Neutral burning with an increase in the supply of oxygen to the soldering tube, especially when argoning occurs, the white cone of the flame becomes clearly defined. At this stage, approximately equal amounts of acetylene and oxygen are used, combustion is complete, the entire carbon is consumed by acetylene and the maximum thermal effect is obtained. Combustion is neutral, and this type of flame is one of the most commonly used by welders. Carbon combustion combustion, in which there is an increase in the supply of acetylene, as a result of combustion is incomplete and the amount of carbon remains unchanged. When a flame appears from a soldering tube, it is painted in a yellow tint, while in the flame two cones are enriched with carbon, but it gives out relatively little heat, and little benefit for welding. When the oxygen is supplied, when the welding source gradually increases pressure, the flame, begins to gradually take the form of a white cone. With a further increase in oxygen supply, the flame cone becomes clearly defined, although the result of carbon flame is still a little visible. Such welding is mainly used for hard materials, excluding steel, since the remainder of carbon remains in the seam and makes it brittle. Oxidizing combustion, if the supply of oxygen will continue to increase the flame, and an excess of oxygen is formed. The inner cone of the flame will become shorter and clearer, the flame will be painted in a saturated purple color, while the molten metal will be less liquid, and there will also be severe sparking. Flame oxidation is used only for special materials. With oxygen cutting, stronger decay occurs. This is due to the fact that when steel heats up in the presence of oxygen, magnetic oxide (slag) is formed. Oxygen supply rate affects the combustion rate of metal particles adjacent to the oxygen flow. Inverter semi -automatic for steel cutting requires a temperature of about 900 ° C, which is called the ignition temperature. This is below the melting temperature. Minor residues of combustion products will necessarily remain on the edges of the product, but they can be easily removed (for example, grinding). Oxygen-gas cutting is used for all types of steel, except aluminum, stainless steel and cast iron. This is an extremely quick and universal process that eliminates the risk of an accident due to its simplicity.
Types of oxygen-accelein combustion during welding
287