Saturday Science Sessions – Playing with Fire!
A propane torch is a very flexible repair tool for low-heat applications. This type of torch provides low heat because the flames at the tip spreads out, which diffuses the heat. There are also other factors such as incomplete combustion. An oxygen-fuel torch contains two separate tanks; in this case a tank for the propane and a tank for oxygen, and is usually lit via a flint striker. Essentially you place the striker over the tip nozzle, and strike to ignite the gas. There is usually a loud ‘popping’ sound if there is an incorrect ratio between the fuel and oxygen!
Increasing the amount of fuel results in a larger, orange flame (more soot and therefore cooler in temperature), whereas increasing the amount of oxygen results in a smaller, blue flame (less soot and therefore less heat radiating away, resulting in a hotter flame). The amount of fuel or oxygen can be regulated directly on the tip nozzle through valves. Applications include soldering copper pipes or low temperature welding applications. Definitely fun with fire!