A MATHEMATICAL MODEL OF SHORT-CIRCUITING TRANSFER IN THE HIGH-SPEED OSCILLATING MAG PROCESS DEVELOPMENT OF AUTOMATIC MAG WELDING MACHINE WITH ARC SENSOR AND ITS APPLICATION TO FIELD WELDING OF GAS PIPELINES

摘要

This paper describes an arc sensor system for automatic MAG welding. Based on conventional mathematical models of spray transfer, a new arc sensor model of short-circuiting transfer in the high-speed oscillating (10 Hz-50 Hz) MAG process has been developed. The simulation results of short-circuiting transfer behaviour agree with the experimental results. An optimisation of the oscillating frequency, for the short-circuiting frequency, sustains to improve the sensitivity and reliability of the arc sensor. The arc sensor system based on this principle enables to keep practical accuracy for seam tracking at short-circuiting metal transfer condition, and the automatic welding machine with this sensor was applied to field welding of gas pipelines.