Electric Resistance Welded Tubes - An Overview Electric resistance welding, simply ERW, is a process of welding. In this process, metal parts with contact are heated by an electric current and then melted at the joint. This is done to permanently join the metal parts with each other. Electric resistant welded tubes are widely used. For instance, in manufacturing steel pipes and in assembling bodies of automobiles. Types of Electric Resistance Welding The process of electric resistance welding is further classified into several categories. These categories are based on the weld’s geometry and the method with which pressure is applied to the joints. The main types of electric resistance welding are: ● ● ●
Spot welding Seam welding Low-frequency electric resistance welding
Let us study them in detail. Spot Welding This welding is a resistance welding process used for joining two or more metal sheets that are overlapped. However, many other components go through this welding. For instance, projections, studs, electrical wiring hangers, heat exchanger fins, and of course, tubes. Generally, welding equipment and power sources are fixed with specific sizes to match the thickness and material type. Seam Welding Resistance seam welding is a welding process for producing a weld on the faying surfaces of two or more related metals. The seam might be an overlap joint or a butt joint. This is normally an automated process. It is different from flash welding such that flash welding usually welds the whole joint in one go. Whereas, seam welding starts from one end and forms the weld gradually. Low-Frequency Electric Resistance Welding Electric resistance welded pipe, that is, ERW pipe is made by cold-forming a cylindrical shape from a sheet of steel. Then, the current is passed through the two ends of the steel sheet. This is done to heat the steel to a particular point that forces the edges together. This ends up forming a bond without any use of filler material that is typically used in welding. Benefits of Manufacturing Electric Resistant Welded Tubes 1. 2. 3. 4. 5.
During the formation of the molten core, a plastic ring surrounds it every time. Plus, the molten metal does not come in contact with the air, so it simplifies the metallurgical process. The heat is properly focused and the heating duration is short. Therefore, the area affected by heat is small. In addition, the stress and deformation are also less. The use of filler metals like electrode and welding wire is not required. Also, welding materials like hydrogen, oxygen, and acetylene are not needed. Therefore, the cost of welding is low. The welding operation is simple, the mechanism is easy to achieve with automation. Overall, it improves the working conditions. This welding process offers high productivity. As there is no harmful gas or noise, it is easy to start mass production.
All these benefits are the reasons why electric resistance welding is getting more and more popular in the manufacturing industry. Dewas Metal Sections Ltd. has been helping various industries by providing high-quality components and metal elements. They are one of the leading manufacturers of metal sections in India.