Abstract: A thermal spray gun of the present invention is capable of forming a good-quality ceramic spray coating. According to the machine, a flame generated in a combustion chamber of the machine is sent into a passage formed from the combustion chamber and through a discharge port that communicates with the combustion chamber, and then the flame is discharged from the discharge port to outside of the machine. A spray material is fed to the flame passing through the passage so that the spray material can be softened or melted by the flame and can be jetted out. An auxiliary fuel is fed to the flame passing through the passage to increase a temperature of the flame.

Abstract: A detonation gun for thermal spraying formed by a combustion chamber (1) and a barrel (2), with entrances for fuel (5) and for oxidizer (4), one or more spark plugs (6) for detonating the fuel-oxidizer mixture and one or more injectors (7) for the introduction of the product into the barrel, the gun in the invention centers its characteristics on the incorporation of a direct injection system of the fuel and oxidizer gases into the explosion chamber, producing explosive mixtures of different compositions according to the various zones in the explosion chamber, with a constrained volume existing in this explosion chamber in which only fuel is injected in such a way that it can generate high-energy explosions, maintaining the cyclic operation of the gun.

Abstract: An electric arc metalizing apparatus includes a wire drive unit within a housing unit, a device for attaching at least two spools of wire within the housing unit such that the wire can be led through the wire drive unit, a spray gun spatially moveable with respect to the housing, the wire drive unit having at least one drive roller advancing the wire to the spray gun, the drive roller having a knurled surface engaging the wire for avoiding slippage and removing contaminations like corrosion layers, and within the housing unit at least one wire cleaning/lubrication mean position downstream from said drive unit.

Abstract: A deposit is formed on a deposition substrate using a deposition gun that bums a mixture of a fuel and an oxidizer to form a deposition gas flow, mixes a powder into the deposition gas flow to form a deposition mixture flow, and projects the deposition mixture flow therefrom. The deposition gun is provided with a flowing coolant. A flow rate of the fuel to the deposition gun, a flow rate of the oxidizer to the deposition gun, a flow rate of the powder to the deposition gun, and a cooling capacity of the coolant flow are all measured. The flow rate of the fuel, the flow rate of the oxidizer, the flow rate of the powder, and the cooling capacity of the coolant flow are all controlled responsive to the step of measurements.

Abstract: A feedstock injector for connection to a source of heated gas comprises a converging channel extending from the upstream end to the downstream end of the injector. A splitting arm extends diagonally within the converging channel, the splitting arm comprising two symmetrically opposed surfaces extending from the inlet to the outlet ends of the converging channel. A feedstock injection passage opens axially at the downstream end of the splitting arm. The gas stream discharged by the injector contacts and entrains the feedstock with improved uniformity.

Abstract: A torch for thermal spraying stored rotatably in the front portion of a nozzle and having a discharge member with a droplet passage at the center, wherein a projection is formed at the tip of the discharge member, an air jet space allowing rotating air to be blown therein is formed at the rear of the discharge member projectedly from the discharge member by integrally forming with each other a plurality of arms disposed in an air jet cylinder, and a rotating force is given to the discharge member by the air blown from an air jet port disposed on the outside of the air jet space, so as to bring the rotational speed of the discharge member into the range of 800 to 6000 rpm, whereby thermal spraying can be performed on the internal surfaces of pipes and cylinders, and the thickness of a thermal spraying film can be optimized.

Abstract: A coating material is deposited on a substrate by vacuum or low-pressure pulsed detonation coating. A detonation chamber receives a detonable mixture containing a coating precursor. The detonable mixture is ignited to produce detonation products laden with the coating precursor. The detonation products are accelerated in a low-pressure or vacuum chamber and discharged through a nozzle into contact with a substrate situated in low pressure to produce a high quality coating.

Abstract: The invention relates to the technology of applying a coating of powder materials by spraying and can be used for producing a coating of metals; their mechanical mixtures and dielectrics, adding various functional properties to treated surfaces. The proposed method of applying a powder coating comprised as follows: producing a gas-carrier flow, mixing powder with it, accelerating the gas-powder flow in the nozzle, generating its preset profile, further simultaneously generating the second gas-carrier flow, heating it, generating its preset profile and accelerating it in the nozzle, after that superimposing the accelerated gas-powder flow of the preset profile over the gas-carrier flow of the preset profile, and directing the cumulative jet to an article.

