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Having some pretty big hammers has cause a dilemma :P How to heat such large stock efficacy enough to keep them running? I have been looking over the threads of both a ribbon burner and a oil burner type forge and could really use some input from those with experience with either. The target size material I would like to heat would be 3pc. 4" square to 2pc. 6" square around 16" long.

Thanks,

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DD, you mentioned oil burners in your steam hammer thread. We ran oil forges and a large furnace on oil in the blacksmith shop at the Burlington Northern Car Shops. They switched from coal sometime after WWII. Made myself an oil burner forge back in the early '80's when coal around here was hard to come by. Was just a modified fuel oil furnace burner. Took out the diffuser and drilled out the tip so that it shot a fine stream of oil. I could not get enough heat if the oil was a mist. Oil makes a soft heat a lot like coal and it was great for forge welding. With the price of fuel oil these days I am not sure how cheap it is to run. I did use drain oil for a while but the collecting of it got to be a PITA. The other draw back is the smoke and smell. You need a well drafting stack on your forge and your shop will smell more like a diesel garage than a blacksmith shop!

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Thanks for the input, it sounds like the oil burner may be more of an industrial setup. I have no problem with ventilation with two large doors on either end and a hugh exhaust fan at the peak. I would like to be able to store the oil outside and have the forge on wheels so it could be move around as well. It also seems there would be more cost at the front end with oil than gas, but I need something for rugged duty. When I fire up my Niles in the past it pretty much blew through anything I could get hot in the first heat! Some initial calculation that we have done is putting this build at 1,000,000 BTU...

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I initially made this forge to see if using a oil burner would even work about 5 years ago. It is simply a little house of hard fire bricks and the oil gun shooting into it at 90 to the stock. It is relatively easy to reshape the forge if I need to, sometimes I will make a tunnel with the burner at one end to get really long heats on pickets. Keep 30 or so cycling through at 24-30" heat.
Point is you should be able to get a used oil burner for cheap and make a forge of the size you need using better materials than mine.
Could probably mount multiple burners in one forge as long as they all started and stopped together. I dont think it would be good to have heat going out the non used burner if it shut down for any reason. Easy to wire the safety circuit to do that.
Also the inside needs to be large enough that the oil is burned before hitting the opposite wall. Adjustable somewhat with tip choice.

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  • 1 month later...

I will be interested to se what you come up with.
thermal mass of a forge is important if you are heating large objects. so hard brick liners to stop cool steel chilling the forge.
down side is that there is a long warm up time.
propane is becoming expensive here and heating oil is 30% cheaper...

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I wish I had 3 phase, just a 15 hp rotary converter. I looked at an big old induction heater at auction back before the small ones were popular, it was as big as a truck!

Calculation for forge capacity

5" x 5" x 30" = 2250 cu. in. divided by 1728 cu. in./ cu. ft. = 1.3 cu. ft. of steel
Raise 1.3 cu.ft. to 2250 deg. F. from 50 deg. F.
Specific of steel= .165 Btu per lb. per F deg.
1 cu ft of steel = 490 lbs., times 1.3 cu ft = 637 lbs
Raise 2150 deg. F deg net
.165 Btu/lb/F deg times 637 lbs times 2150 deg.F = 226,000 Btu's with no heat loss
Furnace size to be approx 2 ft x 3 ft. x 1.5 ft. = 27 sq. ft. of interior furnace area

A estimate of heat loss and refractory soak for walls are 4 1/2" or thicker. Gross heat input required to balance heat loss to fire-brick walls, the heat stored in the furnace wall as well as the heat which flows through the wall. An estimate of a 430,000 Btu's, with a cold start to temp of approximately 60 minutes.

226,000 Btu plus 430,000 Btu's = 657,000 Btu required as an estimate. Knowing that I may heat more or less, take more or less time to heat up, but knowing that I have the capacity to get a load up to forging temp in a reasonable time and that once the forge soaks out I would have some turn down capability to reduce heat input. Granted it is all an estimate but just trying to get as close as possible so that when the unit is built it will do the job that iI need to do.

Looking into the 750 burner http://hauckburner.thomasnet.com/viewitems/gas-burners/pbg-packaged-gas-burners? not cheap but as a complete unit the efficiency and the hugh turndown would be an advantage.

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Mr.Dillon,
That's a very interesting website. How is it, they have such high heat values with such tiny blowers? also are those burners for propane or nat. gas(I'm assuming nat gas).
Do you have the pleasure of knowing any glassholes(that'll pass the censors right?) in your area? They often work out of furnaces, that your average blacksmith would consider....ambitious. The 2 glass furnaces I've gotten to inspect and have a conversation with thier builder were about the size your considering( a hair wider, taller, not as long). One was heated with two fairly large ribbon burners on natural gas, the other was oil fired. I found the oil one befuddling as I had never seen an oil burner up close. It seems (oil) is a rather popular choice in large industry though so there must but some advantage of economy of scale.
Have you PM'd that kindly australian man? He has to have an answer. anybody who jury rigged a manipulator out of a forklift, has to have a passel of solutions for accommodating someone with the desire to work larger, right?
Take care, Matt

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I've got an oil burner that came out of a railroad shop (not the one I was in), it runs on compressed air, kind of a supercharged weed burner. A little bit messy on start-up and it sounds like there's an F-18 in your shop. It sure puts out heat. Just point it into a firebrick box. That shop called them "buckeyes" not sure where the name came from.
You might want to try something like that and I would really recommend a forge set-up rather than a furnace, for those times you need to take a second heat.

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Looks pretty basic Jim, except for the 5 legged stand :huh: I like your hinges as well. I once saw Capital Machine (they did machining on my big hammer) fire off one of those hooked up to a pull behind compressor, it threw a flame 20' and had a serious pucker factor!

Don't know any glassholes around here Matt, but I may have to look one up, would that make me a gaffologist :blink:

I'm really not for laying out that kind of $ for a burner, even the ribbon burners with all the safety whistles are expensive...

I keep switching back and forth, maybe Phil can shed some light on his set up.

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