What chemical processes are involved when using a blow-torch?

Question

...on steel?

AND what does the blue colour of the flame signify? What chemical is being burned?

Answer 1

It doesn't matter what your using the torch on, the chemical process occurring is known as combustion.
The hydrocarbon fuel used on the torch is chemically reacted with Oxygen (either from the air, or sometimes a separate Oxygen gas tank) in an exothermic, combustion reaction.

Ideally, the only two products of a combustion reaction are water and Carbon Dioxide, but often due to impurities in the fuel and the fuel not completely being oxidized, other, more hazardous, gasses form such as Carbon Monoxide.

EDIT:
The blue (non-luminous) flame indicates that the fuel in undergoing complete or near complete combustion. A non-luminous flame is much hotter than a luminous flame (the usual yellow flame you might see on a candle or match) which is undergoing much less complete combustion.

Answer 2

They use the blow torches to do what's widespread as "scuffing" the tires. some Drivers at particular tracks do unlike commencing off with what they call "decal tires" that are tires with the stickers nonetheless on and are many times very slick. "Scuffing" the tires supplies further traction with the help of offering a coarse floor on the tire and likewise heating the tire up so it sticks to the song extra effective. additionally, Crews try this to tires taken off the automobile to be certain basically how plenty rubber is left on the tire to be certain the right volume of tire positioned on and basically how close the tire is to failure. In F1 they even have tire warmers that bypass on the tire till the automobile is able to bypass, that way the tires are severe high quality and sticky giving the automobile a lot of traction on starts and restarts.

Answer 3

you are a burning gas to make heat the blue flame is the oxygen burning the bluer the flame the more oxygen is being burned

Answer 4

I thing it is gas