Reasons for the errors of large-caliber spiral pipe: In the production of large-caliber spiral pipe, many factors have occurred on the wrong side. In production practice, the wrong side is often to leave the main pipe for downgrading. Therefore, it is necessary to analyze the causes of large diameter helical tubes and to prevent errors.


1. The bending of strip is caused by the wrong side of pipeline. During the forming process of spiral welded pipe, the inclination angle of steel strip will change constantly, which will lead to the change of weld gap, leading to the opening, staggered edge and even lateral edge. The quality of steel is seriously affected, so by controlling the vertical roll, the coil of the inclined steel strip can be cut and observed so that the disc and part of the inclined angle can be removed continuously. The purpose of controlling and correcting the forming is to reduce the inclination angle. Strips effectively produce the wrong side in the production process.


2. Due to the poor shape and size accuracy of the head and tail of the trackless trimming, it is easy to cause the wrong side of the bending of the hard butt belt.


3. When the butt weld of the head and tail of the strip is strengthened, if it is not properly handled, it may result in larger offset.


4. The poor edge of the strip is another important reason for the error.