Parameters control system for all-position welding of pipeline

Reasonable matching and effective control of various welding parameters is one of the problems in the automation of all-position welding process for circular seam of pipeline. Integrating the techniques of path teaching, parameters matching and parameters control, the automatic control system of all-position welding process for circular seam of pipeline is developed. The working principle, system structure and software design are also introduced. According to the welding position, the system can automatically assign the welding parameters, such as welding current, arc voltage, welding speed, torch swing speed and width. By adjusting wire feed rate and the torch height, the PID control of welding current and fuzzy control of arc length are realized. This system has also the functions of off-line programming, path teaching and remembering weld tracking. Applying this system to all-position welding process for circular seam of pipeline, the automatic control of root weld, filled weld arid cover weld are realized. Experiments show that the practical value of welding parameters fit the preset value very well and the weld formation is satisfied.