Help with an auger feed problem!

Help with an auger feed problem!

PostBy: stovepipemike On: Mon Jun 23, 2008 9:04 am

I have a small Anthra-Heat stoker [5" vent connector] which has done the job for the past two winters.It holds about 60# in the hopper and I use pea coal in it. The problem is that the auger which rides in the lowest part of the hopper in its own little boxlike enclosure can trap a piece of coal between it and the sidewall.It has a gear reduction motor which does not stop.The result is that it starts to move the entire hopper slightly downward under the pressure until the coal snaps.To anyone mechanical by nature this sound sends up the red flag that trouble is in the making.This crunch and snap can be heard up in the living room and will result in an unwanted consequence unless I can modify the design. I thought about trying to fabricate something over the area where the "rubber meets the road" so as to eliminate the pinch point. Then I reasoned the new "skirt" would only move the crunch zone on to the new member. I do not want to hand fire this little piece because the firebox is only a small one.I do not know how to get pictures on the screen or I would be glad to do so. Can you help with an idea? Thanks for your help. Mike
stovepipemike
 
Stove/Furnace Make: Keystoker
Stove/Furnace Model: KAA-2

Re: Help with an auger feed problem!

PostBy: LsFarm On: Mon Jun 23, 2008 9:09 am

Is this the little boiler that as the auger feeds, the grate shakes at the same time?? Matthaus has one, that is not in use right now,, maybe he can look at his [when he finds time] and make a suggestion.

What will help, is to make sure the auger to 'anvil' is a shear action on the piece of coal,, not a crushing action. The coal will shear between two sharp edges easier than it will crush between two surfaces.

Greg L.
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Re: Help with an auger feed problem!

PostBy: Richard S. On: Mon Jun 23, 2008 9:35 am

Is it an auger we are talking about here? The augers on the boilers have a shear pin, it won't prevent it happening but it will prevent any damage to the machinery because the pin will snap before anything else. That's pretty standard on any type of machinery that can jam.
Richard S.
 
Stoker Coal Boiler: Van Wert VA1200
Coal Size/Type: Buckwheat/Anthracite

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Re: Help with an auger feed problem!

PostBy: Matthaus On: Mon Jun 23, 2008 10:42 am

I believe you have a Mini-Stoker 80 designed as a supplemental heating unit for oil or gas fired hydronic boilers. They were made by Anthraheat in Emmaus PA, but regrettably are no longer in business. If you are running the unit during the summer to provide DHW then taking it off-line for inspection and cleaning has to be planned for, otherwise I would recommend a full tear down and inspection/cleaning right away. Take a careful look at the cam that moves the grate shaker arm, check for cracks, wear and other signs of duress.

The unit should not be crunching coal, there is ample room between the auger and side wall in the transfer box to prevent any interference. I posted a pic of what yours might look like if it is indeed a MS 80. I would check the size of your coal against the sizing chart to verify that it isn't oversized.

If that is not the issue then I think the snapping noise is coming from the cam, mine was broken when I got it and you can see by the design that if the springs are too tight an obstruction in the grates will cause all kinds of mechanical mahem (the adjustment on the springs in the grate shaker arm are meant to absorb stuck grates and protect the cam). I am in the process of installing a solenoid to move the grates to eliminate this problem. By design the shaker runs anytime you are feeding coal, a jam will cause the gear motor to exert all available force to either break the mechanism, compress the spring, or free the jammed grates (again this depends on how tight you have the adjusting nuts on the spring). In the manual it states that some hand shaking will probably be necessary to properly remove all ash under the fire, so maybe you need to give them a little shake every once in a while to see how free they are and to verify sufficient ashing.

Keep us posted on your findings.
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top view of auger transfer box that the hopper bolts on to
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Matthaus
 
Stoker Coal Boiler: Leisure Line WL110 Dual Fuel, natural gas
Hot Air Coal Stoker Stove: Leisure Line Lil' Heater (rental house)
Coal Size/Type: Rice and Buckwheat Anthracite

Re: Help with an auger feed problem!

