Misalignment of high frequency straight seam welded pipe is the most common pre-welding problem. The misalignment of misalignment will directly lead to the degradation of steel or scrap. Therefore, pre-welding requires strict control of the amount of staggered edges. When errors occur in the whole root or semi-steel billet, they are generally due to:
1. The seam adjustment is not in place (seam edge);
2. The joint rollers are not adjusted properly (the circumferential angle of the rollers is not right, or the center line of the pipe is the axis, the left and right rollers are not symmetrical, or the radial extension of the relative rollers is not consistent), and there is no pressure turn.
3. Pre-bending is not pre-bending in place, with straight edges.


When the head or tail of the pipe is wrong, it is usually due to:
1. The position of the import and export drum is not right.
2. The center of the ring frame is not right.
3. The pressure of joint rollers is not good, and the position of individual rollers is deviated.
4. The formation is not good (the horizontal difference between the two sides after the formation of the tube is large;
5. The width of the slit is more than 150 mm.
6. Pressure fluctuation caused by hydraulic system.