Why does stainless steel channel steel have surface cracks?

When we are processing stainless steel channel steel, sometimes we find that there are cracks on the surface. What is the matter? What is the cause? Large diameter plastic coated steel pipe

1. The cause of the cracks: the product has ears before the finished product; ears, flashes, severe scratches, severe wear of the roll groove, etc. generated in each process of the rolling process; clean up the blanks with serious defects improper.

2. Reasons for cracks: During rolling, there are inclusions in the molten steel, and the oxygen content is high, which produces oxides, which are not cleaned during the manufacturing process, resulting in cracks.

3. Reasons for cracks: The molten steel contains a large amount of gas. When the molten steel is solidified, the gas is discharged to form bubbles. The bubbles near the outer layer of the cast slab become subcutaneous bubbles, which are arranged vertically in a honeycomb shape under the surface of the billet. Generally, the internal bubbles can be welded after the billet is rolled. However, some subcutaneous bubbles are close to the surface. When heated, when the surface of the billet is oxidized or burnt, the subcutaneous bubbles will be exposed, oxidized, and cannot be welded. Cracks occur.