procedures for the implementation of a thermo chemical surface launches a werkstueckes from iron

摘要

A method for making an instantaneous thermochemical start on the surface of a ferrous metal workpiece, comprising the steps of: (a) contacting a preselected spot on said surface where the reaction is to begin, with the end of a ferrous metal wire which has been heated to its ignition temperature in an oxygen atmosphere, (b) impinging a high intensity jet of oxygen gas on said surface at a point 1 to 15 cm. behind said spot, thereby causing an immediate scarfing reaction to begin and a molten puddle to form at said spot, and (c) continuing the impingement of a high intensity jet of oxygen on said puddle until the puddle has spread to a preselected width. Thereafter, the spreading oxygen stream may be left on and used to carry out the scarfing reaction, or it may be turned off and another oxygen stream may be impinged on the spread puddle at an acute angle to the work surface in order to "take over" and carry out the scarfing reaction. The type of scarfing cut sought will determine the type of scarfing oxygen stream used to "take over" the scarfing reaction from the spreading stream.