PostBy: stovepipemike On: Mon Jun 23, 2008 7:29 pm

Matthaus ~ I think you are absolutely correct about the stoker I have. It was made in Emmaus,Pa. I could not get any info on it .It does not have a manufacturers badge of any sort,only Anthra Heat Emmaus,Pa.on the loading door.I was really hot to get a manual and find out all about it before i installed it.a kind gentleman @ EFM put me on to a person that used to work for Anthra-heat. That person did not know much about it since he did the deliverys to the basements but not the installs.He did remember that they tended to have ashing up problems if the operator wasn't careful with them. I went with pea coal because that is what this man told me they used as he remembered. He told me that the owner passed in the 90's and his widow had just pased. End of the line. Are they indeed supposed to use pea? That would be important information to know because it is time to buy some coal right now. The auger from the gear motor drives so hard that the lovejoy coupling crushes and squeezes the composite element out from between the members. I have a band around the joint to keep it from misalignment. Your picture shows the box just as I have and I keep studying it and have to conclude that the crushing happens at the round boiler tube as coal pushes thru immediatedly ahead of the firebox. I have found out that it is very important to drop the spring rod from the grate shaker lever and manually shake it each morning. My next question would be what should I be looking at now to round out this dilemma? Thanks again, Mike
stovepipemike
 
Stove/Furnace Make: Keystoker
Stove/Furnace Model: KAA-2

Re: Help with an auger feed problem!

PostBy: Matthaus On: Tue Jun 24, 2008 12:48 am

The manual states that Buck Wheat or Pea sized coal can be used, so try some of that and see if the issue gets resolved. One other thing you might try is to unhook the ashing rod and manually ash it for a day and see if it still makes the noise, I am still thinking that the noise is coming from the ashing mechanism. Also check and see if the coupling is crushed and under strain when pushing coal and not driving the ashing cam and lever, my guess is that it will not be. :)
Matthaus
 
Stoker Coal Boiler: Leisure Line WL110 Dual Fuel, natural gas
Hot Air Coal Stoker Stove: Leisure Line Lil' Heater (rental house)
Coal Size/Type: Rice and Buckwheat Anthracite

Re: Help with an auger feed problem!

PostBy: stovepipemike On: Tue Jun 24, 2008 7:07 am

Thanks for all of the advice.I think now is a good time to take the little stoker apart to examine all parts for fit ,condition, and play.I never thought to try buckwheat because sometimes the pea coal slips around the outside edges of the grate and I falsely concluded that pea coal was as small as I should use.The coal yard in New Holland has buckwheat and I think I should get some of that and lock up the timer and let a half hopper or so feed continuously thru into the cool firebox to see what it does after reassembly.I"ll post the findings as I go and ask my son to try to teach an old dog AGAIN how to work this electric camera so I can post a picture documentation. Regards, Mike
stovepipemike
 
Stove/Furnace Make: Keystoker
Stove/Furnace Model: KAA-2

Re: Help with an auger feed problem!

PostBy: stovepipemike On: Mon Jun 30, 2008 8:12 am

I have disassembled the coal feed portion of the boiler.What I found was this : Feed tube I.D. 2.465-- Auger O.D. 2.070 that is almost .400" of difference,I suspect my auger might be worn out but I do not have any background in auger feeds to know. Also the hole [shaft support] thru the auger box where the auger shaft passes thru on its way to the motor is worn into the shape of an egg. The shaft size of the auger is .625, the egg hole at its widest dimension is.821. This area never was fitted with a bearing of any sort,simply shaft against metal plate.The shaft of the auger has a deep groove worn into it from the binding that was going on. The way this unit was assembled the shaker cam has no keyway pulled in it.The keyway in the auger shaft was ground in with an abrasive wheel [not broached] and is useless since the sides remain rounded.The drive Lovejoy connection has a keyway but no attempt was made to use a key. The soft element in the center of the Lovejoy connection was crushed apart [again]. There you have some preliminary findings. It looks to me like I better get movin' on the fix . I feel the cool breezes of fall on my shirt collar before I figure out where on earth to get an auger spiral twisted into shape and a bearing support for the shaft/coal box fabricated. As soon as you get an idea about any of this,please pass it this way. Thanks , Mike
stovepipemike
 
Stove/Furnace Make: Keystoker
Stove/Furnace Model: KAA-2

Re: Help with an auger feed problem!

