1. Shoddy walled
seamless steel pipe prone to folding. Walled seamless steel folding is formed on the surface of various polyline, this defect is often longitudinally throughout the entire product.
2. Thick-walled seamless shoddy appearance often pockmarked face phenomenon. Pock is due to badly worn groove walled seamless surface irregularities caused by uneven defects.
3. Shoddy thick-walled seamless surface is easy to produce scarring.
4. Shoddy material surface is easy to produce cracks because its blank is adobe, adobe many pores, adobe in the cooling process due to thermal stress, cracks, after after rolling there crack.
5. Shoddy walled seamless steel pipe easily scratched because of shoddy material manufacturers poorly equipped, easy to produce burr, scratching the surface of the thick-walled seamless steel pipe. Depth scratch reduce walled seamless steel pipe strength.
6. Shoddy walled seamless steel pipe without metallic luster, pale red or similar color of pig iron, there are two two reasons, it is blank adobe.
7. Shoddy thick-walled seamless cross ribs thin and low, often sufficient dissatisfaction phenomenon, because manufacturers to achieve large negative tolerance, finished the first few tracks reduction is too large, iron-type small, pass sufficient dissatisfaction.
8. Thick-walled seamless steel pipe shoddy oval cross section, because manufacturers in order to save material, before two of the reduction of finished roll is too large, the strength of this steel is greatly decreased, and does not comply with rebar Dimensions standards.
9. High-walled seamless steel pipe of uniform composition, high cold shear tonnage, smooth and neat end face of the cutting head, and shoddy materials due to the poor material, cut the first end surface there are often off the meat of the phenomenon that is uneven, and no metallic luster .
10. Thick-walled seamless steel pipe shoddy material containing impurities, the density of steel is small, and size tolerance serious, so without a vernier caliper case, you can check it weighed.
11. Shoddy walled seamless steel pipe diameter size fluctuations.
12. High-quality materials and printing trademarks are fairly standard.
13. Three walled seamless steel pipe diameter of 16 or larger thread spacing between the two trademarks are over IM.
14. Shoddy thick-walled seamless steel longitudinal reinforcement often wavy.
