1. Other defects: (1) Stoppage mark; Features: The steel strip shows a clear transverse trace along the width direction due to the shutdown. Due to the sudden situation, the production line was stopped, and when it was restarted, it caused local grinding differences. Reason: Downtime. (2) Overheating characteristics: the surface of the steel strip is partially left with rust or white roughness. Reasons: One is that the production line has been shut down for too long to keep the steel belt in the furnace, and the other is that the production line is abnormal so that the speed of the steel belt is too slow. Countermeasure: Reduce downtime and ensure normal steel belt speed. (3) Under heat characteristics: The surface of the steel strip presents a brighter color. Cause: The furnace area is abnormal or the temperature is too low. Countermeasures: Ensure that the furnace temperature is normal. 2. Edge defects/edge damage, poor incisions, burrs/features: mainly due to mechanical damage to the edges of the steel belt and damage. Reasons: a. It hit the equipment due to rolling belt deviation. b. The deviation belt of the guide roller makes the steel belt contact with the electrode plate and causes the steel belt to burn. c. The material has edge loss. Countermeasure: a. Avoid skew caused by tilting of both sides of rolling mill. b. To avoid excessive side wave of the steel belt and cause #7 guide roller to be unable to guide the steel belt. 3. Roll-shaped defects (1) Protruding Wrap (2) Telescope coil characteristics: The edge of the steel coil protrudes in a stepped shape, and looks like an elongated nodal telescope. Reason: The steel sheet is left in the fixture of the mandrel so that the steel coil cannot be rolled off the line (3) Buildup characteristics: the steel coil is partially raised, and the thickness of the steel strip is thicker at a certain point, and the drum is formed after the coil is completed From the ring. Cause: The uneven wear of the hot-rolling rolls causes bad side surfaces or the folding of the head end during coiling. Countermeasures: Control the degree of wear of the roller group or pay attention to the roll shape when winding.