Abstract: A scanning apparatus is provided for scanning a stream of atomized particles comprising a pneumatic valve through which gas can be routed to one or more nozzles to give a scanning action on the stream of atomized particles which routing is externally adjustable and externally programmable.

Abstract: A stream of molten metal particles in a metal spraying apparatus is deflected from side to side by gas issuing from two nozzle blocks disposed at diametrically opposite sides of the stream. Gas is supplied to the two nozzle blocks (13) alternately under the control of a rotary valve (19) having a stator (18) and a cylindrical rotor (24). The rotor has two circumferentially extending grooves (26) whose cross-sectional area varies in predetermined manner and each of which serves to provide and cut off communication between an inlet port (21) for gas under pressure and an outlet port (23) which is circumferentially aligned with the inlet port and which leads to an associated one of the nozzle blocks. The areas of the inlet and outlet ports are each greater than the maximum cross-sectional area of the groove, so that the quantity of gas reaching the nozzles at each instant is determined by the instantaneous effective area of the groove (26).

Abstract: A method for the spray distribution of metals includes emitting a stream of molten metal particles and a gas nozzle which is rotated about the stream. The gas nozzle is inclined to the axis of the particle stream and in the direction of the stream in order to produce a required distribution of the particle stream on a workpiece.

Abstract: For uniformly coating a substrate with a spray, a stream of liquid falls past a point towards which a plurality of nozzles in a bank are all directed but at different angles. Bursts of atomising gas are sprayed through the respective nozzles in a repeated sequence, such as to cause a repeated sequence of equal durations of spray in a plurality of directions.

Abstract: Aluminum is flow-coated onto ferrous strip by reducing the hot strip in hydrogen, cooling it to 650.degree.-680.degree. C. in nitrogen and spraying molten aluminum on it such that the aluminum splats flow into each other but solidify in 0.2-0.5 seconds. The aluminum is bonded to the strip through an intermetallic layer less than quarter of the total coating thickness, the aluminum having a cast structure.

Abstract: A liquid stream 2 from a nozzle 1 is atomized and distributed over a substrate 3. The liquid falls into a downwardly angled chute 10 formed by strong gas jets focussed to a point X. An air-knife 20 directed vertically downwardly in the plane of X atomizes the liquid.Gas-knives 12 and 13 are fired alternately and apply equal but opposite deflections to the liquid, which however remains in the plane of 20. The liquid is then evenly distributed on the substrate 3, which is advanced intersecting the plane of 20.

Abstract: Metal from strip feedstock 3 is arc-deposited onto a substrate 1, being propelled when molten by a gas curtain from a slit 13. The feedstock 3 is melted in regular fashion by an arc 11 struck between it and a helical non-consumable electrode 9 rotated on its axis, which is parallel to the leading edge of the feedstock 3. As the electrode 9 rotates, the arc 11 must move along the helix to keep its shortest path, and hence is constrained to traverse the full width of the feedstock 3 repetitiously.