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NARB LIVES!


Frosty

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One of this is a repeat from another thread if it bothers you. . . too bad. :P

The basic T hasn't changed, the thread protector is just welded to a square steel tubing plenum. Open along one side, ends capped. The open side is molded into the cast refractory burner block with ports made with crayon cores in the mold.

I'm still playing with tuning the things but I don't know if the over much orange dragon's breath is caused by a too rich flame or it's the refractory curing or a component there of.

Mine is based on John Emerling's Ribbon burner first published in the Hammer's Blow I believe year ago. The main mods I made is eliminating the baffle to disperse the fuel air mix in the plenum. The thought is logical but as installed is the #1 reason the things need such a high static pressure blower to work. The test ribbons I played with with the T aimed in line with the ports benefited from a baffle but not one so hard against the main inlet. I welded a bent V half way across the plenum so the input wasn't blowing straight down any outlets. It worked just fine in the test blocks.

Then I got the brainstorm that the inducer didn't need to enter the plenum at any particular angle so I welded it at a 90* angle and left the baffle out completely. It works SOOOO much better and the T inducers lay flat on the forge shell, completely out of the way and out of the exhaust plume.

Thanks to MonkeyForge for being able to Save As the pics posted on the club FB page I have a couple pics of it running at the club meeting 09/24.

Oh and this IS on topic, it's a NEW forge. :ph34r:

It'll be a while before I even attempt a how to post or thread or whatever. consider this a sneak preview of something that has me pretty jazzed but needs work.

Dang I must be slipping this is the 3rd time I've tried getting the post W/pics in the right thread. <sigh> Now I have to remember what I wrote.

The first pic shows the burner flames, the burner on the right got debris in some of the outlets when I was plastering the Kast-O-Lite refractory and needs cleaning. The burner had even clear flames when I tested it so this is temporary.

NARBinforge02.jpg..jpg

 

This pic shows how the T inducers lay flat on the shell with the air intakes at the back. There were gusty breezes coming in the shop door and it didn't huff once. The fuel lines are the promised rush kludge job I mentioned. The welds on the shell also show how rushed I was to get this thing working in time for the 09/24 club meeting.

The excessive dragon's breath as shown in the pics is a bit of a mystery, the burners appear to be burning near neutral and looked so in the brick pile when I tested them. I THINK it must be products from the refractory curing. The exhaust plume is largely responsible for the shell warpage visible in the pics. the strip over the opening looks like bacon now, I need to come up with shielding or get used to a crinkly forge.

The piece of rigidized Kaowool leaning on the side is covering one of two through ports. Long stock passing through the forge lay between the burner flame and the back wall, Even HOT sweet zone.

NARBin forge01.jpg

 

That's in so far, I am not displeased. B)

Frosty The Lucky.

 

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17 hours ago, Frosty said:

 

The excessive dragon's breath as shown in the pics is a bit of a mystery, the burners appear to be burning near neutral and looked so in the brick pile when I tested them. I THINK it must be products from the refractory curing.

 

Might also be left over crayon burning out in the openings of your burner.  Amazing how long that can persist.  I cured my multiport burner up to 1450 deg. F in my heat treat oven.

Looks good to me, though I anticipate that like me you will be working out a more sophisticated door design eventually.  Nice job!

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I have been eagerly awaiting this post as I have hopes of making a NARB this winter.   I have some questions, I know this is a sneak preview so please use these questions as primer for your How-To post to come out.

 I was surprised to see a twin burner setup.  Are these 1/2" T Burners? I assume you are estimating the same  forge size capacity per burner as a round  burner?

Is a square forge design more appropriate for a ribbon burner?

As I recall you used 19 outlets in the manifold, what are the dimensions of the steel tubing manifold?

Thread protectors, This is not a question, I just have not come up with any yet.

Is it quiet?  This is more related to the dragons breath you are getting.

And I owe you a thank you for taking this on, Thank You.

