Abstract: A method for producing a molten puddle on the surface of a metal workpiece to be scarfed consists of igniting a mixture of fuel gas and oxygen. The resultant flame is used for heating a steel wire to a temperature of from 900.degree. to 1450.degree. C., whereupon the steel wire is intermittently fed into a stream of scarfing oxygen to produce droplets of molten metal, which are then transferred by a flow of scarfing oxygen on to the work surface. There is provided apparatus for carrying into effect the above method, which comprises a housing having ducts for supplying a fuel gas and oxygen formed on its periphery; an additional duct for supplying a fuel gas being made in the central part of the housing; a duct for feeding steel wire is provided in the housing in coaxial arrangement with the additional fuel gas supply duct; a scarfing oxygen feeding duct formed in the housing is interposed between the oxygen supply duct and the additional fuel gas supply duct.

Abstract: A method for powder scarfing of metal resides in that combustible gas and oxygen are fed to a zone (9) of treating a metal (10) in order to form a heating flame. Then, flux is delivered by means of a flux-carrier gas, whereupon the former is separated from the latter, and the separated gas is discharged. The flux is directed to the zone (9) of treating the metal (10) in-between the jets of combustible gas and oxygen, whereupon the flux is melted in a heating flame to form a molten bath in the metal treating zone (9). An apparatus for carrying into effect the above method comprises a body (1) formed with ducts (2), (7), (13) and (16) for supplying combustible gas, oxygen and flux therethrough, which open into an outlet cavity (8) presented to the metal treating zone (9). Mounted on the body (1) is a separating chamber (18) having a gas outlet (23) and a pipeline (21) for supplying flux into the separating chamber (18) by means of a flux-carrier gas.

Abstract: A method for detecting surface and subsurface flaws in rolled products in which an indicator coating is applied to the surface of a rolled product, whereupon the coated surface is heated with high-frequency currents. The high-frequency heating produces a temperature gradient between good and defective portions of the blank, which is sufficient to bring about a thermochemical transformation of the indicator coating over the defective areas, accompanied by a change in the color of the coating in those areas. Dark spots on the light coating indicate the locations of surface and subsurface flaws. The sharp images of flaws are visible over a long period of time on the surface of the rolled product, which makes it possible to dispense with the marking of flaws. The defective areas thus identified are chipped.