Cause Analysis of LSAW Steel Pipe Surface Crack

Surface microcracks of lsaw steel pipe impact on product quality greatly, ranging from commuted, while in retirement, especially niobium, vanadium, titanium Longitudinal most prominent, has seriously affected the improvement of product quality and finished product rate. This not only gives the enterprise has brought huge economic losses, but also restricts the development of varieties of plate production line. Longitudinal surface microcracks mainly has edge crack, longitudinal, star cracks, its causes both improper rolling process parameter control, there are abnormal production of continuous casting process, the slab cracks genetic, residual element enrichment.

Longitudinal surface microcracks severely affect product quality. Longitudinal surface micro cracks main reason is the continuous casting mold copper coating off. This aspect will lead to copper penetration into the solidified shell austenite grain boundaries, grain boundary cracks; on the other hand will be uneven due to thermal stress cracks and crack sensitivity containing titanium steel strong performance is particularly evident . Control measures: To improve the quality of mold copper, copper to prevent dew; strengthen inspection before production of slab quality and production after Longitudinal; Longitudinal protection through good casting and other measures to improve Longitudinal steel cleanliness.