So I have a vertical blown forge, it's designed like the one Ed Caffrey uses. Now I have no problem gettin it to a welding heat nor have I had any problems making damascus. I'm just wondering what pressures everyone else uses. I know almost every forge is different but before I open my ball valve the pressure is around 5psi. But once the forge is lit and running the line pressure is around 1psi or a little less. Does this sound normal? Am I using 5psi or 1psi? Any help is appreciated.
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What PSI does your welding forge run at?
- Thread starter NickBoyle
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1/4 PSI Residential Natural Gas in blown ribbon burner forge. 1/4 PSI is all I have out of the wall and easily can get 2400F degrees with great control over atmosphere. Designed right you can get away with very little PSI use.
Eric Fleming
www.flemingknives.com
Eric Fleming
www.flemingknives.com
Stacy E. Apelt - Bladesmith
ilmarinen - MODERATOR
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The pressure only matters on your individual forge. Running at the same temperature mine might run at more or less PSI. Each burner has its own operating pressure based on whether blown or venturi, orifice size, regulator size, delivery piping size, needle valve size, and hose/piping size.
It is exactly the same as volts, ohms, and amps. For a needed volume of electricity (amps) you either increase the pressure (voltage) or decrease the resistance ( ohms).
In a gas burner, pressure is one part of the delivered volume, the other is resistance to flow. What restricts flow is passage size. The things that restrict flow: Piping from gas supply, regulator size, valve sizes, Number of valves, hose/pipe sizes, length of all hoses from supply to burner, burner type, orifice size1CFM at 2PSI through a large valve is the same as 8 PSI through a smaller one. Just like in an electrical circuit, the main way to decrease the resistance by using a larger conductor wire/pipe.
As a general rule for knifemakers not connected to a gas well in an oil field ( we have some of those here) - 1/4 to 1/2PSI on a 1" residential natural gas pipe is about max; 1-6 PSI from a bulk propane tank is the normal range for a blown burner; 5-20 PSI from a bulk propane tank is the range for a venturi burner.
It is exactly the same as volts, ohms, and amps. For a needed volume of electricity (amps) you either increase the pressure (voltage) or decrease the resistance ( ohms).
In a gas burner, pressure is one part of the delivered volume, the other is resistance to flow. What restricts flow is passage size. The things that restrict flow: Piping from gas supply, regulator size, valve sizes, Number of valves, hose/pipe sizes, length of all hoses from supply to burner, burner type, orifice size1CFM at 2PSI through a large valve is the same as 8 PSI through a smaller one. Just like in an electrical circuit, the main way to decrease the resistance by using a larger conductor wire/pipe.
As a general rule for knifemakers not connected to a gas well in an oil field ( we have some of those here) - 1/4 to 1/2PSI on a 1" residential natural gas pipe is about max; 1-6 PSI from a bulk propane tank is the normal range for a blown burner; 5-20 PSI from a bulk propane tank is the range for a venturi burner.
I guess I kinda knew the answer, I know it has to do with each individual setup. It just seems like I'm burning thru a 100lb propane bottle pretty quick. I have a 40lb bottle on my Venturi forge and no matter how I run it, it seems to last forever! Maybe I should just be happy that the vertical, blown forge can max out my PID and I know I can forge weld in it. Now, if I only had a press instead of trying to swing a shortened 15lb sledge....!
Stacy E. Apelt - Bladesmith
ilmarinen - MODERATOR
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Tune it down to run at less air and less gas. I suspect that you are putting in more than it needs. Other things that may contribute are the refractory type and how much insulation it has, as well as the chamber size. Even in a good forge, running a welding forge for a day's damascus making uses up a lot of gas.