PostBy: Matthaus On: Mon Jun 30, 2008 10:40 am

The diameter of the auger is about right, what to look for is the edges of the flighting, are they sharp or square edged? If sharp you need a new auger or replace the flighting (here is a source http://www.lorenzomfg.com/augers.html ). A weld shop should be able to repair your existing auger if you are not equipped.

The support of the shaft can be easily repaired by bolting or welding a piece of angle steel on the side of the auger box below the shaft and installing a pillow block bearing to support it. Then sheet metal should be sufficient to repair the hole around the shaft. The lack of keyways and the use of cobbled set screw holes to prevent spinning of the various pieces is evident on my unit as well. I would take the entire assembly down to your local bearing/drive supply house and see what they have to fix your issues.

Keep us posted on the repair, I have a feeling you will not hear any more snapping noises once you take care of these issues. :)
Matthaus
 
Stoker Coal Boiler: Leisure Line WL110 Dual Fuel, natural gas
Hot Air Coal Stoker Stove: Leisure Line Lil' Heater (rental house)
Coal Size/Type: Rice and Buckwheat Anthracite

Re: Help with an auger feed problem!

PostBy: stovepipemike On: Mon Jun 30, 2008 7:51 pm

Matthaus ~ Thanks for the thinkers [opposite of klinkers,thinkers are Valuable]. I have recorded the website you provided for future use. I took your advise and went down to an old fashioned machine shop that caters to the local farming community.They have all sorts of neat stuff. I am started on the road to repair.What I am getting to really appreciate about this little boiler is that it is so straightforward in design that a person can actually make a few of the parts in a small home shop. It is interesting that the guy behind the counter[ their "auger guy" ] told me he had just purchased a DS Machine company coal boiler [hand fired] and is in the process of installation.He said 5 tanks of the oil that he usually needs would put him in the poorhouse this winter for certain. It looks like this coal thing is turning out to be an epidemic,I'm glad I caught it early because things are gonna get real tight real soon. I will keep this thread posted up as I make some advances. Regards, Mike
stovepipemike
 
Stove/Furnace Make: Keystoker
Stove/Furnace Model: KAA-2

Re: Help with an auger feed problem!

PostBy: stovepipemike On: Wed Jul 09, 2008 8:55 am

I want to give a follow up report on the repairs that have been completed.Upon disassembly ,I found that the auger went thru the back of the box and wore an egg shaped hole in the 1/4" material as well as cutting a deep groove in the auger shaft. I secured a new [to me] auger at an auction.It was stainless,oversized flights,different pitch,16 in. too long,.084" runout in 9.0 inches, and had a greater shaft size.Aside from that, just about perfect. Nothing that a little time in the shop could not cure,and for $5. how could I go wrong? I took the wiggle out in the press,cut the flights .100" undersize in the lathe,In addition, turned the shaft from .750" to .625" so I would not have to re-create a new shaker cam and buy a new Lovejoy connection. A .125" keyway was cut in the shaft using the Bridgeport so as to upgrade the set screw only securement system that the builder had used. Using the new auger I established a true center for the auger shaft. I welded in a bearing support and installed a bronze bearing for the stainless steel shaft. It moves like silk now. I also found that the 1/4" plate brackets that supported absolutely everything including the hopper were drilled wrong at the factory and causing all hang-on components to be not square and mis-aligned to the boiler, re -drilled and aligned same. Since I had it so apart ,I decided that I would upgrade the shaker system. It was changed from a loose fitting pin to a double set screw arrangement to secure the bell crank to the grate rod.There will be no lost motion now. The last item to be added was an additional support leg from the motor/hopper weldment to the floor. I took pictures of the job but as mentioned I do not know how to get them aligned with this post. Steel I can do,fuzzy frilly stuff,not so much [but trying]! Test firing and a measurement of the feed rate report coming. Thanks again for the help with this repair . Regards, Mike
stovepipemike
 
Stove/Furnace Make: Keystoker
Stove/Furnace Model: KAA-2

Re: Help with an auger feed problem!

PostBy: Freddy On: Wed Jul 09, 2008 9:41 am

Good going Mike! It sounds like a fun and rewarding steel job. Ya done good! :)
Freddy
 
Stoker Coal Boiler: Axeman Anderson 130 (pea)
Hot Air Coal Stoker Stove: Reading piece o' junk in the barn (rice)
Coal Size/Type: Pea size, Superior, deep mined

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