harrismetalsmith

Ribbon Burner Blower

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The blower you need is dictated by the ribbon burner. Ribbon burners that require blowers (yes, there are ribbon burners that don't) need to have a plenum pressure maintained. Most blowers will not provide pressure against restriction.... When there is a restriction (as provided by the plenum and burner holes), most fans will just spin and not push air (thus not providing the required pressure for a ribbon burner to operate properly). The pressure measurement is generally specified in Water Column inches.

I bought the smallest PINE RIDGE ribbon burner and tried to use a 112 CFM blower I bought from Blacksmith Depot. The burner worked, but would not get the forge as hot as I wanted it. I think Larry Langdon built a ribbon burner forge (not sure what burner he uses) and has had success with the 168 CFM fan from Blacksmith Depot. Whether or not it works for you will be determined by the burner design.

Is your burner one you made, or one you bought commercially? If it is a commercial burner, your purchase source should be able to tell you what the pressure requirement is (it will be a range of WC inches, the more pressure, the higher the performance of the burner). If you made the burner yourself, you just have to test blowers till you find one that performs as you need it to. CFM rating of a blower is not the issue here. You could have a 500 CFM blower that would not work, pressure is the issue. In general, fans with paddles produce pressure, squirrel cages do not. Not all paddle fans work efficiently.

A simple water column pressure gauge can be made to measure the pressure while the fan is running. All you need is a port into the pressurized area (pipe or plenum) and a clear plastic hose. I added a port by drilling a hole into an elbow and tapping it with a 1/8th inch NPT tap, then screwed in a brass fitting I could push a clear hose on.

A fan I found that works for me is a fan designed to be used to blow up a moon bounce. I would not recommend this fan because it's too noisy. I regulate the speed of the fan (full speed is too much) with a commercial high amperage reostat.

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Matt, I have two naturally aspirated forges and built two different ribbon burners for a third forge. The ribbon burner is the only one that I fire up these days. One of the things that I learned was that the ball valve on the exhaust side wouldn't let me fine tune the burner. Seemed that it was 'all or nothing'. Then I learned somewhere that a butterfly valve is linear in controlling the volume/velocity. Made a big improvement....The radial blower I use is oversized because it was free so I can't help there. But make sure you don't undersize your tubing to the burner. 2 or 2 1/2"
With the volume of air, I ended up taking off the back door to allow the forge to breath...Like any forge, you cant have too much back pressure or it just won't work.....Let us know how it comes out...remember, everyone likes pictures....Keith

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Ok guys, thanks for the input. I will post pics of my current setup next week. I didn't realize the paddle blade fans provide more pressure than the squirrel cage ones. Right now I am using a old Champion electric forge blower. I just don't think I'm getting enough from it right now. Territorial, I will take a look at the size of my supply pipe, I think its 2". Built this a while back, but I haven't used it much because its not working right.

By the way, do you guys have a favorite angle or direction to angle your burner into the chamber? With my old style forced air forges I sent it in from the top angled for a vortex. With the ribbon burner I sent it straight in from the top. The inside chamber is aprox. 11" diameter.
I'm thinking of going back to an angle with the ribbon style to create a more natural vortex. Right now the ribbon hits the bottom of the forge and rolls out evenly on both sides. Like I said earlier I will post pics next week.

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Matt

Personally, I wouldn't expect moving your burner would make any significant difference. It appears to me the heat coming off my ribbon burner acts more like a radiant heat source than blast heat (like from a pipe burner). I doubt there would be much swirling action. Just my opinion....

