pucks around 2-1/2" OD and about 5/8" thick getting a compaction ratio of about 8 or 10 fold, I can't remember exactly. The coolant recovery was impressive; about one fluid oz from the 30 cubic inches of loose chips I put into my trial compactor. I calculated I am throwing out 10 gallons of coolant with every cubic yard of chips.

I also did a lot of Googling and found a German company that made a compactor that works a little bit like Hu's suggestion. It was a two stage system where the chips were augered down into the 'bolt action' chamber with this stage giving about a threefold compaction. Then another ram came in at right angles in the chamber and gave another fivefold or so. The forces needed are quite impressive. I think the German machine was working at 300,000lbs on the second stage ram. The hydraulic pressures needed for these things were high; 5000 to 7500 psi I think and this probably is most of the reason for the high cost.

I wondered about making something using a low precision but high force ball screw driving a wedge system to act as a force multiplier but put the idea on the back burner because I did not have the time.

Then I was talking about briquetters and coolant recovery to a coolant salesman and he mentioned that sometimes the compacted chips are worth less to the recycler than loose chips. The reason he gave was that the briquettes cannot be top loaded into a furnace which already contains molten metal or is already hot. The reason for this is that they still contain trapped coolant which is mostly water and this can cause a very nice steam explosion. The furnace has to be designed for taking briquettes and have the ability to have them loaded from the bottom. I still haven't pursued the idea any further but before doing anything else I will find out about the furnace thing and check with my recycler first.

[JPMach]

I have thought about that same type of machine. Similar to how a square hay baler works. I too figured on just having a hopper above a port where a large cylinder would just work back and forth. You could set it up on limit switches or pressure limits or both I suppose. I would think when the ram retracts that the chips should fall into the chamber by gravity but I have thought about an auger of some type here also that could even pre compress the chips slightly.

Somewhere in the "barrel" there would need to be some small holes or slots to allow the excess coolant to drain out, or maybe back through the ram into a pail.
I would think that the compacted chips would break off into sticks a couple inches long or so unless you could generate high enough forces then it maybe longer.

I would like to see the scrap man run his magnet across these big slugs and find one or two slivers of steel. He always seems to in a barrel full and then cut the price down on me because it is soooo contaminated.

JP

[JPMach]

In reply to Geofs statement, I too tried some in my 20 ton press. If not pressed soo hard then it simply compacts the chips yet they still will fall apart, the harder you force them then they start to form pucks. I would think you could pack them enough to reclaim some coolant and save room in the chip barrel yet still be basically loose in the barrel. A good shake of the barrel and the kind of break apart yet are flat instead of curled.

JP

[JPMach]

Ok I had a thought.
I agree with Geof's statement about checking with the recycler first to see if they will pay you more for pucks or not but I would at least like to know the machine could be made and apporximatly how much it would cost to build so that I can figure out how much better the recycler would have to pay me in order for the machine to pay fo itself in a couple years.

My though was this, in going along with Hu's idea and kinda of a long the lines of a square baler have a square hole that is straight for about maybe 8". This is your compaction chamber. Make the square hole by cutting a slot in a piece of steel and bolting another piece ontop of it. The still have the slot in the bottom piece of steel and make another piece of steel that would fit down inside the slot and pivot back towards where the straight section stopped, make this piece maybe 12" long. Then put a die spring or two on the far end of this to hold it down. When the chips start out soft it forces the "barrel" to have a small hole in the end and then as the chips get more and more compact it opens up a bit and holds tension on the slug (just like a square baler). I would think I could mount a 6" cylinder I have laying around with 8" stroke on the end (could easily run 2500psi and have 35 tons of force)and rig up some sort of loading unit to fill the chamber and then extend the cylinder, retract and start over. The whole thing could be run with just limit switches and timers no plcs involved. The most expensive part would be the hydraulic power unit to run the cylinder, but should be able to find something at the junk store that would work. If the slugs being to hard was a problem you could mount some sort of rotating arm on the discharge side to keep breaking the slug up as it came out, would still have nice flat chips though.

