1. Fake pipe prone to folding
Folding is the formation of the pipe surface of the various polylines, such defects often run through the longitudinal product. The reason for folding is due to the pursuit of high efficiency shoddy manufacturers, the reduction is too large, resulting in ears, the next roll when folding, folding products will crack after bending, steel strength decreased.
2. Fake pipe appearance often have Ma phenomenon
Ma surface is due to a serious groove rolling caused irregular irregularities in the surface of steel defects. Due to the fake and inferior steel pipe manufacturers to pursue profits, often the most excessive rolling mill.
3 fake steel surface easy to produce scarring, for two reasons:
(1) Fake pipe material is not uniform, more impurities.
(2) fake and shoddy manufacturers guide equipment manufacturers simple, easy to stick steel, these impurities bite roll easily produce scarring.
4. Fake and shoddy surface is easy to crack, because it is the adobe billets, adobe stomata, adobe in the cooling process due to the role of thermal stress, cracks, after rolling there are cracks.
5. Fake and shoddy steel pipe easy to scratch, because the shoddy steel pipe factory equipment simple, easy to produce burrs, scratched steel surface. Deep scratches reduce the strength of the steel.
6 shoddy steel pipe without metal luster, pale red or pig iron-like color for two reasons:
(1) Its blank is adobe.
(2) fake and shoddy material rolling temperature is not standard, and their steel temperature is visually, so can not be the prescribed austenitic region of the rolling, the performance of the steel can not be achieved naturally.
7. Fake and shoddy tubes narrow and low transverse bar, often appear dissatisfied with the phenomenon, the reason is that manufacturers to achieve large negative tolerance, the first few Road, the finished product is too large, iron is too small, the hole filled with dissatisfaction.
8. Cross-section of shoddy steel pipe is oval, because the manufacturer in order to save material, the finished product before the second roll reduction is too large, the strength of such rebar greatly reduced, but also does not meet the standard dimensions of the rebar .
9. The composition of high-quality steel uniform, cold clippers tonnage high, cut end face smooth and neat, and inferior material due to poor quality, cut end face often have the phenomenon of meat, that is uneven, and no metallic luster. And because of inferior products manufacturers cut less head and tail will appear big ears.