AA 130 Outfires.. Coal Feeding Problems??

LsFarm wrote:You can make a screen using 1/2" 'hardware cloth' it is a welded screen.

Ok, will look into that in the next day or two. Only question to ponder is where to find it in less than 100' rolls.

I also saw something else today that I think might be contributing. If you look at the photo of the bin, the end of the tube is in there... somewhere... you can barely see the end inside the dark square. The floor above the end of the tube is hanging over the tube like a shed roof. I'm thinking this area should be cut out so the coal will sit directly on top of the 2-1/2" of tube that's supposed to stick out of the doghouse.

I bought this bin from a friend who has used it for 2 years without any trouble. His was inside and I don't think his coal has near the fines as I seem to.

Today I made a tool to clean out the end of the tube without having to shovel out the bin.

Tom

Here's where I stand.

I'm trying to find a small piece of hardware cloth (less than a 50' roll costing $150+). I think I located some last evening that a friend has left over from a corn crib project but that material is weeks away. (He lives 4 hours away). I've searched and called and searched some more and cannot find a source for this type of material in less than 50' roll.

I've managed to work up a routine with the boiler. It lasts about four hours before the fire is at risk of going out. I make a point to visit every four hours and run my new tool down the feed tube to clean out the very end which is always packed solid. I then add a little coal through the transfer head to play "catch up" as it's typically behind at this point with feeding coal.

What I'm studying right now is options to solve this problem without screening the coal. I think that is my short term solution but in analyzing the problem I don't really know if this would solve it altogether. the fines are "sticky" only at the bottom of the feed tube. I've not had a build-up anywhere but right at the bottom. Why? This being a used boiler and I'm guessing is about 40 years old, the feed tube wasn't in like new shape. the very end of the tube was a little rusty and was also plugged when I removed it from the seller's coal bin (I think this is why he gave up on it). Could the rust at the end of the tube be causing the fines to stick instead of sliding their way up the flights of the screw? I'm very suspicious of this.

Also, tonight, I'm going to clean out the bin (again...) and inspect the end of the tube. The question to be answered is this. Is there a gap between the pipe (or the outside of the feed tube) and the flights of the screw? This could cause the fines to bypass and collect at the bottom until there is enough that not coal rocks can enter.

Another thought I had was to add a half of a flight to the end of the flights extending out of the coal tube to "reach out and grab" the coal nuggets. If there were more coal nuggets traveling up the tube would this help the fines to push further up the tube where there is no plugging problem?

What do y'all think? This thing is kicking my butt royally! I've had a gutt full of getting up at 2 in the morning to hand feed this pig. This is a good unit. I just need to get past this one last problem... this is all that's keeping me from shutting her down for the winter.

Does anyone have a pic of a new feed tube and what the end that's in the bin looks like? This might help.

Tom

Take an adjustable wrench and bend the end of the flighting out so it extends at least .5" outside the end of the tube. Then take a grinder and make sure you have an angle on the end, kind of like a lawn mower blade except not sharp, just angled. This will enhance the action of the auger in the pile.

U235a4 has a new auger on the unit I sold his folks, maybe he can snap a pic, I do know ther eis no angle on the new ones, but from expereince I have found that the angle helps coax the coal up the tube.

I have had a similar problem with my AA130. Have had the wet coal issue the last few days. I think the solution is to heat the bin to dry the coal.

The pic I have of the end is too poor to post, but I can tell you that from the factory the flights stop at exactly the end of the tube. Here's a pic of the doghouse. Just want to make sure you have the correct shield in it. It hit me that perhaps your auger is not being held up off the floor by 4 or 5". The shield does not hold it up, but it helps position it correctly. What kind of coal are you burning? Maybe try a few bags of different coal?

I'm amazed that you don't have a 'local hardware' store that will sell the harware cloth by the foot.. But that is the way to go, screen the coal..

In the mean time. I'd follow Matthaus' suggestion, it will certainly help, and won't harm anything..

Freddy's idea is also valid,, my auger ends about 3" above the floor, leaving room for the fines to settle there, The fines will always settle to the bottom, the coal is in constant but slow motion, the fines are like sand slowly sifting throught he coal to the lowest level.

I just loaded 1500# of coal into my hopper from my tractor's front bucket, I fill the loader, then transfer the coal to the hopper with 5 gallon buckets.. after transfering all the coal, I only had a handfull of fines in the loader bucket.. So my coal is pretty clean. It flows like ball bearings it's dry and clean.. What little fines I have don't cause any feeding problems..

