Welding & Joining Technology: Oxyacetylene Welding

Oxy-Acetylene Welding 101 

Oxy-Acetylene Welding step by step process

Types of Welding Flames 

Information on welding flames

GAS WELDING - OXYACETYLENE 

Steps on operating a Oxyacetylene welder

 OxyAcetylene crossword Puzzle 

 Oxy_Acetylene_Unit_answer_key

Oxyacetylene Welding

Commonly referred to as gas welding, is a process which relies on combustion of oxygen and acetylene. When mixed together in correct proportions within a hand-held torch or blowpipe, a relatively hot flame is produced with a temperature of about 3,200 deg.

The process is used without the application of pressure. Oxyacetylene welding is limited to thin metal sections or to times when portability is important. Used on 11 gauge or thinner metal.

Equipment

Oxyacetylene equipment is portable and easy to use. 

The apparatus used in gas welding consists basically of an oxygen source and a fuel gas source (usually contained in cylinders), two pressure regulators and two flexible hoses (one for each cylinder), and a torch.

The regulator ensures that pressure of the gas from the tanks matches the required pressure in the hose.

Flame traps are fitted between the hoses and the cylinder regulators. The flame trap prevents flames generated by a 'flashback' from reaching the cylinders

The hoses are designed for use in welding and cutting metal. A double-hose or twinned design can be used, meaning that the oxygen and fuel hoses are joined together.

Between the regulator and hose, and ideally between hose and torch on both oxygen and fuel lines, a flashback arrestor and/or non-return valve or check valve should be installed to prevent flame or oxygen-fuel mixture being pushed back into either cylinder and damaging the equipment or causing a cylinder to explode. A check valve lets gas flow in one direction only.

The torch is the tool that the welder holds and manipulates to make the weld.

• A welding torch head is used to weld metals
• A cutting torch head is used to cut materials.
• A rose bud torch is used to heat metals for bending, straightening, etc. 
• A typical oxy-fuel torch, called an equal-pressure torch, merely mixes the two gases. In an injector torch, high-pressure oxygen comes out of a small nozzle inside the torch head which drags the fuel gas along with it, using the Venturi effect.

Oxy-fuel processes may use a variety of fuel gases, the most common being acetylene.

Flames

The welder can adjust the oxy-acetylene flame to be carbonizing (aka reducing), neutral, or oxidizing. Adjustment is made by adding more or less oxygen to the acetylene flame