Abstract: The invention concerns a method which consists in maintaining the two ends (2, 4) of the bar (1) on the end supports (3, 5) of a frame (10), one of the ends (2) being maintained fixed, and in driving the bar in rotation. The invention is characterised in that it consists further in drawing the bar (1) while spraying a coat on the bar, the drawing of the bar corresponding to an elongation of about 0.2 to 0.001%.

Abstract: A coherent material is formed on a substrate (10) by providing a precursor suspension (14) in which particulates are suspended in a carrier fluid, and directing the precursor suspension (14) at the substrate (10) from a first source (12). Generally contemporaneously with application of the deposited precursor suspension (14) to the surface, hot gases, e.g. hot gases produced by a flame (16), are directed at the substrate (10) from a remote second source (18) to fuse the particulates into the coherent material.

Abstract: The system for injecting gas for a detonation projection gun does not incorporate mechanical closing valves or systems for the supply of combustible gas or other inert additive compounds such as nitrogen, argol, helium or the like. On the contrary, the supply of gas or compounds occurs directly and separately to the detonation chamber (1) through a series of independent passages, one for the comburant and at least another passage for the combustibles, each passage being comprised of an expansion chamber (8) and of a plurality of distribution conduits (9) having a reduced cross-section and/or extended length.

Abstract: A thermal spray or welding apparatus including a cored wire electrode with a sheath and a multiplex powder composite. The composite comprises micron-sized particles and sub-micron sized particles, including nano-scale particles, the particles mechanically cooperating to promote smooth powder flow, which facilitates compaction of the cored wire electrode. The invention also includes a method of manufacture of the apparatus including the cored wire electrode and its method of use to deposit a low porosity coating with high levels of alloyed refractory elements that is adherent and low in oxide content.

Abstract: A nozzle applies fluid (e.g., heated gas) to a solder region of a circuit board component having a set of fluid-delivery edges and a set of fluid-escape edges. The nozzle includes a top member to connect with a fluid source, and a set of fluid-delivery side members coupled to the top member. Each fluid-delivery side member extends from the top member and around a respective fluid-delivery edge of the circuit board component when the circuit board component engages with the nozzle. Each fluid-delivery side member defines (i) at least a portion of a fluid-delivery channel that extends from a vicinity adjacent the top member toward the solder region of the circuit board component when the circuit board component engages with the nozzle, and (ii) a barrier that substantially prevents fluid from escaping from the solder region along the respective fluid-delivery edge for that fluid-delivery side member.

Abstract: The apparatus is comprised of a compressed air source which is connected by a gas conduit to a heating unit whose outlet is connected to a supersonic nozzle inlet in which a supersonic portion is connected by a conduit to a powder feeder. Compressed air of pressure Po from the compressed air source by the gas conduit is delivered to the heating unit to be heated to the required temperature. The heated air enters the supersonic nozzle in which it is accelerated to a speed of several hundred meters per second. The powdered material is passed from the powder feeder by the powder feeding conduit to the supersonic nozzle portion in which it is accelerated by the air flow at section of the nozzle from the injection point to the nozzle outlet.

Abstract: The powder injection system consists of a dosage chamber directly fed by a conventional powder feeder and communicated with barrel of the detonation gun through a direct conduit. In this way, the pressure wave advancing through barrel enters the communication conduit and upon reaching dosage chamber undergoes a sudden expansion, interrupting powder feeding from the continuous feeder and causing the full fluidization of powder contained in dosage chamber. The fluidized powder is suctioned to barrel where it remains until the pressure wave generated in a new detonation cycle carries it away, depositing it on the surface of the part to be coated.

