MONITORING DEVICE, METHOD, AND PROGRAM FOR SEAM WELDING, AND STORAGE MEDIUM

摘要

A monitoring apparatus for an electric resistance welding operation that forms a steel sheet continuously into a cylindrical shape while the sheet is transferred, and heats and melts both of a circumferential ends of the formed steel sheet converging in a V shape, and butts against each other, includes: a unit that obtains an image of a region including a Vee convergence section between both of the circumferential ends; either one of a unit that detects a contact point and a unit that detects a Vee convergence point; a unit that sets a temperature measurement region including a weld zone in which a fusion zone in an interior of the steel sheet begins to be discharged to a surface of the steel sheet; a unit that calculates a luminance level; a unit that converts the luminance level to temperature; and a unit that determines whether a temperature of the temperature measurement region is more than or equal to a predetermined lower limit value.