Forced air burners commonly have larger orifices than Atmospheric burners. A Forced air burner with a 1/16" (0.0625) orifice will use a little over 3lbs. of propane an hour at 2 PSI. An Atmospheric burner with a .040 orifice needs to run at a pressure of 12 PSI to flow that much propane. From most of the designs I've seen, forced air burner orifices are even larger than a 1/16", I've seen some as large as 1/8" (0.125).
PSI means NOTHING, you need to know what the flow rate of the gas is to make any kind of reasonable determination. Forced air systems have their place, when you want very precise control of the fuel/air mixture, but for any Blacksmithing/Bladesmithing, Atmospheric burners with a good choke are all anyone really needs. You never need to worry about the danger of explosions when the blower quits either!
|