A carburizing flame is one that has more acetylene than oxygen in the mixture. There are three types of flames natural flame, carburizing flame and oxidizing flame. 2 Carburizing flame or Reducing flame: Because of short supply of oxygen from O2 cylinder the flame has traveled for longer distance for complete combustion. If a metal that absorbs carbon is welded using this flame then the properties of the metal will be changed. A carburizing flame burns in three shades of blue—a light blue conical-shaped flame at the tip of the nozzle is surrounded by a darker blue flame, and both of these are enclosed by a layer of even darker blue. When used in silver solder and soft solder operations, only the intermediate and outer flame cones are used. This flame has an excess of carbon or acetylene, far above the amount needed to react completely with the oxygen issuing from the blowpipe. The flame plays lead role to create weld joint and the weld properties are highly depended on it. It has a yellow feather on the end of the primary cone. This flame does not oxidize metal, as there is an insufficient stoichiometric level of oxygen in this flame to consume the acetylene gas. This denotes excess acetylene. Sometimes this flame is called carbonizing. 2. Figure 4-17 shows how the three different flames look when using MAPP gas as the fuel. Depending on the amount of time and temperature, the affected area can vary in carbon content. This flame is more smoky and quiet. hence the length of the inner cone will be 2N to 3N. Carburizing; The flame temperature is melting the base metal; it flows and fill the gap between the work piece. In this flame more fuel gas is used as compared to oxygen. There are three types of gas flames commonly used for all oxygas processes. To ensure proper flame adjustment, you should know the characteristics of each of these three types of flame. Natural flame has synchronized mixture of fuel and oxygen, carburizing flame has more fuel and oxidizing flame has … They are carburizing, neutral, and oxidizing. A carburizing flame is advantageous for welding high carbon steel and hard facing such nonferrous alloys as nickel and Monel. It base metal thickness will be low. A pure fuel-gas flame is long and bushy and has a yellowish color. 2) Carburizing Flame:-This flame is called carburizing because when this flame is used in welding then metal carbide is formed. The carbon in the acetylene is not completely burned, and the flame will add carbon to the metal being welded. Carburizing Flame: In carburizing flame, round the inner blue luminous cone on the tip on the jet is a feathery white colour. The coalescence liquid is enough to fill the gap. Slightly carburizing or "reducing" flames are used to weld or braze easily oxidized alloys such as aluminum. They impart a … A carburizing flame looks much the same with MAPP gas or acetylene. Carburizing Flame: A flame which produces iron carbide (not recommended for carbon-absorbing materials) Oxidizing Flame: It has more temperature than that of a neutral flame (Recommended for Copper or Zinc) Neutral Flame. Also called natural flame, a neutral flame is the most common and widely used flame type out of all. Carburizing flames are obtained with MAPP gas when oxyfuel ratios are around 2.2:1 or lower. This process is called carburizing. Carburising, carburizing (chiefly American English), or carburisation is a heat treatment process in which iron or steel absorbs carbon while the metal is heated in the presence of a carbon-bearing material, such as charcoal or carbon monoxide.The intent is to make the metal harder. If want to more thickness of base metal and additional metal (filler metal) required.