The phenomenon of inferior steel pipes in thick-walled steel pipes

Thick-walled steel pipes refer to steel pipes whose outer diameter and wall thickness ratio is less than 20 as thick-walled steel pipes. Mainly used as petroleum geological drilling pipe, cracking pipe for the petrochemical industry, boiler pipe, bearing pipe, and high-precision structural pipe for automobiles, tractors, etc.

The big difference between thick-walled steel pipes and thin-walled steel pipes is the thickness of the steel pipe wall. Generally speaking, thin-walled steel pipes are cold-drawn technology, while thick-walled steel pipes and thick-walled steel pipes generally use hot-rolling technology, if they are distinguished by units of measure. , then, it is generally believed that the wall thickness/pipe diameter equal to 0.02 is the watershed between thick-walled steel pipes and thin-walled steel pipes, those with wall thickness/pipe diameter less than 0.02 are thin-walled steel pipes, and those larger than 0.02 are thick-walled steel pipes. In terms of use, thin-walled steel pipes Wall steel pipes are mostly used on pipes. Thick-walled steel pipes are mostly used in blanks for hollow parts. Use on pressure-bearing and important pipelines.

Thick-walled steel pipes are mainly used in water engineering, the petrochemical industry, the chemical industry, the electric power industry, agricultural irrigation, and urban construction. For liquid transportation: water supply, drainage. For gas transportation: gas, steam, liquefied petroleum gas. For structure: for piling pipe, for bridge; for wharf, road, building structure, etc.

The phenomenon of fake and inferior thick-walled steel pipes:

1. Fake and inferior thick-walled steel pipes are prone to folding.

2. Fake and inferior thick-walled steel pipes often have pockmarked surfaces.

3. Fake and inferior thick-walled steel pipes are prone to scarring on the surface.

4. Fake and inferior materials are prone to cracks on the surface.

5. Fake and inferior thick-walled steel pipes are easily scratched.

6. Fake and inferior thick-walled steel pipes have no metallic luster and are light red or similar to pig iron.

7. The transverse bars of the fake and inferior thick-walled steel pipes are thin and low, and the phenomenon of filling and dissatisfaction often occurs.

8. The cross-section of the fake thick-walled steel pipe is oval.

10. The material of fake and inferior thick-walled steel pipe contains a lot of impurities, and the density of the steel is too small.

11. The inner diameter of fake and inferior thick-walled steel pipes fluctuates greatly.

12. The trademark and printing of the tube are relatively standardized.

13. For large threads with a diameter of more than 16 steel pipes, the spacing between the two trademarks is above IM.

14. The longitudinal bars of the fake and inferior steel rebar is often wavy.

15. Fake and shoddy thick-walled steel pipe manufacturers do not have traffic, so the packaging is loose. The sides are oval.