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Hey all, I have gotten a lot of questions locally about my self built forge burner, so I figured I would post some pictures here as well. I designed this burner based on a hybrid of a blower burner and a Venturi burner. My original intent was to use it as a Venturi burner until I could put together a blower assembly for it, but it works so well I have never bothered to do the blower. Standard disclaimer: I can not be responsible for your actions! Please build responsibly! Propane is flammable and in just the wrong mix it is explosive! DO NOT attempt to build a propane burner without first understanding the function of each part and how they work together. This information is just that, information, please do your own homework before attempting to use any information from any source. *Don't forget to check on any local building codes related to propane appliances or tank location etc. *DO NOT USE GALVANIZED PIPE, use only brass and black iron piping as specified, parts of the burner will get hot and galvanized pipe releases NASTY fumes when heated. * This burner design easily reaches temps in excess of 2,000 degrees F, producing damaging IR spectrum light! I strongly recommend the use of IR shade 3 glasses whenever looking into a hot forge (my personal thanks to Dave Stephens for this piece of advice!) OK on to the burner, I have no way to measure the BTUs, but according to the BTU calculator on Ron Reil's burner page (ronreil.abana.org/design2.shtml) when tuned to a neutral burn, it should produce 46,000 BTU per hour at 5 psi and 93,000 BTU per hour at 20 psi. Those figures are consistent with my gas consumption rates, so I am fairly confident in calling them accurate. I will say it is easily capable of welding heat and turning 1/4 in mild steel rod stock into a sparkler...not that I have ever done such a thing: Parts list 1/4 in ID gas rated ball valve 2 in long 1/4 inch ID threaded brass pipe 4 in long 1/8 inch ID threaded brass pipe 1/8 in brass Female threaded coupling 1/8 in male brass plug You could replace the coupling and plug with a 1/8 in threaded brass cap, I wasn't able to find a cap. Brass contact nipple for a MIG welder (0.035 in; 0.9 mm) 1 1/4 in Black iron pipe T junction 1 1/4 in x 1 in Black iron reducer bushing 1 1/4 in x 3/4 in Black iron reducer bushing 3/4 in x 1/4 in Black iron reducer bushing You can replace the last 2 bushings with 1 1/4 in x 1/4 in Black iron reducer bushing if you can find one. 18 in long x 1 in Black iron pipe 3 in square sheet steel 3/4 in #6 machine screw largish ball point pen spring (needs to fit over the machine screw shaft) Pipe thread sealant RATED FOR Propane!!! High Heat spray paint (I used Rustoleum brand, rated for 1,200 degrees F) Tools: pipe wrench tap wrench #6 NC 32 tap and appropriate drill bit 1/4 in NF 28 tap and appropriate drill bit 1/8 NFP tap crescent wrench or 2 First off, assemble the Black iron pipe as shown using a small amount of thread sealant: 1 in pipe off one side, 1/4 reducer bushing on the opposite side with the perpendicular opening left open. Once assembled, clean off any excess thread sealant so the paint will stick, then paint the entire assembly with the High Temp paint. Set that aside and start on the Brass fittings use plenty of thread sealant, I don't bother to paint the brass. On the inflow side of the ball valve, attach whatever propane fitting is needed to connect to your propane source. For mine this was a 3/8 in flare fitting. Take the 2 in long x 1/4 in brass pipe and tap one end with the 1/8 NFP tap, then thread the opposite side into the outflow end of the ball valve. Take the 1/8 in brass male plug and drill a 3/16 in hole through the center of the face and tap it with the 1/4 in NF 28 tap. Then thread the MIG nipple into it, the plug into the coupler and the coupler to the 4 in long x 1/8 in brass pipe: Next slide the 1/8 in brass pipe and MIG nipple assembly down the 1 in black iron pipe such that the end of the 1/8 in brass pipe protrudes from the 1/4 in reducer bushing and the MIG nipple points down the pipe. Thread the 1/8 in brass pipe into the end of the 1/4 in brass pipe that was tapped earlier: Then slide the brass assembly into the black iron pipe threading the 1/4 brass pipe into the 1/4 in reducer bushing: The 1/8 in brass pipe and MIG nipple assembly should point down the center bore of the 1 in pipe extending through the T and into the 1 in black iron pipe. The careful observer of that last picture will note a small hole in the rim of the open end of the Black iron T. That is drilled and tapped with a #6 NC 32 tap. Drill a 5/32 hole in the corner of a small piece of sheet steel, place the spring over the shaft of the #6 machine screw then put the screw through the corner of sheet steel and thread into the drilled and tapped hole on the rim of the Black iron pipe. This provides a damper for air control. Note, the spring needs to be stiff enough to keep the sheet steel in whatever position you slide it (open; closed; partial...) Here is a pic of me and my assembled burner during it's first test burn 4 years ago (NOTE: This burner will not sustain a flame outside the forge unless the damper is closed, robust air flow will literally blow the flame out. I have my hand covering the opening on the T since I had not yet fitted the damper.) I will cover the flare nozzle in a reply post since it is integrated into the forge design. Hope this helps someone, any questions shout em out. James Edit to add orfice size on MIG contact nipple and to correct thread count on the 1/4 NF 28 tap. Finally added pic of damper assembled.