A metal forming technique is known as a Drawn over mandrel. It all starts with a formed tube that has been electrically resistance welded (ERW). The ERW is drawn cold through a die and over the mandrel's sides. The Outside Diameter (OD) is determined by the die size and angle, whereas the Inside Diameter (ID) is determined by the Mandrel Plug. Multiple treatments follow, further shaping and refining the finish and mechanical qualities required for its eventual use.
DOM process:
Making DOM tube starts in the same way that every other electric resistance welded tube does. Steel coils are first slit to the desired tube size. The edges are then joined together with pressure by an electric resistance welder, forming the appropriate tube shape. After that, the tube is inspected to confirm that it meets industry requirements before being cut to shape and size. The normal ERW steel tube would be finished here, but DOM tubing takes it one step further. After completing the ERW steps, the entire flash weld is removed and the pipe is cold drawn on a mandrel, hence the name Drawn over Mandrel tube. Renewed treatment of the metal at a cooler temperature improves the shape, orientation, and lengthens it. As a result of the DOM process, the steel tube becomes remarkably adaptable and durable, making it the premium choice for a multitude of mechanical applications.
