1. Identify by checking the appearance. The surface of inferior seamless steel pipes is prone to scarring, which is mainly due to more impurities and uneven materials.
2. Dimensional accuracy. The inner and outer diameters of inferior small-diameter seamless steel pipes fluctuate too much. Some may also have a wall deviation phenomenon, and the wall deviation phenomenon is serious.
3. Folding. Fake steel pipes are prone to folding. Folding is a variety of fold lines formed on the surface of seamless steel pipes due to the manufacturer's pursuit of high efficiency. This defect usually runs through the entire product. The surface is pockmarked, prone to scarring and cracks, and it is even easy to scratch. There is no metallic luster and the cross-section is elliptical.
4. Material. The composition of the steel is uneven, and the end face of the cut head is not smooth and neat.

1. Inferior thick-walled seamless stainless steel pipes are more likely to fold. Folding refers to various fold lines on the surface of thick-walled seamless stainless steel pipes. This generally runs through the entire longitudinal direction of the product. The reason for the folding is that inferior manufacturers, in pursuit of efficiency, press down too much, produce ears, and fold during the next rolling. The folded product will crack after bending, and the strength of the thick-walled seamless steel pipe will drop significantly.

2. Inferior thick-walled seamless stainless steel pipes are more likely to be scratched, because the equipment and facilities of inferior manufacturers are relatively simple, which is easy to produce burrs and scratch the surface of thick-walled seamless stainless steel pipes. Deep scratches may reduce the strength of thick-walled seamless stainless steel pipes.

3. The surface of inferior seamless stainless steel pipes is more likely to crack. The reason is that the quality of the blanks is poor. Most of them are adobes, which have many pores. The adobes are cracked due to the effect of thermal stress during the cooling process, and cracks appear after rolling.

4. Scarring is easy to occur on the surface of inferior seamless stainless steel pipes because the material of inferior thick-walled seamless stainless steel pipes is uneven, there are many impurities, and generally the equipment and facilities of inferior thick-walled seamless stainless steel pipe manufacturers are relatively backward, which is easy to stick to the steel. These impurities bite the rollers and easily cause scarring.

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