GB923379A - Apparatus and method for concentrically applying a powdered material to an elongated work core moving along a pass line - Google Patents

Abstract

923,379. Making composite wire; welding rods. COPPERWELD STEEL CO. May 5, 1960 [June 12, 1959], No. 15914/60. Class 83 (2). [Also in Group V] In a method of concentrically applying a powdered material to an elongated work core moving along a pass line a continuous annular layer of powdered material is fed in the direction of the pass line substantially without volumetric constriction and with the external surface of the layer retained substantially to the point at which the layer is engaged by the nip of compacting rolls, the layer being engaged by the rolls substantially as the surface-guiding terminates to compact the powder on to the core. Powdered material is discharged from a vibrated hopper 28 to an enclosed casing 31 and is fed forward to compacting rolls 13 by a helical flight 33 arranged on a rotating arbor 32. The easing 31 and a nozzle 44 attached to its forward end guide and retain the powder externally to a point adjacent the nip of the rolls. The arbor 32 is provided with a tip 49, the external surface 56 of which is so shaped in conjunction with the internal surface 55 of the nozzle 44 that the powder is fed with substantially no volumetric constriction to the nip of the rolls. The wire or rod core is fed to the roll-gap through a bore 34 in the arbor 32 which bore terminates in a precise guiding portion 34a of reduced diameter. The four rolls 13 which compact the powder about the core define a totally enclosed pass, Fig. 3 (not shown). In order to further improve the accuracy of the concentricity adjustable guide rolls 26 are provided at the exit side of the pass. The external surface of the green clad wire or rod is trued by a shaver 12 located adjacent the guide rolls 26. The rolls are lubricated with solid lubricant applied by wipers 17 and are cleaned by scrapers 18. The nozzle 44 is cleaned by air blown in through a port 57a.