Actually, I have two fans that will provide enough air. The one on the left is a commercial fan used by pool maintenance folks (for a vacuum source) and the other is the one that is designed to fill (and keep filled) something like a moon bounce. Both of these fans are louder than I want, but they do work. Some folks use an air gate to control air volume. As I mentioned before, I use a large amp reostat. I doubt these fans are good choices if the forge is used a lot. If I end up using a ribbon forge a LOT, I will buy an appropriate blower (Blacksmith Depot has (what looks like) a high performance paddle blower for $250. It's possible their $150 blower would work for you (it apparently has for others with some ribbon burners). Right now, playing with a ribbon burner forge is just an experiment for me. Up to this point in time, I haven't had a lot of use for large forge. My primary goal was to build a forge that was quieter than the ones I normally use. My experience has been that if I want a high performance forge, it comes with noise... which is generated either by the burner or the fan.

I picked these fans up cheap (auction and flea market). I'm still looking for that perfect appropriate (quiet) fan that doesn't cost an arm and a leg. I'm not convinced they really exist (new prices anyway). I've even considered putting the fan outside (along with my air compressor and a hydraulic unit) and piping in the air to the forge.

To check to see if a blower may have the pressure to make a ribbon burner work, run the blower full out and put your hand over the output port. If the fan aggressively trys to push air, it may work. If not, the fan is just spinning and will not produce the pressure needed for a ribbon burner.

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Thanks Dave. I think a good initial plan of action is to replace the blower and go from there. I may steel the one off the moon bounce my father in law bought for the kids. :rolleyes:
I'm not sure about the location of the burner. My chamber is totaly round, so creating a natural vortex, instead of fighting it seems more natural and logical.

Also wondering about gas pressure. I've heard that ribbon burners use less gas, but do they need a higher pressure than is generated by my 100 lb. tank. Is the concept less volume at a higher pressure?

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Thanks Dave. I think a good initial plan of action is to replace the blower and go from there. I may steel the one off the moon bounce my father in law bought for the kids. :rolleyes:
I'm not sure about the location of the burner. My chamber is totaly round, so creating a natural vortex, instead of fighting it seems more natural and logical.

Also wondering about gas pressure. I've heard that ribbon burners use less gas, but do they need a higher pressure than is generated by my 100 lb. tank. Is the concept less volume at a higher pressure?


Your forge will not need more pressure than your 100# tank will give you. You do need to be able to easily control the stream of propane though. I use a high pressure regulator cranked all the way up (at least 30#. I use a 0-60 lb regulator), and control the propane with a needle valve. You need to have a very good (not cheap) needle valve. I use Alcon needle valves (a little over $20 each). I put the needle valve at the point of propane entry. The blower and propane stream should be turned down when the forge is first fired up. Let it warm up a bit, then increase the air and propane a little at a time the same way you would increase the flame on an OXY/ACET torch. Sounds and sight (mostly sound) tell you when you have an optimum burning ribbon burner (at least that's how I do it).

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My ribbon burner forge is pretty big, but I can freeze up a 100# tank in a couple hours, not that it wont work but I got to change tanks every couple hours to let the tank thaw.... Im sure I could manifold two tanks together and solve that. The forge I built is not my every day forge, it is for big stuff, large projects and I am quite happy with it.. I original built it with a small ball valve in the pressure side to vent extra air off, I have since replaced it with a 2.5" gate valve to better control the air (as a plug my Dad has lots of surplus 2.5" gate valves if someone needs one for a forge project, I think he would sell one for about half what it would cost at a hardware store, he can also include the nipple to weld into the system) I think I am right at the edge of blower pressure for my forge and think I might try a larger blower at some point..

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Here's an old photo with the ball valve. When I adjusted the inlet choke on the blower, it started to cavitate/free wheel. The ball valve was better but beyond 1/2 turn, it just dropped out. I learned about the linear characteristic of butterfly valves used in the exhaust port on my kinyon hammer......check out McMaster Carr. 2 1/2" valves are a little expensive so I "cheated" and made mine on the milling machin with a pvc coupler, 3/8" bolt and a steel disc. One could be made with a drill press and some patience...Keith

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Here is the blower I have on the forge currently. Also a pic of the inside of the forge. The forge body is made from a piece of large pipe from the scrap yard 12" I.d. and 13" o.d. inside of the forge is aprox 9 1/2" I.d. as seen in the photo.
I notice most of your forges have the blower at the bottom with 2, 90 degree elbows. Doesn't this create even more resitance for the blower to work against?

