In this Instructable I show how to make a large burner. This burner can be used for heating a large pot of water or oil for big corn and seafood boils or as a super turkey fryer. Also home brewers will have use for larger burners like this. My use for it is actually for an outdoor wok station. I estimate its power output is 200,000 to 300,000 BTUs. There is some welding involved with this build but if you do not have a welder you could braze the pieces together. I built a 4 burner set up but you can reconfigure the pipe to make a smaller or larger burner. The only consideration is the propane regulator will need to be sized accordingly.
The Tools Used
- Drillpress or drill
- 1.3mm or #55 or 0.052" drill bit
- Common hand tools
- Four - 3" diameter schedule 40 steel pipe
- Four - 1/2" x 6" Black Steel Pipe Nipples
- Three - 1/2" Black Steel Pipe Elbows
- One - 1/2" Black Steel Pipe Tee
- Adjustable or 5 psi Propane Regulator
- Various misc fittings (ball valve, quick connect, reducing bushing)
- 20lbs Propane Tank
Important Warning: Do not attempt this Instructable if you do not have experience with propane and how it burns. If you are not comfortable around propane do not attempt this. When propane if used properly is a very safe fuel but bad things can still happen. This burner is very large and can damage you and property. You have been warned, I take no responsibility if something goes wrong.
Always wear safety equipment when lighting and working on the burner. At a minimum, safety glasses or face shield, cotton long sleeves or leather, do not wear synthetic materials as if they catch on fire they will melt to your body.
Step 1: Drill Orifice Holes
The middle of the 4 pipe nipples is where the orifice holes will be drilled. You can change the configuration but this is just the setup I went with. Drill one hole in the middle of each of the pipe nipples, I used a 1.3 mm drill bit, initially I used a 1/32" drill bit but it was tool small and I could not get the fuel air mixture correct for the burner to stay lit, using 3" schedule 40 as the burner tubes. Eventually I found 1.3 mm worked well for a 3" diameter burner tube. Go slow and use a drill press and cutting oil when drilling, these holes are small and it is easy to break the drill bit.
Step 2: Assemble the Burner Base
For the burner base, I went with an easy design by using 1/2" iron pipe fittings and made a square with 3 corners and tee fitting. The tee fitting is where the propane will feed into the burner. You could also use some 1/2" pipe and cut them at 45 degrees to make a square but I found with this I didn't need to do much cutting and fittings are cheap.
You will not be able to screw the whole assembly tight since it is a square, it is ok if the fit is loose. Make sure the holes that were drilled for the orifice are pointing upward.
Step 3: Welding the Base
Do not weld galvanized pipe, as the zinc fumes released are not good for you. I could not get regular black steel pipe so I stripped the galvanization off by soaking the pipe in a solution of vinegar over night before welding.
It's not possible to tighten the square with the fittings all in place so I welded all the joints to make them air tight. I used 3/32" 7018 welding rods. I think it would be possible to braze the joints too if you do not have access to a welder.
Step 4: Installing the Burner Tubes
The burner tubes are 3" diameter schedule 40 steel pipe. They are hefty and should not burn out.
Center the burner tubes over the orifice holes, you want the holes directly in the center of the tubes. Weld or braze the burner tubes in place. If you are brazing them in place it is probably is a good idea to grind out the 3" pipes with half moons so they fit on the 1/2" pipes. This will allow more surface area to be in contact for the brazing.
Step 5: Add Fittings to Connect to Propane Source
To connect the burner to a propane source, the 1/2" fitting will need to be coupled to fit your propane hose. I am using a quick connect rated for gas. In the picture the 1/2" tee is reduced to 1/4" by using a bushing then to the brass quick connect. Depending on what you get for a propane hose it may have different fittings, I like the quick connect as I have multiple propane appliances that I switch back and forth from.
Also make sure you install a ball valve between your propane source and the burner so you can adjust the size of the flame. The quick connect I purchased came with one already.
The high pressure regulator is adjustable up to 30 psi and with an optional pressure gauge.
Step 6: Testing
Before testing, I pressurized the burner and tested the joints for leaks with some soapy water. Fix any leaks as required.
Light the burner using a long bbq lighter or propane torch and do not stand over the burner. I started the test at 5 psi and turned the pressure to 10 psi and it seemed to burned very well. The flame was around 10" long. The size of the flame can be adjusted using the ball valve that turns the propane on and off.
Step 7: Intake and Choke
After experimenting with the burner, I notice that it works best when it is at medium to max power (valve fully open), but it was blowing out when the valve was turned down to get a smaller flame. I realized that the fuel air mixture was not right (too much air) when I wanted to have a small flame. So a simple solution was to restrict the intake, by using some metal tape,(you could also weld some sheet metal) and taping off part of the intake until it starts working well across the whole power range.
Step 8: Video of the Burner and Build Process
Here is a video of the building of the burner and the burner running.