GB781574A - Improvements in apparatus for forming weld deposits - Google Patents

Abstract

781,574. Building un by spraying. DEWRANCE & CO., Ltd. Jan. 13, 1955 [Jan. 13, 1954], No. 983/54. Class 82(2) The annular surface of a work piece, specifically a steam valve seating, is provided with a facing deposited by spraying metal powder through a flame by means of a blowpipe mounted through the axis of the annular part and arranged for relative rotary motion of the seating and blowpipe. A valve casting 125 having a seating 126 is arranged on the machine on a turntable 2 for rotation around a blowpipe 94 which may be adjusted vertically by the control 48 working via a chain 45 and chain wheel 44. A control wheel 70 driving shaft 67 conveys motion through the bevel wheels 63, 64 and the rotary shaft 62 to move the slide 55 and the blowpipe assembly mounted thereon left or right. A motor 88 and variable-throw crank 83 reciprocates the blowpipe radially over the full width of the annular surface to be deposited. The turntable is rotated by a motor 21 through a variable speed friction drive controlled by the handle 123. A powder hopper 107 supplies the facing metal powder to an injector device (which may be as disclosed in Specifications 707,228, 707,290 and 757,711 [Group XII]) into the gas stream from a gas/air mixer 105 and along pipe line 101 to the blow-pipe 94. A gas burner 124 is used for preheating the work and subsequently maintaining the desired temperature. The valve body is first rotated rapidly whilst being preheated and then more slowly whilst the metal is sprayed on.