Three orbital welding methods and their advantages and disadvantages

Orbital welding: The technology must be very familiar to all of us. The welding technologies of seamless orbital welding equipment mainly include resistance welding, spiral submerged arc welding and longitudinal submerged arc welding. Here are three orbital welding methods and their advantages and disadvantages. The welded pipes designed and produced by these three different processes have different positions in the field of applied research due to their different raw materials, molding processes, diameters, enterprises and quality of life. However, judging from the economic development situation, my country's new production capacity for large-diameter welded pipes above 273mm has been too concentrated in recent years. There are 8 sets of JCOE (UOE) and 6 sets of 508~610mm ERW units that have been put into production or are about to be put into production, all of which are contemporary imported from China. In order to adapt to the needs of this new type of seamless line with the world's advanced scientific and technological education equipment and technology, rail welding environment problems have arisen for rails. At present, the commonly used methods in the orbital welding process include flash contact welding, gas pressure welding and thermite welding. The following is a comparison of information required for these three welding working methods.

First, flash contact welding is mainly used in various rail welding factories, because factory welding can ensure the welding quality of the rails. When welding in the factory, the 100m long fixed rail rails are usually placed on a specific machine and then heated according to the principle of the thermal effect of electric current. When the track is heated to a plastic state, it is then extruded at very high speeds. The advantage is that the rail welded by this method has the same strength as the base material, has a smooth surface, and is easy to polish and shape. The disadvantage is that this method has certain limitations.

Second, the heat generated by the reaction of acetylene gas and oxygen is mainly used for welding rails. Like flash welding, when the rails are heated to a plastic state, the rails are subject to pre-applied pressure. Two rails are welded by pressing them together. This welding method is generally suitable for outdoor workplaces. Due to the interference of the external environment, the welding quality is much lower than flash contact welding and is usually not used as a subsequent means. The advantage is that it is convenient and suitable for outdoor work.

The third is thermite welding. The same pressure welding method can also be used on outdoor construction sites. The principle of welding is to utilize the oxidation-reduction effect of iron and aluminum. During the oxidation process, a large amount of heat will be released, and the resulting molten iron will weld the two rails together.