1. steel strip feeding: hot rolled or cold rolled steel strip is fed into the feeding system of three-roll extruder. The steel strip enters from one side and passes through the transmission device.
2. Extrusion process: When the steel strip passes through the three-roll extruder, these three rollers are called clamping roller, main drive roller and guide roller respectively. These rollers rotate and fix the steel strip with appropriate pressure. With the rotation of the roller, the gap between the clamping roller and the driving roller is gradually narrowed, and the steel strip is pushed forward at the same time. Due to the extrusion of the roller, the two sides of the steel strip are gradually bent and connected together to form a tubular structure.
3. Cooling and cutting: the extruded pipe is cooled by cooling equipment to stabilize its shape. Then, as required, the pipe is cut by a cutting machine to obtain a welded pipe with the required length. Therefore, the principle of three-roll extrusion die for high-frequency welded pipe is the above three kinds. Through the three-roll extrusion die, the shape of steel strip can be changed to form welded pipe. This method is efficient and accurate, and is suitable for large-scale welded pipe production.