Why do spiral welding pipe produce wrong edges?

During the production of spiral welding pipe, side misalignment often occurs, and there are many influencing factors. Therefore, it is necessary to analyze the causes of misalignment of spiral welding pipe and their preventive measures.

Influencing factors

1. In production practice, steel pipes are often degraded due to excessive misalignment. The sickle bend of the steel strip is the main factor causing the misalignment of the steel pipe.
   In the forming of spiral welded pipes, the sickle bend of the steel strip will continuously change the forming angle, causing the weld gap to change, resulting in seams, misaligned edges and even overlapping edges. It seriously affects the quality of the steel pipe. Therefore, the sickle bending situation of the steel strip after uncoiling is observed. The disc shear can cut off part of the sickle bend through the vertical roller and the continuity and correction of the forming angle can reduce the errors caused by the sickle bending of the steel strip during the production process. effective method.
2. The main job of the edge milling machine is to tidy both sides of the raw materials, and then to make the joints into a V-shape that is conducive to connection. Automatic submerged arc welding connects the spiral welding pipe with fewer pores, high welding penetration and few inclusions, and repairs the spiral welding pipes. The workers have brought great convenience. There is basically no repair welding on the outer surface of the spiral welding pipe and no wrong edges.

Analysis of the causes of misalignment of spiral welding pipes:

1. The problem of butt joints. When the steel strips are butted head to tail, if the connection weld reinforcement is large, you must be careful, because if it is not handled properly during forming, it is extremely easy to produce large misalignments.

2. The edge condition of the steel strip is not good, so when selecting raw materials, you must choose a guaranteed manufacturer.

3. Sometimes spiral welded pipes will be misaligned due to hard bending of the steel strip during butt jointing. This phenomenon is caused by the poor shape and dimensional accuracy of the head and tail of the steel strip when the edges are not trimmed.

4. The most important point is the sickle bend of the steel strip. This is because the spiral tube is formed. The sickle bend of the steel strip constantly changes the shape angle, causing the welding gap to change and eventually open the seam. Under such circumstances, the quality of spiral welded pipes will be seriously affected, and effective methods must be taken to solve it.

At present, there are high standards for the production of spiral welding pipes. All spiral welding pipe manufacturers have greatly improved their production equipment, and the production standard pass rate can reach 98% and above. Use complete equipment, including an edge milling machine as the complete equipment, because at present, spiral welding pipe welding is a double-sided submerged arc welding connection. In order to ensure the ideal connection effect, the edge milling machine plays an immeasurable role.