Probably from about the middle of the straight section of barrel to several inches into the taper put some holes or slots in the barrel to allow the coolant to come out.

The little test I ran in the shop press gave me about 85% reduction in volume of the chips. The coolant didn't squeze out until the last bit was pressed but there was alot of coolant in the little bit of chips I tried.

JP

[Geof]

I had a thought about your thought

You don't need the complication of the die springs and the variable aperture compacter section. This is only need for starting the plug of chips and is redundant after that. Have a sliding gate that blocks the bottom of the compacter and compact the starting chips against this. Once the system is filled to the top of the tapered transition pull the gate out; actually it would be necessary to have a hole in the gate the same size as the bottom of the compacter barrel and just pull this hole into alignment. Once started there is little reason to completely empty the compacter and actually it would be difficult to do that without pulling it apart.

Make the compacter cylindrical so the chips are compacted symmetrically in the tapered transition. The top can be heavy wall tubing, the bottom the same and the transition machined from solid with nice smooth curves going from parallel to taper back to parallel. The pipe sections would fit into counterbores at each and everything held together with long bolts. The transition section is going to be subject to wear so it might be nice to have it easily replaceable and also it could possibly be hard chromed inside.

For the pump get hold of a large swash plate pump. Something from a large tractor with a hydrostatic transmission might work. The advantage of a swash plate is that you can inversely vary pressure and volume flow so for the early stages of compaction your piston would move fast and then as more force was needed the pump would respond. It might even be possible to have a closed system if the pump was reversible. In this case an accummulator would be needed between the return side of the cylinder and the pump to compensate for the rod displacement.

I wish I had the free time to play with this idea. If you decide to do something and do choose to make it cylindrical I can machine the tapered transition provided it is not more than about 6 inches OD and 8 inches total length. Although longer would be possible in sections that would screw together. I have no idea what form the taper should be and would probably start with something like 5 inches going down to 2 inches at a 60 degree included taper and see what happened. Also for a proof-of-concept prototype I would replace my sliding gate suggestion with a solid screw on cap and a screw on cap with a hole to match the lower tube and just thread the OD of the bottom tube.

[JPMach]

For the pump you could accomplish the same thing with a much cheaper two stage pump. That is high volume low pressure and then low volume high pressure ( also called a log splitter pump).

As for the size of the chamber I would think that if you started with about 3" diameter and then tapered down to 1" diameter this would keep the size down where you could run it with a 6" cylinder running 2000 to 2500psi which again is cheaper to operate. Running those size pipes would also give the approximate required 85% reduction in volume. I agree the the taper section should be hard chromed but at the very least if you were only going to run aluminum it should be made out of a tool steel.

I would think just a cap that bolted on the end to get the plug started would be enough, shouldn't need a sliding gate at all. I think I might work on turning up some pipe to make the chamber over the next several weeks on my manual lathe and then try running some chips through with my shop press before worrying about a power unit and cylinder. Shouldn't take much and then I would have something to take to the recycler to show him what I mean by pucks to see what kind of price he would pay.

I still wonder what the best way will be to allow the coolant to come out. I am thinking just a loose fitting plunger and maybe have the whole unit at a slight up hill incline.

If I do make anything that works I will make up some general prints of waht I did and post them as well as some pics.

JP

[Geof]

Yuor pump idea is more practical; I was getting carried away, same thing with the cap.

I think with your 3" to 1" taper you will probably get more than the 85% reduction. Your piston has to work only in the parallel 3" bore above the taper so there will be some axial compaction here; then this already compacted material enters the taper where it is radially compacted further. The axial force need to drive it through the taper has to be transmitted through the compacted material. If it is too compact before it reaches the taper, or if it gets too compact before it exits the taper it will jam up in a vicious circle. The more its is axially compacted the more force is need for the radial compaction which means the axial compaction increases, etc, etc. It might be tricky finding the correct balance between the two stages.

