1. High-quality thick-walled seamless steel pipe has uniform composition, high cold shear tonnage and smooth and tidy cutting head end face. However, due to the poor material, the end face of the cutting head often falls off, that is, it is uneven and has no metallic luster. Moreover, because the products of fake and inferior wood manufacturers are cut less, there will be big ears at the head and tail.
2. The fake thick-walled seamless pipe has no metallic luster and is reddish or pig iron-like. There are two reasons: the blank is adobe and the rolling temperature of the fake material is not standard, and the steel temperature can't be rolled in the specified austenite zone by visual inspection, so the performance of thick-walled seamless pipe can't meet the standard naturally.
3. The material of fake thick-walled seamless pipe contains many impurities, the density of steel is too small, and the size is out of tolerance, so it can be weighed and checked without vernier caliper.
4. The cross section of the fake thick-walled seamless pipe is oval, because the reduction of the first two times of the finished coil is too large to save materials, and the strength of this rebar is greatly reduced, which does not meet the standard of rebar shape and size.
5. The surface of fake thick-walled seamless pipe is easy to scar. There are two reasons: ① The material of the fake thick-walled seamless pipe is uneven and there are many impurities. (2) The guide equipment of fake and inferior material manufacturers is simple and easy to stick to steel, and these impurities are easy to scar after biting the roller.
6. The surface of fake and inferior wood is easy to crack, because its blank is adobe with many pores. Bricks crack due to thermal stress during cooling, and then crack after rolling.
The above are six ways to distinguish the quality of seamless pipes in our production and life. Only by knowing and understanding these can we choose a good seamless pipe with reasonable price produced by a good seamless pipe manufacturer.