The identification method of fake thick-walled seamless pipe

1. And inferior thick-walled seamless steel tube is easy to fold. Folding is formed on the surface of the thick wall seamless steel tube line, this kind of defect often throughout the entire product longitudinal. Causes of fold is due to the pursuit of the false and inferior, high efficiency, large reduction, handle, when the next rolling produce folding, folding products will be cracking after bending, the strength of the large thick wall seamless steel tube.

(2) and inferior appearance often have thick wall seamless steel tube piping phenomenon. Pits was caused by groove wear thick wall seamless steel tube surface irregular uneven defects. Due to the false and inferior thick-walled seamless steel tube manufacturer to pursuit of profit, often appear the groove rolling.

(3) and inferior thick-walled seamless steel tube surface are prone to scarring. For two reasons: 1. The thick wall seamless steel tube material and inferior uneven, impurities. 2. And inferior material manufacturer guide equipment simple, easy to stick steel, these impurities after the roll bite are prone to scarring.

4. Easy generation and inferior material surface crack, the reason is that it's blank is adobe, adobe air, adobe in the process of cooling due to the effect of thermal stress, cracks, after rolling there is crack.

5. Thick wall seamless steel tube is easy to scratch and inferior reason is false and inferior material manufacturer equipment simple, easy to produce burr, scratch thick-walled seamless steel tube surface. Deep scratches to reduce the strength of the thick wall seamless steel tube.

6. And inferior thick-walled seamless steel pipe without metallic luster, reddish or similar to the color of the pig iron, two point two, its billet is adobe reasons. 2, and inferior material rolling temperature is not standard, their steel temperature is through visual inspection, so can't austenitic area of the rolling by the regulation, the performance of the thick wall seamless steel tube nature is not up to standard.

7. And inferior transverse reinforcement of thin and thick wall seamless steel tube is low, often appear phenomenon of discontent, because manufacturers to achieve big minus tolerance, finished product quantity of the previous way slants big, small iron type, groove filling.

8 and inferior thick-walled seamless steel tube cross-section oval, because the factory in order to save material, the quantity of the finished product roll before 2 slants big, the strength of rebar is greatly decreased, but also do not conform to the standard of rebar shape size.

9. High quality thick wall seamless steel tube components uniform, cold shearing machine high tonnage, cutting head end face smooth and neat, and shoddy material because the material is poor, cutting head end face often have meat, or uneven, and no metallic luster. And due to low and inferior material manufacturers cut head, end there will be a big handle.

10. And inferior thick-walled seamless steel pipe material with impurity, more steel small density, size and out-of-tolerance is serious, so in the absence of vernier caliper, can be checked to weigh it. For rebar 20, for example, maximum minus tolerance specified in the national standard of 5%, scale of 9 m in the theory of single weight is 120 kg, it should be the smallest weight: 120 X (l - 5%) = 114 kg and 114 kg weigh out the weight of the single than small, is false and inferior thick-walled seamless steel pipe, because it is minus tolerance more than 5%. In general the whole amount to match the effect will be better, mainly considering the cumulative error and probability theory to this problem.