GB466782A - Apparatus for and method of spraying molten metal - Google Patents

Abstract

466,782. Spraying molten materials. GILLORD CORPORATION. Dec. 3, 1935, No. 33525. Convention date, Dec. 5, 1934. [Class 69 (iii)] In apparatus for spraying molten material especially steel or other metals of high melting point, the material is fed in the form of wire to a melting and spraying nozzle, the nozzle system containing a combustion and melting chamber 12, Fig. 6, to which a premixed combustion mixture is supplied under pressure and means are provided for surrounding the melted material in the combustion chamber with a continuous tubular sheath of mixed gases for conveying the melted material out of the chamber, the enveloping gases. being premixed within the apparatus. The nozzle system comprises a body 7, Figs. 6 and 7, provided with ports for the various gases and a central hole in which is screwed a guide tube 24 for the wire carrying the wire nozzle 26. The tube 24 is flanged, the flange forming with a recess in the body 7 a mixing chamber 41 for a combustible gas such as acetylene and a comburent such as oxygen. One of these gases is admitted through a port 31 controlled by a hollow valve 37 and the other through an axial passage in the valve 37 controlled by a screw valve. The mixing chamber is provided with a ring 39 having angularly-directed passages 40 therein by which the gases are mixed. The mixed gases pass through passages 43 to a chamber 29 formed between the wire nozzle 26 and a tube 21 and escape to the combustion chamber by way of grooves 28 on the outer surface of the nozzle 26. The gas envelope may consist of a mixture of air and a reducing gas such as hydrogen or a hydrocarbon. These gases are supplied through ports 17, 18 to a series of chambers formed between the body 7 and a nozzle 14 screwed therein and escape between the conical end of this nozzle and the inner surface of the combustion chamber 12. The gaseous envelope is delivered through a passage 11 shaped at its end to form a relatively straight tubular passage 11<1> for directing it against the inner surface of the chamber 12 in order to cool it, cooling being assisted by flanges formed thereon. An additional annular jet of gas may be delivered through passages formed between the nozzles 21, 14. The wire is fed to the nozzles by a constant-speed electric motor 1, Figs. 1 and 3, the rate of feed being controlled by cones 44, 45, Figs. 1 and 11. In order to use wires of different sizes, the upper cone is fixed to a driven shaft 44, while the lower cone has limited axial movement against the action of a spring bearing against a disc 52. The disc 52 carries lugs 53 engaged by a fork attached to a spring lever 56 retained in position by a tooth engaging a rack 57. The wire is led to the cone through a guide 58, Fig. 12, mounted on a rack 59 engaged by a pinion 61 operated by a handle 63 and locked in position by a knurled nut 80. From the cones the wire is led to the nozzle through a funnel 77, a door 78 being provided in the casing 5 giving access thereto. The air, gas, oxygen and additional gas and air are supplied through separately regulable valves 69, Figs. 4 and 5, and means are also provided by which all may be simultaneously cut off. This comprises a cork in each supply pipe held open against the tension of a spring 74 by a U-shaped lever 75 pivoted at 73 to the underside of the casing 2. This lever is connected with a lever 73 by a link 76, the point of which is slightly beyond the centre, but on a slight movement of the lever 75 the cones are unlocked and the spring 74 turns the lever 73 over to close all valves simultaneously.