Thick-walled steel pipes: Steel pipes whose outer diameter to wall thickness ratio is less than 20 are called thick-walled steel pipes. It is mainly used as petroleum geological drilling pipes, cracking pipes for the petrochemical industry, boiler steel pipes, bearing steel pipes, and high-precision structural steel pipes 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 use cold-drawing technology, while thick-walled steel pipes generally use hot-rolling technology. If they are distinguished by units of measurement, then, it is generally believed that the wall thickness/steel pipe diameter equal to 0.02 is the dividing line between thick-walled steel pipes and thin-walled steel pipes. The wall thickness/steel pipe diameter less than 0.02 is a thin-walled steel pipe, and the wall thickness/steel pipe diameter greater than 0.02 is a thick-walled steel pipe. In terms of use, thin-walled steel pipes wall steel pipes are mostly used in steel pipelines. Thick-walled steel pipes are mostly used as blanks for hollow parts. Used on pressure-bearing and important steel pipelines.
Thick-walled steel pipes are mainly used in water supply projects, the petrochemical industry, the chemical industry, the electric power industry, agricultural irrigation, and urban construction. For liquid transportation: water supply and drainage. For gas transportation: coal gas, steam, liquefied petroleum gas. For structural purposes: piling steel pipes, bridges; steel pipes for docks, roads, building structures, etc.
The phenomenon of counterfeit thick-walled steel pipes:
1. Fake and inferior thick-walled steel pipes are prone to folding.
2. Fake thick-walled steel pipes often have pitted surfaces on the surface.
3. The surface of fake thick-walled steel pipes is prone to scarring.
4. The surface of fake and inferior materials is prone to cracks.
5． Fake thick-walled steel pipes are easy to scratch.
6． Fake thick-walled steel pipes have no metallic luster and are light red or similar in color to pig iron.
7． The transverse ribs of fake thick-walled steel pipes are thin and low, and they often appear to be underfilled.
8. The cross-section of fake thick-walled steel pipes is oval.
10. The material of fake thick-walled steel pipes contains many impurities and the density of the steel is low.
11. The inner diameter of fake thick-walled steel pipes fluctuates greatly.
12． The trademarks and printing of steel pipes are relatively standardized.
13. For large threads of three steel pipes with a diameter of 16 or more, the distance between the two trademarks is more than 1M.
14． The longitudinal bars of counterfeit steel rebar are often wavy.
15. The manufacturers of fake and inferior thick-walled steel pipes have no operation, so the packaging is loose. The sides are oval.
Thick-walled steel pipe production steps:
1. Stainless steel elbow changes the wall thickness of thick-walled steel pipes, which changes the wall thickness along the length of the steel pipe;
2. Process the square steel tube section and change the circular section into square, elliptical or polygonal shape;
3. Square steel tubes with curling and bottom sealing, square steel tubes that are curled to the outside or inside of the tube to increase the total strength of the tube end or seal the end of the square steel tube;
4. Stainless steel elbow variable diameter square steel tube, which means that the diameter of the steel pipe end or a certain part of the steel pipe is reduced;
5. Stainless steel elbows are used to bend square steel pipes. The most common contact is to turn straight steel pipes into bends with different curvature radii, such as elbows, curved steel pipes, etc.;
6. Square steel tubes with flanges and rounded edges. The former refers to the end of the tube convex inward or outward, and the latter refers to the square steel tube with bulges or grooves formed in the circumferential direction of the tube.
Post time: Apr-24-2024