Gas welding process of stainless steel plate and other metal parts

Gas welding involves the use of a gas torch to heat a metal workpiece such as stainless steel sheet and filler material to form a weld. The gas is usually a mixture of fuel gas and oxygen to create a clean, hot flame. Many different gases can be used as fuel for the gaseous fuel and no electricity is required to power the welding system, resulting in a flexible and portable fabrication method. All gas welding techniques require proper safety equipment for welding and storing welding gases.

Oxy-acetylene welding uses a mixture of acetylene gas and oxygen to supply the welding torch. Oxy-acetylene welding is the most commonly used gas welding technique. This gas mixture also provides the highest flame temperature of the available fuel gases, however acetylene is generally the most expensive of all fuel gases. Acetylene is an unstable gas that requires special handling and storage procedures.
Pressurized gasoline is used as a welding fuel where manufacturing cost is an issue, especially where acetylene tanks are not available. Gasoline torches may be more effective than acetylene for torch-cut heavy steel. Gasoline can be pumped manually from pressure cylinders, which is the practice of jewelry manufacturers in poor areas.
Methylacetylene-propadiene-petroleum (MAPP) is a gas mixture that is more inert than other gas mixtures and safer for use and storage by hobbyist and recreational welders. MAPP is also available for very high pressures, making it useful for high-volume cutting jobs.
Butane and propane are similar gases that can be used alone as fuel gas or mixed together. Butane and propane have lower flame temperatures than acetylene, but are cheaper and easier to transport. Propane torches are more commonly used for welding, bending and heating. Propane requires a different type of torch tip because it is a heavier gas.
Hydrogen can be used at higher pressures than other fuel gases, making it particularly suitable for underwater welding processes. Some hydrogen welding equipment performs electrolysis by splitting water into hydrogen and oxygen for use in the welding process. This type of electrolysis is often used in small torches, such as those used in jewelry manufacturing processes