1. False and inferior seamless steel pipes are easy to scratch, because the equipment of the fake and inferior seamless steel pipe manufacturer is crude, easy to produce burrs and scratch the steel appearance. Deep scratch reduces the strength of steel.
2. The fake and inferior seamless steel pipe has no metallic luster and is light red or similar to pig iron.
3. The transverse bars of fake and inferior seamless steel pipes are thin and low, which often presents the phenomenon of full dissatisfaction. The reason is that in order to achieve large negative tolerance, the manufacturer has a large reduction in the first few routes of waste products, a small iron profile and a full pass.
4. The cross-section of the fake and inferior seamless steel tube is elliptical. The reason is that in order to save information, the manufacturer reduces the strength of the seamless steel tube publicly and does not conform to the specification of the shape and size of the seamless steel tube.
5. Seamless steel pipe has average composition, high tonnage of cold shearing machine, smooth and uniform cutting end face, while fake and inferior seamless steel pipe often has meat loss phenomenon, that is, uneven cutting end face, and no metallic luster. And because the products of fake and inferior manufacturers cut little, the head and tail will show big ears.
6. The fake and inferior seamless steel pipe material contains many impurities, the density of the steel is small, and the size is too bad. Therefore, without vernier calipers, it can stop weighing and checking. Generally speaking, the effect of integral phase weighing is better, mainly considering the problem of cumulative error and probability theory.