In the caliber of longitudinal welded pipe production line is set welding, finishing, pipe processing, pipe casing heat treatment in one of the pipe production line. ERW steel pipe line which introduced the German SMS Meer company developed molding equipment and technology, and equipped with the world's most advanced non-destructive testing equipment, high-frequency welding equipment, heat treatment of welding equipment.
The welding of forming steel pipe is the core part of welded pipe line, the quality of welding directly determines the qualified rate of the product. With the power components and power electronics technology continues to develop, as well as heating, melting, welding equipment to promote the demand for induction, induction welding equipment technology has also been an unprecedented opportunity for development. Power components from the tube to the SCR, MOSFET to IGBT gradually adopted, induction device power, frequency is also gradually increased.
ERW pipe unit has absorbed the development experience of similar units in the world, combined with the development of the world's advanced high-frequency induction technology, using EFD IGBT-based high-power high-frequency induction welding technology. The device can be used as induction welder, can also replace the load into contact welding machine. The advantages of contact welding is high efficiency, low power consumption, but its drawback is easy to leave contact block scratches and EDM burn marks. Therefore, in view of the user's quality requirements of the continuous improvement of high-frequency induction welding in the 20th century, 90 years has been a great application.
The welding principle of the contact welding is basically the same as that of the induction welding. The difference is that the induction welding requires the coil to be set on the forming steel pipe, and the contact welding is pressing the two edges of the steel strip through the contact shoe. Induction welding current is a high-frequency current through the coil out of the current induction, and contact welding current is the direct use of high-frequency power supply current. Therefore, the contact welding efficiency is significantly higher than the induction welding, but also easy to produce contact scratches and spark burn marks.
