Surface defects and causes of seamless steel pipes

The causes of surface defects of seamless steel pipes are complicated. There are hundreds of influencing factors listed. Sometimes the same defect has dozens of factors, and the defects are closely related to the type of steel. This is why the production of seamless steel pipes is complicated.

Generally speaking, it is caused by the following aspects:

1. Raw materials: poor internal organization will cause internal folding, internal cracks in the pipe wall, delamination, etc.; poor surface quality of raw materials will cause external folding;

2. Process operation: improper heating will cause internal folding, external folding, internal cracks in the pipe wall, delamination, uneven wall thickness, etc.; improper tooling processing, materials, adjustment, and use will cause internal and external folding, uneven wall thickness, internal and external threads, pits, etc.

3. Equipment: The equipment is mainly caused by poor equipment performance, looseness, collision, and scratching, etc., which cause internal folding, external folding, uneven wall thickness, internal and external threads, collision, and scratching.

In daily life, the factors that cause the defects and production process of the steel pipe can be analyzed, and then the specific reasons can be judged in combination with the production site.