When people tell you about how difficult propane is to cut when compared to acetylene they are not really providing you with all the information.
FACT :
- Maximum neutral flame temperature of acetelyne in oxygen is about 5720[SUP]o[/SUP]F.
- Maximum neutral flame tempature of propane in oxygen is about 5112[SUP]o[/SUP]F.
The difference doesn't really matter as the real concern is for the thermal output
( BTUs ).
FACT :
- BTU's of Acetylene is approximately 1470 btu's per cubic foot.
- BTU's of Propane is approximately 2498 btu's per cubic foot.
So when they say propane gives off less heat it is not entirely correct
( plain wrong actually ). In the welding industry the vast majority of preheating is done with Oxygen / Propane . This is a fact . They don't do it just because it's cheaper but because the available heat from propane is much higher.
FACT : If you look at any torch manufacturers catalog, you will see Propane, Propylene and MAPP heating tips / nozzles of 250,000 btu/hrs to 1,000,000 btu/hrs. But if you look at the Acetylene heating tips / nozzles the maximum you see in the Harris catalog is a relatively small 240,000 btu/hrs, Smith Acetylene heating tip / nozzles are slightly less than 200,000 btu/hrs and Victor is about 300,000 btu/hrs. These are all far less than what they make for Oxygen / Propane use.