gas welding Oxy Acetylene ( OXY ACETYLENE WELDING : OAW ) is a melt welding process. by using heat from The fuel is a mixture of acetylene gas and pure oxygen gas. Combustion produces a high amount of heat. make the melting piece homogeneous The welding wire can be filled or not, depending on the thickness of the work and the type of joint.
Fuel gas type and maximum heating value
There are many types of fuel gas, when mixed with oxygen it produces higher heat than normal combustion. For the gas welding industry mixed gas between oxygen gas and acetylene gas It is widely used. because it provides higher heating value than other types of fuel
Flame in oxyacetylene gas welding
Gas welding is a metal welding process that has been used for a long time. Which at present is still widely popular. The heat of combustion between oxygen gas and acetylene gas Provides a high-heat flame of about 6,300 degrees Fahrenheit or 3,480.
degrees Celsius is sufficient to allow the metals to be fused into a homogeneous mass. When cooled, two metals bond together to be equal or greater than the original metal. The flame used for welding has the following components:
treasure of flame
Flames used in welding with oxyacetylene gas must have the following properties:
– The temperature is high enough to melt the workpiece.
– There is enough heat when needed
– There must be no impurities from the flame. or bring one of the objects come together with the molten metal
– The flame must not add carbon to the metal, which will cause The properties of metals to change.
– Flames must not be hazardous to chemical workers.
flame type
to be suitable for each type of metal welding flame therefore divided into 3 types as follows:
Reduced flame or very carbon flame (Carburizing Flame)
It is a flame resulting from the combustion of oxygen and acetylene gas. The amount of acetylene gas is greater than that of oxygen. The outer flame is a long, orange colored flame surrounding the inner flame. which is half the length of the outer flame The inner flame will look like a feather. At a distance of about 3 mm from the cone, it has a temperature of 5,700 degrees Fahrenheit (2,800 degrees C). The combustion has a certain amount of acetylene gas remaining, so it is suitable for welding applications that require carbonization on the metal surface. or welding non-ferrous metals which require a very high melting temperature such as aluminum, magnesium and used in brazing.
Neutral Flame
It is a flame derived from the mixing of oxygen gas with acetylene in a ratio of 1:1. It consists of two layers of flame, the inner layer is a funnel-tip. At a distance of about 3 mm from the tip of the cone, it will have a temperature of approximately 6000 degrees Fahrenheit, or 3,150 degrees Celsius (3,150 0C). When this flame is burned, ferrous metal melts into a water-like metal well, and when cooled, welds are formed. clean, strong This type of flame is therefore suitable for welding and cutting metal. especially steel due to complete combustion therefore does not add carbon to the weld
Increased or very oxygenated flame (Oxidizing Flame)
It is a flame that is derived from the mixture of oxygen gas and acetylene gas by adjusting the oxygen more than acetylene. The flame has 2 layers. The inner flame is a short cone-shaped cone. This flame has a higher temperature than the other 2 types of flames mentioned above. It has a temperature of about 6,300 degrees Fahrenheit or 3,480 degrees Celsius. When welding, sparks or sparks will come out of the molten pool. causing air bubbles to be unsuitable for welding steel Because of incomplete combustion, there will be residual oxygen and will be added to the steel. make the weld brittle but is commonly used for cutting thin sheet metal
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