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The flame pattern and color is inconsistent with a reducing flame. Also if that much 'secondary' flame was do to very incomplete combustion, the equipment couldn't attain such high temperatures.  It is more likely that you simply need to turn down the gas input or back pressure. I get the same thing from when running one of my burners at wildly high gas pressures inside a forge. Your burner is a kind that is designed to have a very soft exhaust, while my burners have very forceful exhausts, which only become more so at this point; also inconsistent with a rich flame The same burner running at the same pressure in open air burns hot and neutral. I never pursued the cause of this effect, since the cure is so simple. However if you solve the mystery I will be glad to hear about it.  If you wish to investigate further, some clean metal placed in the exhaust stream may become coated in carbon, or in something else, providing a clue.

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That should have read:

The flame pattern and color is inconsistent with a reducing flame. Also if that much 'secondary' flame was do to very incomplete combustion, the equipment couldn't attain such high temperatures.  It is more likely that you simply need to turn down the gas input. I get the same thing when running one of my burners at wildly high gas pressures inside a forge. Your burner is a kind that is designed to have a very soft exhaust, while my burners have very forceful exhausts, which only become more so at this point; also inconsistent with a rich flame caused by back pressure. The same burner running at the same pressure in open air burns hot and neutral. I never pursued the cause of this effect, since the cure is so simple. However if you solve the mystery I will be glad to hear about it.  If you wish to investigate further, some clean metal placed in the exhaust stream may become coated in carbon, or in something else, providing a clue.

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Uh let's see, in order.

Nope The crayons were cleaned out completely. One day setting and cold curing at around 110f. Magnetic engine heater on the plenum and wrapped in Kaowool. Another day with the engine heater after I'd stripped the mold. Then I lit a double handful of charcoal briquettes with the outlet block on the fire covered and let it cook over night. Last step was going through each outlet and cleaning the ash and debris followed by the air hose from both directions.

Not crayon residue.

Those are standard 3/4" T inducers, each one connected to an individual plenum and ribbon block.  I'd have to go through the whole test process again to determine how many outlets worked properly with a 1/2" inducer. I'll let someone else do that. I'll lay out my test mockups in the write up.

I haven't had one of these things long enough to have an opinion of what furnace shape is most appropriate. They're quieter than a round nozzle T burner, not quiet but not nearly as loud as the old fashioned T burner. You can stand right next to it and speak in normal tones.

Mike: So we see the same thing in the flame, it didn't look rich to me either but the huge orange exhaust plume had me wondering. No sooting on cold steel placed anywhere in the chamber, better still no scaling even at the edges of the flame.

Observations don't bear out a psig cause. It's running at under 8 psig in the pics and produces a large orange exhaust plume turned down till the gauge was pegged hard at 0. Larger but not a lot worse when cranked to my reg's max of 20psig. More psi produced more orange flame of course but as long as it was burning there was orange dragon's breath.

Nobody tried welding in it so there's no borax yellow/orange in the flame. Neither ribbon produced nearly the amount of orange flame when I tested them in the brick pile chamber. However the blocks are KastO-L-ite 30 as is the flame face in the forge. I cured the rigidizer in the old shop forge and didn't observe odd colors.

This is leaving me wondering if. . . Okay thinking it's a byproduct of curing the Kast-O-Lite30. The only thing that trips a memory file for me as burning orange is calcium though what I've seen was a beautifully VIVID orange. Oxy lance course, DOT personnel are on FEMAs list of emergency responders in disasters so we got to play with some really cool stuff. Concrete burns with a VIVID orange smoke, don't get it on you!!!:o Super heated quick lime is an unpleasant skin defoliant.

Anyway, Kast-O-Lite uses calcium (something I don't recall) as the cement / binder and that's where my thinker is right now, at least till something more likely comes along.

Frosty The Lucky.

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The forge ran about 4 hours at the meeting and was running hot enough soft fire brick wouldn't have survived. I don't believe there were any ill effects from the dragon's breath I'm just really curious.

Oh, if about 20 Alaskans drop dead mysteriously at the same time call the CDC please.

Frosty The Lucky.

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I have produced similar effects in yellow flame; have not had orange in (equipment) exhaust fumes. To completely cure Kast-O-lite 30 you have to take the product up to yellow heat; I always settled for merely calcifying the inner face to about halfway through the wall; anything more is pretty hard on surrounding materials:unsure: Calcifying is an outdated term for completely curing a refractory material. My interest in doing so at the time was to produce as close to a waterproof product as possible in a furnace that lived in a garage in rainy Seattle. 

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