Experimental Coal Vac

I have been dreaming of a way to move coal from my bin, to my hopper without filling buckets. At first I was going to use an auger. It turns out that my bin is a little to close to my hopper for any of the new grain augers I've seen.

I've seen a few guys on the forum using shop vacs and that got me thinking. Shop vacs are fairly expensive, a freind of mine was scrapping a propane hot air furnace and he let me have the blower for free. The blower is 1500 CFM-ish? 1/2 horse power. I was thinking this should be able to pull in as much air as a shop vac, and it's free.
I attached an old wall thimble to the inlet so I could put in a filter if needed. Then attached some stovepipe addaptors that we also laying around, to get it down to 4". I had a 4" flexable drain pipe and hooked that into it.

Then I built this out of 4" and 2" PVC. The idea here is to elimenate the need for the 5 Gal bucket from other coal vac systems. The 4" "Y" and "T" are used in shch a way to make it easy for air to get through but difficlut for coal to follow.
If it worked, the coal would come out here. There will be a flapper valve on the bottom to let the coal out.
This is version V1 and has been a total failure. One of the problems is the blower hook up. The squirrel cage is split in half, and I only have one side hooked in. Next I will hook in the other side. Also, I do need to re-think the plumbing.
I'm not ready to give up. I think this will require a few revisions before it actualy works.

-Don

Learning what doesn't work is valuable too. Try holding your hand over where the coal comes out to see if it will then work. I suspect it is losing vacuum there.

I doubt highly that the furnace blower will work for this application. Those blowers are designed to move air volume. They aren't designed for vacuum power. It's analogous to using 4th gear to climb a steep hill. But for the sake of the free blower, I hope you can prove me wrong partner..

And why such a steep climb? Is it to keep head room? That is making it hard to begin with

Dan has a little bit of hillbilly in 'em.

Franko,

That bottom part over the hopper gets covered when the vac is on. I have a trap door design in mind, but I have bigger problems to figure out. The cover was on during my testing.

Hotblast,

I wasn't realy trying to get a steep angle, But, I want a 45* angle going down. Since I'm not collecting the coal in a bucket I'm trying to use gravity to keep the coal from travling up the 4" pipe and into the vac.

Lightning,

I realized after building this that I need to hook up the other half of the blower, It may pull some coal then, I hope.

-Don

davidmcbeth3 wrote:Dan has a little bit of hillbilly in 'em.

Don...mispelleded .. appologies

No worries DM3, a lot of people call me hillbilly these days. Ironicly, these days I live in the flatlands!

I did a few revisions. I'm waiting for the glue to dry on the lastest one now. I will post photos in a little while. It might work?!?!?

-Don

StokerDon wrote:I did a few revisions. I'm waiting for the glue to dry on the lastest one now. I will post photos in a little while. It might work?!?!?

I'm on the edge of my seat with anticipation, Brother!

I did a revision yesterday CoalVac V2. Taking the tip from Hotblast that I might have been trying to "lift" the coal to high, I shortened the first piece on 2" off of the "Y" to about an inch. This dropped at least 2 feet off of the hight of the coal travel. Then I did a little A/B test, swapping between the blower and my 4HP shop vac. The shop vac won hands down. So for the next revisions, we will be using the shop vac.
This setup still didn't work. It moved a little bit of coal but that was it.

Last night I took myself to school in the "Coal Vac" section of the forum. I decided to incorperate an idea that "Wiz" is using, the snorkel. I put a hole in the end of the pipe that goes into the coal, glued a PVC 1/2" 90* in the end, then attached 5 feet of 1/2" pex to it.
This is revision V3. This does actualy pull coal up into the 4" vertical PVC pipe and out the bottom into the hopper. The problem is it only does it on the first try. Once the 2" pipe is full of coal and you shut it off and then turn it back on again, no coal moves.

So I guess it's back to "Coal Vac" school again!

-Don

I found the 6hp was the smallest that would work for me. I think Wiz ended up with two shop vac's providing the power for his but I don't remember his hp ratings.

edit to add, I don't have any vertical lift in mine. the pipe from my outside bin to the top of plastic barrel is horizontal.

Don
You might have better results using 1-1/2" electrical conduit and long sweeps for tour coal intake.
I have an 8' vertical lift and approximately 30 ' horizontal run with three 90 degree sweeps from my coal bin to the storage barrel.
The short elbows wore thru pretty quick but I was able to transfer a little over 6 tons last season before wearing thru the one sweep.

I also upgraded mine last season with a 6 hp craftsman vac from the older 5 hp I started with.

Still getting the bugs out of my ash vac removal...lol.
Paul

Don
+1` on using conduit and sweeps instead of pipe fittings.
The tighter the bend the more restriction and resistance to flow it has.
Any material with sharp edges will in time wear through the outer radius of a bend also. I have plated up the outside bends on schedule 40 6" steel elbows to extend their useful life. I have seen them worn through from corn and wheat being pulled through them.
Steel EMT conduit will last longer than PVC will but is more expensive for the initial purchase.
A friend has a dust collection system in his wood working shop that he built out of EMT conduit with compression type fittings. He sealed them with Clear RTV silicone after the system was installed. It has worked fine foe his sanders and small chip producing machinery but his big planer still runs of a stand alone system as the 2" EMT will plug up with the larger chips.
Dan.

I am no engineer train or otherwise but, I don't think the vacuum moves the coal. Rather I think the air rushing into the low pressure area "blows" the coal in.

That explains why the system stopped working when the pipe started to fill with coal an restricted the incoming air. It stopped because there wasn't enough air "blowing" the coal.

I think you would be better off to use a auger.

Yes I agree with Carl, there needs to be a flow of air to carry the coal. Don't give up on it partner. you just need the right ratio of air and coal for it to flow. It can work..