MACCHINA PER LA SALDATURA DI TESTA A RESISTENZA DEI TUBI

A machine receivable within pipes to be resistance butt welded includes an elongate housing on which are mounted a welding transformer, clamping mechanisms for centering and securing the pipes, the latter being electrically connected to the transformer, and a flash and upset mechanism for axially advancing the pipes toward each other during welding. Each clamping mechanism includes a pair of members mounted on the housing to be axially movable relative to each other by an actuator. Spaced around these members and connected to them by inclined pivotal linkages to provide relative radial movement are longitudinally extending, clamping bars carrying a pair of shoes at each end. A connecting link is pivoted at each end of the bar between the shoes, while the central region of the bar is flexible within elastic deformation limits.