Fuzzy Control for High Frequency Tube Welding System

Abstract

The field of application of electric resistance welded (ERW) tubes continues to expand these days, and the quality requirements are becoming more sophisticated from year to year. In order to meet these market conditions, more advanced technology for forming and welding is essential to ERW tube production, in addition to improvement of the quality of materials. Heat input control in welding especially plays a very important role in advancing and stabilizing the quality of ERW tubes. Various engineering processes related to heat control have been studied and developed. From the manual control in early days through PID feedback control to joint feedforward and feedback control based on computerized mathematical models — this sums up the development of heat control to this day. Mill lines today, however, must turn out a greater variety of ERW tubes of superior quality. The heat control functions and performance required for this purpose have been increasingly difficult to come by with the conventional computer control.