Skill Flow For Straight Seam Steel Pipe Manufacturing

Today we will introduce the skill flow of straight seam steel pipe manufacturing. Take the lsaw steel pipe as an example. If a long radius straight seam pipe is used, if the pipe of the steel billet manufacturer is used, the standard should be selected first and the pipe material should be proposed. The extension rate, after theoretical accounting, usually extends between 44% and 46% and goes back. The usual elongation of a short radius of 220 mm is 60%.

After selecting the material, the material is cut according to the standard of the straight seam pipe, and then the scientific radius, for example, the straight seam pipe of 11° is calculated, and the straight seam pipe of 12° can be processed by the scientific calculation. After theoretical calculation, it can be calculated, and then the length is used as a fixed length for interception. Finally, the material is hot rolled. We can all see the rolling mill and the practice is very simple.

It is a semi-circular core or roller, the roller is thickened and thinned, and the rolling process is a process of extending the zigzag. There is support at the back, the cutting pipe section is threaded into the roller, and a rear frame is used to fix the roller. There is an electric wheel in the center, some of the electric wheels are hydraulically driven, some are driven by mechanical transmission, that is, screw drive, and then the electric wheel is rolled forward.

The electric wheel rolls the tube forward along the roller. There is an induction coil outside the roller. The tube is heated and heated. Then the electric wheel rolls the tube down and processes one. After rolling, the straight seam steel pipe is flattened in this hot state. Because some straight seam pipes are not properly handled, they will be distorted, which is not allowed. In addition, after the rolling head, the outer diameter of the head is usually large, and it is flattened by a flat die.

In practice, the flat die is a press. It must have a set of molds, two semi-circular arcs, one on each side. The outer diameter after flattening meets the scale requirements of the product. The mezzanine is manipulated by the interlayer of the material. The mezzanine of the straight seam pipe and the pipe are the same, both ± 22.6%. In the process of rolling, under normal circumstances, the interlayer should not change, but if it is due to the cause of the east and west, some local occurrences will reduce the appearance of the wall. Therefore, when the material is raised, the interlayer should be added with some margin, such as the straight seam tube is 8.28 mm. The interlayer is usually about 8.6 mm, which avoids the difference in thickness due to partial thickness reduction during coiling.

After the shape is good, the outer diameter of the straight seam tube and the sandwich scale have reached the demand. The finishing process is carried out below, and after the shot peening, the corrosion rust of the outer layer of the straight seam tube is removed, and the two ends are treated for the welding to facilitate the welding. After the selection, printing, anti-corrosion paint, forming and other processes, it can be shipped. The above is a method for manufacturing a straight seam pipe with a straight seam steel pipe as a material below 31". Exceeding 31", which is 600 mm or more in the future, the maximum straight seam pipe is between 2.042 m and 2.80 m, which is made of steel plate.

After the steel plate is cut into pieces according to demand, it is shaped like a tyc, and is punched into a circular shape by punching. There are two halves and then put together and welded. Because of the presence of welds, non-destructive testing is required. Because of the presence of welding stress, heat treatment is also required. There are two more processes for welding straight seam steel pipes: one is flaw detection and the other is heat treatment. The same as other programs.