Abstract: A feedstock injector for connection to a source of heated gas comprises a first plurality of channels arranged symmetrically about a longitudinal axis, the channels leading from the upstream end to an intermediate region of the injector. A second plurality of channels, coaxial with the first plurality of channels and arranged symmetrically about the same longitudinal axis, extend from the outlet ends of the first plurality of channels towards the downstream end of the injector and converge at a convergence angle towards a common region of convergence located downstream on the longitudinal axis. Feedstock material is injected axially towards the common region of convergence.

Abstract: A robotic machine includes a robotic arm with a machine tool mounted thereto. A powder injector is mounted near the tool. A local powder feeder is mounted to the arm and includes a local conduit for supplying powder to the injector, and a load cell for measuring powder weight therein to control feedrate. A remote powder feeder is spaced from the arm, and includes a remote conduit joined to the local feeder for supplying powder thereto. A process computer controls the arm, and two feeders and effects staged delivery of the powder from the remote feeder to the local feeder for improving powder delivery response time.

Abstract: A painting machine includes a powder paint spray gun, a mixer for mixing a plurality of powder paints having different colors, and a control device controlling an amount of each powder paint supplied to the powder paint spray gun so that a mixing ratio of the powder paints is continuously changed.

Abstract: The present invention relates to a plasmatron for a plasma coating apparatus including an anode having an axial bore through which gas is passed around a cathode and an electric arc is established between the anode and cathode. A powder feed line or conduit is connected between the anode and a powder feed source. The feed line has a straight section along a portion of its length terminating at the axial bore of the anode. The straight section of feed line has a ratio of length to internal diameter at least about 4.8, preferably 10 and even more preferably 15.

Abstract: A method and apparatus for coating the outer surface of a workpiece comprises disposing a workpiece in a fixed position along an axis and rotating a thermal spray gun around the axis on a support with a thermal spray thereof directed towards the axis. The powder, fuel and oxygen are rotatably coupling to the gun and the thermal spray gun and the support are moving along the axis while rotating.

Abstract: The present invention relates to a plasmatron for a plasma coating apparatus including an anode having an axial bore through which gas is passed around a cathode and an electric arc is established between the anode and cathode. A powder feed line or conduit is connected between the anode and a powder feed source. The feed line has a straight section along a portion of its length terminating at the axial bore of the anode. The straight section of feed line has a ratio of length to internal diameter at least about 4.8, preferably 10 and even more preferably 15.

Abstract: An apparatus is disclosed for kinetic spray coating of substrate surfaces by impingement of air or gas entrained powders of small particles in a range up to at least 106 microns accelerated to supersonic velocity in a spray nozzle. Preferably powders of metals, alloys, polymers and mixtures thereof or with semiconductors or ceramics are entrained in unheated air and passed through an injection tube into a larger flow of heated air for mixing and acceleration through a supersonic nozzle for coating of an article by impingement of the yieldable particles. A preferred apparatus includes a high pressure air supply carrying entrained particles exceeding 50 microns through an injection tube into heated air in a mixing chamber for mixing and acceleration in the nozzle. The mixing chamber is supplied with high pressure heated air through a main air passage having an area ratio relative to the injection tube of at least 80/1.

Abstract: The high-velocity oxygen-fuel or air-fuel apparatus and method to apply low-oxidized and high-density coatings and bulk materials by spraying of non-fused particles, said apparatus comprises a catalytic member in internal burner. Metallic or ceramic catalyst of the catalytic member allows stable combustion at gas temperatures below the melting point of spraying material. Lowering of combustion temperature occurs when increasing the pressure and flow rate of the oxidizer or fuel over stoichiometrical or when adding an inert gas into combustible mixture. The catalytic member contains a catalyst selected from the group of noble metals, or binary oxides of the noble metal and rare earth metal, or other high temperature resistant catalyst capable to lower an ignition temperature of the oxidizer and fuel mixture.

Abstract: A rotary atomizer applies particulate paints with good color matching by reducing paint droplet size deviation and then optimizing the other paint spraying parameters. Paint droplet size parameters are reduced by using a bell cup having reduced flow deviations, including an overflow surface having a generally constant angle between a deflector and an atomizing edge.

