Friction between the steel strip and other objects (such as rollers) or short strip scratches caused by poor interlaminar friction of the steel strip, and scratches caused by friction of the steel strip with the graphite roller or wool felt during annealing;

The hook strip shape appears continuously along the rolling direction of the steel strip. In the case where the re-rolled material is not padded, the defect is more likely to occur.

Quality	GB/T 11253-2007 GB/T 5213-2001	JIS G3141-2005 JIS G3101-2004	EN 10130-2006 EN 10139-1998 DIN 1623-1986	ASTM A1008 / A1008M-05
Commercial Steel	Q195	SPCC(T)	DC01/ ST12	CS TYPE A/B/C
Drawing Steel	SC1 SC2 SC3	SPCD	DC03/ ST13	DS TYPE A/B
Deep Drawing Steel	SPCE	DC04/ ST14	DDS