The production process of HF welded pipe depends on the product type. From raw material to finished product, a series of processes are needed. The completion of these processes requires various mechanical equipment and welding, electrical control and detection devices. These devices and devices are arranged reasonably according to different process flow, and the typical process flow of HF welded pipe is described. Unwinding - strip leveling - head and tail shear - butt welding - live storage - forming - Welding - deburring - dimension - initial inspection - pipe straightening - pipe section processing - hydraulic test - flaw detection - printing and coating - finished products.
High frequency welding is a series of welding methods for workpiece metal under the condition of heat generated by continuous contact with the workpiece surface by high frequency current and the application of forging force. It is similar to ordinary resistance welding, but there are many important differences. High frequency welding of carbon steel pipe has a history of more than 40 years. High frequency welding has a large power supply, different materials, caliber and wall thickness of steel pipe can achieve a higher welding speed (higher than the maximum welding speed over l0 times). Therefore, the general steel pipe produced by high frequency welding has high productivity because of high frequency welding speed, and it is very difficult to remove burrs from the pipe, which is unacceptable for high frequency welding steel pipe at present. Chemical industry, one of nuclear industry. From welding materials, high frequency welding can be used to weld all kinds of steel pipes.
An Important Component of High Frequency Welded Pipe Production Technology
1. In the production process of high frequency welded pipe, how to ensure that the product quality meets the requirements of technical standards and customer needs, the production process of steel pipe should be affected by product quality factors.
2. The influence of raw materials on the quality of steel pipes is mainly the mechanical properties of steel instability, surface defects of steel strips and geometric size deviation. Therefore, the control of these three aspects should be emphasized.
1) Mechanical properties of steel affect the quality of steel pipes. Welded steel pipes are often used in carbon steel structures.
2) The influence of steel surface defect on steel tube quality. Surface defect is common sickle bending, wavy shape, longitudinal edge gnawing, etc. The sickle and wavy shape generally appear in the cold rolled strip rolling process, which is caused by improper control reduction.
3) The influence of geometric dimension on the quality of steel pipes. When the width of steel band is less than the allowable deviation, the extrusion force of welded steel pipes decreases, which makes the welding of steel pipes not firm, cracks or open pipes, the width of pipes larger than the allowable deviation, the welding force of welded steel pipes increases, and there are welding defects such as welds, welding or burrs at the welds of pipes.
