How to identify lower stainless steel welded pipes?

Folding of stainless steel welded pipes

1. False and inferiorwelded stainless steel tubes are prone to folds. Folds are several fold lines formed on the surface of the stainless steel pipe. This defect often extends along the longitudinal direction of the entire product. The reason for the formation of folds is that counterfeit and inferior manufacturers pursue high efficiency too much, and the amount of pressure is too large, which leads to the formation of ears in the pipe, and the folds are formed during the next lamination. The folded products will crack after bending, and the strength of the stainless steel pipe will decrease markedly. The appearance of false and lower welded stainless steel pipes will have a chopped surface. The chopped surface is the uneven unevenness on the surface of the stainless steel due to the strong wear of the rolling groove.

Stainless steel welded pipe crust

2. It is easy to get scared of the surface of the fake stainless steel welded pipe. There are two main reasons for training. One is that the bottom stainless steel welded pipe material is uneven, and there are a lot of impurities. The other is that the guide sanitation equipment of manufacturers of fake and inferior stainless steel welded pipes is simple and easy to adhere to steel. These impurities are easy to form scars after biting the roll.

Stainless steel welded pipe crack

3. Cracks are easily formed on the surface of false and lower. Stainless steel welded pipes, because white is adobe, and adobe has many pores. During the cooling process, adobe undergoes thermal stress to form cracks, and there will be cracks after rolling.

Stainless Steel Welded Pipes

Stainless steel welded pipe surface

4. The surface of the bottom stainless steel welded pipe has no metallic luster and will show a light red or pig iron-like color. There are two reasons for training. One is that the white space is adobe. The other is that the rolling temperature of false and lower pipes is not standard and the temperature of the steel is measured visually. If the rolling cannot be performed according to the specified austenite area, the performance of stainless steel pipes will naturally not meet the standard.

Fake and lower stainless steel welded pipes are also easily scratched, because the production equipment of fake and inferior stainless steel welded pipe manufacturers is simple, and it is easy to form burrs, scratching the surface of the steel, and deep scratches will weaken the strength. of stainless steel pipe.

The transverse ribs of false and lower welded stainless steel pipes are thin and low, which often provokes the phenomenon of dissatisfaction. Because the manufacturer wants to achieve a large negative tolerance, the amount of reduction of the first passes of the finished product is too large, the shape of the iron is too small, and the shape of the hole is not full.

The cross section of the false and lower welded stainless steel pipe is oval because the amount of reduction of the first two passes of the finished roller is too large to save materials.

Stainless steel welded pipe specification and size

5. The negative tolerance of the lowerstainless steel welded pipeusually exceeds the regulations. The lower stainless steel pipe contains many impurities, the material density of the stainless steel pipe is low, and the size is out of tolerance. Therefore, if there is no king’s foot, it can be weighed and checked.