Many people around us are learning about the rectangular tubes around us. When using rectangular tubes, many people find that their quality is related to many aspects. When choosing rectangular tubes, people need to know specific identification methods. Through in-depth understanding, they can choose good products. What are the types of rectangular tubes? What are the methods for distinguishing rectangular tubes?
What are the steel rectangular tube sizes？
The rectangular tube models have the following specifications (in millimeters):
400 * 600 * 6.0-16,
150 * 200 * 3.0-12,
60 * 120 * 2.5-6.0,
300 * 500 * 6.0-16,
100 * 300 * 4.0-12,
60 * 100 * 2.5-6.0,
200 * 500 * 6.0-16,
100 * 200 * 3.0-12. and so on.
Rectangular tube is a square section shaped steel made from Q235 hot-rolled or cold-rolled strip or coil steel as the base material, which is formed by cold bending and then high-frequency welded. Except for wall thickness increase, the corner size and edge flatness of hot-rolled thick walled square pipes reach or even exceed the level of resistance welding cold formed square pipes.
What are the methods for distinguishing rectangular tubes?
1. The identification method for rectangular tubes is fake and inferior, and rectangular tubes are prone to folding. Folding is a variety of creases formed on the surface of rectangular tubes, which often run through the longitudinal direction of the entire product. The reason for folding is due to the pursuit of high efficiency by fake and inferior manufacturers, which results in excessive reduction and the generation of ears. Folding occurs during the next rolling process, and the folded product will crack after bending, resulting in a significant decrease in the strength of the steel.
2. The identification method for rectangular tubes is that there are often pitted surfaces on the surface of the tubes. Pitted surface is a defect caused by severe wear and tear on the rolling groove, resulting in irregular unevenness on the steel surface. Due to the pursuit of profit by manufacturers of fake and inferior rectangular pipes, rolling grooves often exceeds the standard.
3. The identification method for rectangular tubes is that the surface of fake and inferior rectangular tubes is prone to scarring. There are two reasons: (1). The material of fake and inferior rectangular tubes is uneven and there are many impurities. (2) . Counterfeit and inferior manufacturers have rudimentary guide equipment that is prone to sticking steel, and these impurities
4. The identification method for rectangular pipes is that the surface of fake and inferior materials is prone to cracks because its billet is made of adobe, which has many pores. During the cooling process, the adobe undergoes cracks due to thermal stress, and after rolling, there are cracks.
5. The identification method for rectangular pipes is that fake and inferior rectangular pipes are prone to scratches, as the equipment of the manufacturer of fake and inferior rectangular pipes is simple and easy to produce burrs, which can scratch the surface of the steel. Deep scratches reduce the strength of steel.
6. The identification method for rectangular tubes is fake or inferior. The rectangular tube has no metallic luster and appears light red. There are two reasons why it is made of adobe. The rolling temperature of fake and inferior materials is not standard, and their steel temperature is visually measured, which makes it impossible to roll according to the specified austenite area, and the performance of the steel cannot meet the standard.
7. The identification method for rectangular pipes is that the transverse bars of the fake and inferior rectangular pipes are thin and low, often resulting in insufficient filling. The reason is that the manufacturer has a large negative tolerance, and the first few layers of pressure on the finished product
8. The identification method for rectangular pipes is that the cross-section of the fake and inferior rectangular pipes is elliptical. The reason is that the manufacturer, in order to save materials, has a large reduction in the first two passes of the finished roll, which greatly reduces the strength of this type of threaded steel and does not meet the standards for the external dimensions of threaded steel.
9. The identification methods for rectangular pipes include uniform composition of high-quality steel, high tonnage of cold shear machines, smooth and neat cutting end faces, while fake and inferior materials often have meat shedding on cutting end faces due to poor material quality, which is uneven and lacks metallic luster. Moreover, due to the limited cutting of the manufacturer's products, large ears may appear at the head and tail.
What are the models of rectangular steel tubes? What are the methods for distinguishing rectangular tubes? The above content is the answer that everyone wants to know. Everyone should have a comprehensive understanding of the rectangular tube type, so as to choose the most suitable one according to their own needs, in order to better ensure that every work can be carried out well. In short, there are many models of rectangular tube types, and when choosing, one should be aware of their own needs.
Post time: Sep-25-2023
