The role of roll adjustment in the production process of erw steel pipe

In the production process of erw steel pipe, when the roll is damaged or worn seriously, some rolls need to be replaced on the unit, or a certain quantity is continuously produced in sufficient quantity, and the entire set of rolls needs to be replaced. At this time, the rolls should be adjusted to obtain good steel pipe quality. If the roll is not well adjusted, it is easy to cause the torsion of the steel pipe joint, lap welding, edge wave, embossing and scratching on the surface of the drum and the pipe body, and the ovality of the steel pipe is large. Therefore, the roll adjustment should be mastered when changing the roll. skill.

1) Replace the steel pipe specifications, generally replace the entire set of rolls. The method of adjusting the roll is to use a steel wire to pull a center line from the inlet to the outlet of the unit, and make adjustment so that each hole type is on a center line, and the forming bottom line meets the technical requirements. After changing the specifications of the rolls, the forming rolls, the guide rolls, the squeezing rolls, and the sizing rolls are firstly adjusted in a comprehensive manner, and then the closed hole type, the guide rolls, and the squeezing rolls of the forming rolls are adjusted.

2) The role of the guiding roller is to control the direction of the pipe joint of the steel pipe and the height of the bottom line of the pipe blank, alleviate the edge extension, control the rebound of the edge of the pipe blank, and ensure that the pipe joint is straight without twisting into the pressing roller. If the guide roller is not well adjusted, it is easy to cause welding defects such as torsion, lap welding and edge wave of the steel pipe joint during the welding process of the steel pipe.

3) The squeeze roller is the key equipment of the welded pipe unit. Its function is to complete the pressure welding of the pipe body whose edge is heated to the welding temperature under the pressing force of the pressing roller. In the production process, the size of the opening angle of the squeezing roller is controlled. When the pressing force is too small, the strength of the weld metal decreases, and cracking occurs after the force is applied. When the pressing force is too large, the welding strength is lowered, and the amount of external burrs is increased, which easily causes welding defects such as lap welding.

4) During the slow start of the welded pipe unit, close attention should be paid to the rotation of the rolls in each part, and the rolls should be adjusted at any time to ensure that the welding quality and process size of the welded pipe meet the specified requirements.