1. Shoddy steel pipe prone to folding.

Folding is the formation of a variety of steel pipe surface line, this defect often runs through the entire product vertical. The reason for folding is due to the pursuit of high efficiency shoddy manufacturers, the amount of pressure is too large, resulting in ears, the next rolling to produce folding, folded products will break after bending, steel strength decreased.

2. Shoddy steel pipe surface often have Ma surface.

Ma surface is due to rolling groove wear caused serious irregular irregularities of steel surface defects. As the shoddy steel pipe manufacturers to pursue profits, rolling groove rolling is often the most excessive.

3. Fake steel pipe surface prone to scarring.

There are two reasons: (1). Shabby steel pipe material is uneven, many impurities. (2). Shoddy material manufacturers Guiding poorly equipped, easy to stick steel, these impurities bite after the roll is easy to produce scarring.

4. Pseudo-inferior material surface is easy to produce cracks, because it is a blank billet, adobe porous, adobe in the cooling off

Process due to the role of thermal stress, resulting in cracks, after rolling there are cracks.

5. Shoddy steel pipe easy to scratch, because the shabby steel pipe manufacturers simple, easy to produce glitches, scratch the surface of steel. Deep scratches reduce the strength of the steel.