[JPMach]

Ya you're right but if you start with smaller taper you can always bore out a straight section in the end of the taper. I would then make the barrel out of two sections of pipe the first withthe straight in it and the the piece with the taper with a little bit of straight on the end but built to accomadate opening up the last bit of straight section.

The reason I said 3" is that I just figured if you start with around 3" to 4" diameter stuff instead of 6" that it would again be cheaper to build the required pressure system. Would still have to work on the feeding mechanism though. I am kind of thinking about a Y in the first section with a auger coming into the chamber at the slight angle. This would then fill the chamber and if you ran the system with a small plc you could have the auger run until it cam to a certain amount of torque to precompress the chips (this would further add to the total compression and therfore probably require opening up the end some more). The auger could the go up into a hopper for the chips, then shaft of the auger could go through the other side of the hopper and allow mounting the motor outside of the hopper.

I can actually see this thing working in my head but its just a matter of working out the kinks and deciding how much it would cost to build. It might not do the 200 pounds per hour that some of the commercial models run but if it would run more than 50 pounds I would be completly happy with it.

My dad also want to use the same press for pressing oil out of soybeans or canola in order to make biodiesel so it may really payoff. For this I think I would simply have a second barrel to swap in so as not to have to remove the chips from the first. This second barrel could be identical to the first with the addition of a heavy duty "screen" on the end or another section of taper barrel down to an even smaller diameter.

JP

[Geof]

......My dad also want to use the same press for pressing oil out of soybeans or canola in order to make biodiesel so it may really payoff. For this I think I would simply have a second barrel to swap in so as not to have to remove the chips from the first. This second barrel could be identical to the first with the addition of a heavy duty "screen" on the end or another section of taper barrel down to an even smaller diameter......
JP

Ah, now the real motivation comes to light . This could be very practical especially if you have surplus crop or some that does not meet the standard for sending to market. Make the canola crusher first and then use the money you save from that to buy a commercial briquetter.

On a side note I have a Dodge Sprinter on order; maybe I should be looking at biodiesel.

[JPMach]

Ok after thinking about this for several days now, I don't like the tapered barrel design. I can see to many possible problems with it being:

1. Extreme wear on the tapered section. A straight barrel with a sliding gate on the end would compress the chips as well as, but should have a lot less wear.

2.I am not sure that the tapered barrel would even work for chips under such high compression. I kinda of think that without the exact right size taper the slug would move out and the chips behind wouldn't be compressed as much which would then slide out easier which would then allow the next shot of chips to be compressed less yet.

3. Assuming one did find the exact right sizes to make the tapers, what happens when you run different chip materials through or even just different size chips?

Looking on the internet I did come across a short video of one of the commercial models working it is at http://www.prab.com/briquetting%20sy...riquetter.html toward the bottom of the page there is a link to the video.

I really like this design better as it first lightly compress the chips with a small cylinder which forces them over into the main chamber and when fully extended closes the main chamber up tight. Then the larger cyclinder extends and makes atight puck, after which a sliding gate opens and the cylinder extends a little more and ejects the puck. This design should have less wear than a tapered barrel design and should work with and material or size chips you put in, the only difference would be the length of the finished puck. The only down side to this design that I see is two more small cylinders and a plc to control it would be really nice.

I also noticed researching these on the internet that almost eveyone says the pucks will bring more money from recyclers as one the coolant is pretty much gone and two more of the aluminum melts in the furnace instead of turning into slag which happens to most of the chips that get dumped in.

On another note I think this exact same press could be used to extract oil from seeds to make biodiesel. You would just get very large "pellets" of dry matter out, which then could be tossed in a grinder mixer with corn to make cow feed or possibly could even be burned in a stove.

Let me know what you guys think. It would be a while before I ever got around to making one but I could start desining it out and getting some parts when I stumble on them.

JP