Why SSAW Steel Pipe Out-of-Round?

After the production of SSAW steel pipe, the cross-section should be round. The standard of ovality is that the large outer diameter must not be 1% larger than the nominal outer diameter, and the small outer diameter must not be 1% smaller than the nominal outer diameter.


When the port of the SSAW steel pipe appears elliptical, it cannot be connected during butt welding in the construction. So what kind of SSAW steel pipe easy to ellipse?

When the end of SSAW steel pipe have welded seam that needs fixed, it is prone to ellipse. Another reason is that the SSAW steel pipe of the butt joint plate is prone to ellipse. When pipe ends with repair welding or a large number of repair welding areas and butt joints on the pipe, the ovality of the spiral welded pipe must be measured carefully, and if it exceeds the standard then need to repair.


How to deal with the elliptical defect of the SSAW steel pipe? Usually, we use lifting jack. After measuring the small diameter, use the jack to push the small place, so that it can be last for one to five hours. After the jack is removed, the ellipticity can be measured. For the ellipse that cannot be repaired, the quality inspection should be reported in time.