I am wondering if I should put a gate valve on my current setup? I have never controlled the air flow. Maybe instead of not enough air, I have too much? Just wondering out loud, please feel free to give an opinion based upon your experience.

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Here is the blower I have on the forge currently. Also a pic of the inside of the forge. The forge body is made from a piece of large pipe from the scrap yard 12" I.d. and 13" o.d. inside of the forge is aprox 9 1/2" I.d. as seen in the photo.
I notice most of your forges have the blower at the bottom with 2, 90 degree elbows. Doesn't this create even more resitance for the blower to work against?

I am wondering if I should put a gate valve on my current setup? I have never controlled the air flow. Maybe instead of not enough air, I have too much? Just wondering out loud, please feel free to give an opinion based upon your experience.

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IMHO, I think you have to have a way to control the air, also the propane. My experience was that the air pressure and propane volume need to be balanced (therefore adjustable) to get a good burn environment. I'm not sure you could get the forge started if you had too much air.

I don't think the position of the blower (or a couple elbows), if it has the proper capability, makes any difference. It just has to maintain the pressure.

Maybe the next time I go up to visit my daughter (Delaware), if you are working, I can stop by and look at your setup with you.

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For a propane burner; turbulence is a good thing as it helps to mix the propane and air properly and so many burner set ups make use of "un-needed" bends to encourage it.

Also to be considered is the possible paths of exhaust gasses as re-running exhaust back through the burner is an EXCELLENT way of producing massive amounts of Carbon Monoxide. As hot gasses generally rise, lower can help separate the combustion air from the exhaust air.

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I built a large ribbon burner forge, Hammers Blow design. But I dont seem to be getting enough presure from the blower.
If you have a ribbon burner forge, what do you use for a blower? CFM? Model? Suplier?



Hi,
I wrote the article for the HB a long time ago. The blower you need can be purchased from Centaur, or BS Depot. Get the highest cfm you can get from them. Run the blower at full speed/pressure and regulate the air with a gate valve btw the blower and the gas inlet. Whatever you do, do not try to regulate the air with a rheostat on the motor. That will ultimately reduce the air pressure. You want to keep the pressure constant and reduce/increase the volume.

The ribbon burners can be used with either nat gas or propane. Nat gas needs a larger orifice...say 3/16+. The key is to simply get the fuel into the line. The air pressure will take care of the rest. Regulate the forge flame by inc/dec the gas/air to a neutral flame within the forge, much like adjusting a torch.

Also, keep in mind that residential natural gas pressure is in inches of water column, not lbs. My commercial rating is about 2 lbs. of pressure. That's more than I can use. With propane, you may want to start w/a .045 welding tip, and maybe increase the size from there if necessary. The advantage of higher pressure in propane is that it gives you somewhat more fuel control.

One thing I've noticed about forging with propane is that it burns hotter and uses less air, resulting in less scaling on the steel. Nat gas requires more air and a longer time/space to mix the fuel prior to entering the burner. Rule of thumb is that nat gas should enter the pipe 9 times the diameter of the pipe, ie, a 2" pipe x 9 equals 18" ahead of the ribbon burner. Propane mixes readily and the inlet can be much closer.

Good luck,

John

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My quest for the perfect ribbon burner forge led me to buy the largest LP series burner from Pine Ridge Ribbon burners. Needless to say I am extremely impressed by the way it was made and the way it burns. Well worth the money.
As far as the hammers blow design goes, I think the refractory I was originally using was 2500 degree, not 3000. Big mistake and explains why the first 2 I made cracked out. I am casting a new one with the 3000 refractory I picked up, and I plan on having more steel fingers come down into the mold for a better meld between the steel and refractory.

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Harris,

Could you show pictures of your final design? I'm in the process of learning about the design and operation of  blown ribbon burner forge. 

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