I do have the last 1" of my flighting bent out like Matthaus suggests and I'm sure this helps some..

Greg L

Matthaus On: Wed Jan 14, 2009 10:17 am

Take an adjustable wrench and bend the end of the flighting out so it extends at least .5" outside the end of the tube. Then take a grinder and make sure you have an angle on the end, kind of like a lawn mower blade except not sharp, just angled. This will enhance the action of the auger in the pile.

I did this per a suggestion from GregL about a week ago. I didn't grind the end of the flight, but from years of service, it was worn almost to an edge.

Freddy, The doghouse used in this bin is the factory doghouse. The installation was made with the bottom of the boiler being at the same elevation as the bottom of the doghouse. The tube is sticking out of the doghouse by 2.5" (about). The end of the tube is up off the floor of the bin by about an inch. this is different than what you describe. I also think the end of my feed tube is missing some material. The end of the screw flight sticks out about an inch (not flush like yours). Not sure how this would impact the feeding of fines/nuggets but I know it's different than your new one.

I talked to a friend today who has his boiler disassembled and out of service while moving. I'm going to borrow his feed tube and with a 30 minute swap-out a lot of questions will be answered. He also said that last winter his coal was sopping wet and would take days to stop running all over the floor after filling the bin (the same bin I am now using). He had no problems with plugging. He used this bin for two years prior to me buying it from him this past fall. the set-up is exactly the same as mine except his feed tube is in better shape than mine. He also had fines but not near as many. at the end of the season, he would clean out the coal bin and also clean out the fines that collected under it.

Thanks for the input.

By the way, the parts came in from AA. I plan to install the agitator tonight. Is this going to make my problem with the fines worse?... by further shaking the fines to the bottom of the bin?

Tom

LsFarm wrote:I'm amazed that you don't have a 'local hardware' store that will sell the harware cloth by the foot..

Of 4 or 5 local hardware stores in a 25 mile radius from me there is only 1 that will cut hardware cloth to your needs. This store has been there since the late 1800's when this area was an oil boom town. The others only sell it in 50 or 100 foot rolls, I don't remember which.

Finally found one this morning. There's not much in Gettysburg as far as hardware stores. But I haven't lived here very long and after asking around at work again today I found a off the beaten path hardware store in a neighboring town (cash only sales...). They cut it by the foot.

will stop in there on the way home.

Tom

Hi Tom, the distance that the auger is off the floor is determined by the support bearings on the gearbox bracket, the doghouse does little more than provide a shield for coal, I am operating mine with no end plate and it works fine (no pun intended ). If your auger is only 1" off the floor you can alter this by shimming the boiler up off the floor, especially if you angle it ever so slightly back. In fact you might have a lower than usual auger for that very reason, have you checked to see how level the floor is from the boiler to the bin and how level the boiler is? Ideally you should have more than an inch between the end of the auger and the floor of the bin, my experience is that they are usually at least 2" if everything is level.

Matthaus wrote:and it works fine (no pun intended ).

Thanks for rubbing it in...

I see that there are some things I need to look into but raising the tube off the floor of the bin is major design change to the bin. I need to try some of these other things before diving into major changes.

This bin worked previous in the same configuration. The only differences being the coal has more fines and the end of the tube (mine) is a little rusty from being old.

The factory dog house is a shield for the anthratube. The coal is supposed to fall into the anthratube at the end of the dog house, with no weight on the anthratube.

gregolma wrote:The factory dog house is a shield for the anthratube. The coal is supposed to fall into the anthratube at the end of the dog house, with no weight on the anthratube.

Yes and the coaltube sticks into the bin by 1/4" so it does receive some small load from the weight of the coal pushing on it. Mine has an end plate that allows coal in around the tube but shelters it from the load on top as the manual depicts.

: Freddy On: Sun Jan 11, 2009 10:28 am

Are you using the factory dog house? The auger extends past the end shield 2 1/4"?

Matthaus On: Wed Jan 14, 2009 3:51 pm

Yes and the coaltube sticks into the bin by 1/4" so it does receive some small load from the weight of the coal pushing on it.

so... which is it? 2 1/4" or 1/4"? I set up the bin/tube/dogbox according to what the old book said and if I remember right (don't have the book in front of me) it said 2 1/2"

I know these are subtle differences but could make a big difference to the operation of the unit.

Tom

Here's the auger end before I did my install.