Causes of Surface Scratches on High Frequency Welded Pipe in Factory

      In the process of producing high frequency welded pipe, the manufacturer of welded pipe will encounter the damage of the tube surface, which is due to the main cause of the guide roll and the extrusion roll.


1, the scratch produced by the guide roller usually occurs on both sides of the high frequency welded pipe, and the scratch characteristics are large and continuous.  The reasons include:
(1) the height of the guide sleeve is not correct, such as the damage of the guide roller bearing, the guide roller can not control the high frequency welding pipe well, so that the guide sleeve and friction lead to scratch.
(2) when the central roll of the guide roller deviates from the high frequency tube production line is too large, the difference between the guide sleeve and the guide roller axis is too large, resulting in scratches on both sides of the high-frequency welded pipe.


2. the scratches produced by the high frequency welding extrusion roller mainly occur at the bottom of the high-frequency welded pipe. The reasons include:
(1) the hole mismatch caused the scratch on the surface of the high frequency welded pipe. The factors of the hole inconsistency are: the damage of the extruding roller bearing, the axial movement of the extruded roller, the uneven size of the extruded roller hole, the different height position of the two extruded roller, the bending of the extrusion roll and the instability of the assembly.
(2) the height of the extrusion roll is not matched. The lower edge of the extrusion roller hole should be the same as that of the rolling line, and the height of the guide roller is determined by the thickness of the high frequency welded pipe. If the guide roller is too low, the edge of the extrusion hole will scratch the bottom of the high frequency welded pipe.
(3) the pressure of the extrusion roller is insufficient. In particular, the extrusion roll device with double roll structure, when the pressure is insufficient, the elevation angle will appear on the roller under the action of the high frequency welding tube tension, so that the hole edge R is round and the high frequency welded pipe is lower. When the extrusion roll hole R turns round, the scratches are added.