Large-diameter spiral steel pipe is a general term, generally referring to spiral steel pipes (SSAW steel pipe) with a diameter greater than 1 meter. Spiral steel pipe is a welded steel pipe made of steel strips that are bent and then welded. Steel pipes need to undergo hydraulic pressure, bending, flattening and other experiments, and have certain requirements for surface quality. The delivery length is usually 12 meters, and delivery to fixed length is often required.
During the production of large-diameter spiral steel pipes, edge misalignment often occurs, and there are many influencing factors. In production practice, steel pipes are often degraded due to wrong edges and excessive tolerances. Therefore, it is necessary to analyze the causes of misalignment of large-diameter spiral steel pipes and their preventive measures.
1. 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. Seriously affects the quality of steel pipes. Therefore, observing the sickle bending condition of the steel strip coil after uncoiling, controlling the vertical roller so that the disc shear can cut off part of the sickle bend, and continuously controlling and correcting the forming angle are effective ways to reduce the misalignment of the steel strip sickle bending during the production process.
2. Due to the poor shape and size accuracy of the head and tail of the untrimmed steel strip, it is easy to cause the steel strip to bend hard and cause misalignment during docking.
3. When the weld reinforcement of the head-to-tail butt welding of the steel strip is large, if it is not handled properly during over-forming, it is easy to cause large misalignment.
4. The poor edge condition of the steel strip is another important reason for the wrong edge.
Large-diameter spiral steel pipes are mainly used in water supply projects, petrochemical industry, chemical industry, electric power industry, agricultural irrigation, and urban construction. Therefore, it is necessary to analyze the reasons for the misalignment of steel pipes and take preventive measures to ensure the weld quality of large-diameter spiral steel pipes.
During the production of large-diameter spiral steel pipes, edge misalignment often occurs, and there are many influencing factors. In production practice, steel pipes are often degraded due to wrong edges and excessive tolerances. Therefore, it is necessary to analyze the causes of misalignment of large-diameter spiral steel pipes and their preventive measures.
1. 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. Seriously affects the quality of steel pipes. Therefore, observing the sickle bending condition of the steel strip coil after uncoiling, controlling the vertical roller so that the disc shear can cut off part of the sickle bend, and continuously controlling and correcting the forming angle are effective ways to reduce the misalignment of the steel strip sickle bending during the production process.
2. Due to the poor shape and size accuracy of the head and tail of the untrimmed steel strip, it is easy to cause the steel strip to bend hard and cause misalignment during docking.
3. When the weld reinforcement of the head-to-tail butt welding of the steel strip is large, if it is not handled properly during over-forming, it is easy to cause large misalignment.
4. The poor edge condition of the steel strip is another important reason for the wrong edge.
Large-diameter spiral steel pipes are mainly used in water supply projects, petrochemical industry, chemical industry, electric power industry, agricultural irrigation, and urban construction. Therefore, it is necessary to analyze the reasons for the misalignment of steel pipes and take preventive measures to ensure the weld quality of large-diameter spiral steel pipes.
