Electric resistance welding operation management device, electric resistance welding operation management method, and computer program

An electric resistance welding operation management device for managing an electric resistance welding operation when: heat is inputted into a cylindrically fashioned metal plate transported along a predetermined transportation direction while the side surface of the metal plate is pressed by a pair of squeeze rolls; both circumferential edge parts of the metal plate, which converge to a V-shape, are welded; and an electric-resistance-welded steel pipe is manufactured. The electric resistance welding operation management device includes: an image input means for inputting a plurality of images including the V-shaped converging region; a first position detection means for detecting the position of the geometric V-convergence point (V0) on the basis of the images; a second position detection means for detecting the position of a V-convergence point (V1), which is an abutting point, on the basis of the images; a welding point position derivation means for deriving the position of a welding point on the basis of