1 steelmaking: the inner wall of the ingot mold is not cleaned, the transverse wall is out of the meat. When the bet is poured, the molten steel splashes and sticks to the transverse wall, oxidation occurs, the casting temperature is low, and sometimes the flow is interrupted. When the steel is continuously injected, the skin is turned; At the time of injection, the mold flux is improperly added, causing the molten steel to splash;

2 Rolling steel: The residual crucible on the surface of the slab is not cleaned and remains on the steel plate after rolling.

The defects are spotted, strip-like or scaly black spots, the distribution area is not the same, and the depth of the pressing is different. Such iron sheets are difficult to wash out in the pickling process, and pits are formed when the iron sheets fall off.

residual crucible cold rolled coil steel Surface Finish:

	Symbol	Remarks
Dull finish	D	A matt finish produced with a roll roughened its surface mechanically or chemically.
Bright finish	B	A smooth finish produced with a roll finished its surface smoothly

Temper Grade: Both bright annealed and black annealed available.

residual crucible cold rolled coil steel