LASER WELDING OF THIN-WALL PIPES Russian patent published in 2014 - IPC B23K26/14 

FIELD: process engineering.

SUBSTANCE: invention relates to laser welding and may be used in various branches of machine building. Pipe edges to be welded together are subjected to laser beam effects. Argon with temperature of minus 200°C is fed to welding zone to cool down said edges. Note here that in welding the entire case of welding fixture is cooled to minus 200°C by feeding and continuous circulation of liquefied nitrogen in fixture circuit. Laser welding is conducted in continuous laser radiation mode till deep penetration of pipe edges and at continuous translation of the pipe in welding fixture horizontal axis. Pipe laser welding rate is selected subject to time and depth metal penetration under action of laser beam.

EFFECT: higher welding rate, sufficient quality of pipe penetration, homogeneous weld.

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