Steel pipes are inseparable from human life and production activities, holding an irreplaceable position in the steel industry. From everyday utensils, furniture, water supply and drainage, gas supply, ventilation, and heating facilities to the manufacturing of various agricultural machinery, the development of underground resources, and the production of firearms, bullets, missiles, and rockets for national defense and aerospace, all rely on steel pipes.

How to distinguish between the good and bad of steel pipes?

Defective steel pipes are prone to bending. Bending refers to various folds formed on the surface of the pipe, a defect that often runs the entire length of the product. The cause of bending is due to substandard manufacturers' pursuit of efficiency, with excessive pressing, leading to ear-like deformities. During the subsequent rolling process, these deformities result in bending. The bent products will crack upon bending, and the strength of the steel will decrease.

2. Defective steel pipes often exhibit a rough surface, known as "millefiori," which is a defect characterized by irregular, uneven, and wavy surface imperfections on the steel due to severe wear of the rolling groove. As manufacturers of substandard steel pipes chase profits, they frequently exceed the rolling groove specifications.

3. The surface of inferior steel pipes is prone to scale formation. There are two reasons: (1) The material of inferior steel pipes is uneven, with a high amount of impurities. (2) The guiding and cleaning equipment of inferior material manufacturers is rudimentary, which makes it easy for the steel to adhere, leading to scale formation after these impurities are pressed by the rolling mill.

4. The steel composition is uniform, the cold cutting machine has a high tonnage, and the cutting end face is smooth and even. In contrast, counterfeit materials, due to poor quality, often exhibit a "loss of meat" phenomenon on the cutting end face, characterized by unevenness and lack of metallic luster. Moreover, since counterfeit material manufacturers produce fewer cutting ends, large ears may appear at the head and tail.

5. The trademarks and printed characters are both very standardized.

6. Large threaded steel pipes with diameters of 16mm or more, the spacing between the two trademarks is all above IM.