The production process of high frequency welded pipe
depends on the type of product. It needs a series of processes from raw material to finished product. The completion of these processes requires a variety of mechanical equipment and welding, electrical control, and testing device. These devices and equipment can be reasonably arranged according to different process flow, and the typical process of high frequency welded pipe can be made. Process: open coil - steel strip straightening - head and tail shear - pipe butt welding - live storage - forming - Welding - removal of burr - sizing - initial inspection - pipe straightening - pipe section - water pressure test - defect detection - printing and coating - finished products.
High frequency welding is a series of welding methods to realize the metal of the workpiece under the high temperature heat generated by the high frequency current produced by the surface of the workpiece continuously and when the forging force is applied. It is similar to conventional resistance welding, but there are many important differences. The high frequency welding of carbon steel pipe has a history of 40 years. High frequency welding has a large power supply, and the different materials, caliber and wall thickness of the steel pipe can reach high welding speed (higher than l0 times the maximum welding speed). Therefore, the high frequency welding production of universal steel tube has high productivity because of high frequency and high welding speed. It is difficult to remove the burr tube, which is one of the nuclear industry which is not accepted by high frequency welded steel pipes. From the perspective of welding materials, high frequency welding can be used to weld all types of steel pipes.
An important part of the production process of high frequency welded pipe
1. in the process of high frequency welded pipe production, how to ensure the quality of the product to meet the requirements of technical standards and customer requirements, the production process of steel pipe should be affected by the quality factors of the product.
2. the main effects of the raw materials on the quality of steel pipe are the instability of the mechanical properties of steel, the surface defects of the steel strip and the deviation of the geometry size in three aspects. Therefore, the three aspects should be paid more attention to.
1) the influence of the mechanical properties of steel on the quality of steel tubes, commonly used in welded pipes with carbon steel structure.
2) the effect of steel tube surface defects on the quality of steel pipe, the common surface defects are sickle bending, wave shape, longitudinal bite, and so on. Sickle and waveform usually appear in the cold rolling strip rolling process, which is caused by improper control reduction.
3) the effect of geometry size on the quality of steel pipe when the width of the steel strip is less than the allowable deviation, the extrusion pressure of the welded pipe is reduced, the welding of the steel pipe is not strong, the crack or the opening tube, the width of the pipe is greater than the allowable deviation, the welding force of the welded pipe is increased, and the welding defects exist in the welding place, such as the tip, welding or burr.