Patent ID: 6146695
Filing Date: 2000-11-14
Classification: B23K

Abstract:
Process for application of a continuous protective film (20) of a thermoplastic material to an inside surface (68) of a longitudinal weld seam (16) on metal tubes (10) which, lying against each other at the ends, are guided over a welding arm (12) of a welding machine and an attached application arm (18), where the thermoplastic material is continuous melted and applied by means of an application nozzle (44) at least over the entire width of the weld seam (16),characterized in thatthe continuously supplied thermoplastic material is preheated in the area of the application arm (18), melted and, under homogeneous liquefaction, passed to the application nozzle (44) having an outlet opening (64) of which is guided at an adjustable constant distance (a) from the inside surface of the longitudinal weld seam (16) of the metal tube (10), and the liquid thermoplastic is applied in metered quantities.