The Strip Width Deviation Affects the Quality of Welded Steel Pipe

Frequency welded pipe production process, affecting the quality of the elements have more than one pipe, the main raw materials, welding technology and roll count which is beginning to adjust.

Key to look at raw geometric dimensions. Strip geometry affect the quality of the steel strip width when less than the allowable deviation, the extrusion pressure welded steel pipe is reduced, making the pipe weld welding is not strong, cracks or open tube. When the width of the strip is greater than the tolerance, the pressing force is increased when the welded steel pipe, steel pipe welds appear beak, lap welding and other welding defects or burrs. Therefore, the fluctuation width of the strip, not only affects the accuracy of the outside diameter of the steel pipe, but also seriously affect the surface quality of the steel pipe.

Requirements for the same section thickness difference does not exceed the predetermined value of the steel pipe, which requires a high degree of uniformity of the wall thickness of steel pipe, fluctuations in the thickness of the strip, the same volume will be transferred to the wall thickness of the permissible value of finished steel strip thickness difference exceeds the difference so that a large number of steel thickness exceeds the allowable deviation and sentenced to waste. Fluctuations in the thickness of the finished steel thickness only affects the accuracy. Meanwhile, since the strip thickness varies, the steel pipe during welding, extrusion pressure and welding temperature instability, resulting in unstable weld quality steel welding.

In addition, since the internal steel sandwich material defects exist, impurities, such as trachoma, is a major factor affecting the quality of steel. Therefore, before steel welding, to check each roll strip surface quality and geometry of the strip quality does not meet standards, not production, so as to avoid unnecessary losses.