Abstract: A feedstock injector for connection to a plasmatron or to a fuel combustion chamber comprises a plurality of major channels arranged symmetrically about a core member, the channels leading from the upstream end of the injector towards a downstream region of convergence. In a preferred embodiment of the core member, a plurality of minor channels are provided, each minor channel leading from the inner wall of a major channel towards a minor region of convergence located inside the core. A feedstock-input passage is located axially inside the core, the passage communicating at its upstream end with the minor region of convergence and opening at its lower end through the tip of the core and a feedstock-supply passage opens into the side of the feedstock-input passage. In an alternate preferred embodiment of the core member, a minor channel extends axially from the upstream end to the downstream end of the core and feedstock-supply passage opens into the side of the minor channel.

Abstract: Apparatus and process for one of flame treatment or ceramic welding, the apparatus including a single tubular lance having a tip end, a butt end, and a head portion with a central main bore provided at the tip end so that ceramic welding materials comprised of particulate material containing oxidizable particles and combustion-supporting carrier gas are introduced at the butt end, pass through the main bore and emerge at the tip end during ceramic welding; wherein the head portion further comprises at least one conduit to convey a mixture of a fuel gas and a combustion-supporting gas, each of the at least one conduit having an orifice at the tip end of the single tubular lance and being provided with a portion for introduction of fuel gas and a portion for introduction of combustion-supporting gas so that fuel gas and combustion-supporting gas introduced at the butt end combine in the at least one conduit and emerge to form a flame at the tip end of the at least one conduit during flame treatment, and wherein

Abstract: A gas feed system for detonation gun apparatus having a labyrinth shaped gas path. The labyrinth is positioned between the fuel and oxygen supply and the combustion chamber of a detonation gun. The labyrinth allows the fuel and oxygen supply to flow into the combustion and precludes and migration of the detonation wave front into the fuel supply by destroying that portion of the detonation wave front that enters the labyrinth. The labyrinth gas feed system increases safety, reliability and productivity of the detonation coating process.

Abstract: A high pressure close-coupled gas atomizing nozzle includes multiple discrete gas jet discharge orifices having aerodynamically designed convergent-divergent geometry with an first converging section communicated to a gas supply manifold and to a diverging section by a constricted throat section to increase atomizing gas velocity. The gas jet orifices are oriented at gas jet apex angle selected relative to the melt supply tip apex angle to establish a melt aspiration condition at the melt supply tip.

Abstract: The present invention discloses a thermal spray apparatus with improved thermal efficiency and wear resistance in both the nozzle and barrel combustion chamber. Specifically, disclosed herein is a thermal spray apparatus for spraying substrate coatings, comprising a high velocity oxygen fuel (HVOF) gun wherein said gun includes a combustion chamber generating heated flow therefrom and a nozzle downstream from said chamber. The nozzle and/or chamber contain a first layer of material heated by the flow, and a second layer of material which contacts the first layer when said first layer is heated. The first layer has a thermal conductivity that is lower than said second layer and preferably a lower thermal expansion coefficient. In use, the contact of the first heated layer of material with the second layer operates to remove heat from the first layer therein providing automatic/self-regulating temperature control of the HVOF apparatus.

Abstract: Heat-treatment device which includes a cooling unit comprising delivery nozzles which deliver at least one coolant, characterized in that it furthermore comprises a shielding element designed so as to maintain a gaseous shielding atmosphere around at least part of the delivery nozzles.

Abstract: A method of coating a surface using a plasma arc torch comprises directing a plasma plume externally from a discharge end of the plasma torch toward the surface, positioning a powder injector proximate the plasma plume to introduce ceramic oxide powder particles at a size less than 20 microns diameter into an outer mantle of the plasma plume so that the powder particles are confined in the outer mantle, directing first and second gas jets at the plasma plume downstream of the powder injector position and on opposite sides of the plasma plume to enhance entrainment of the injected powder particles in the outer mantle, circulating the powder particles in the outer mantle of the plasma plume for a residence time to heat the powder particles to melt them without substantial vaporization, and depositing the melted powder on the surface as a dense coating having closed porosity.

Abstract: Known thermal spray apparatus are modified to achieve thermal spray coatings of increased hardness. Thermal spray apparatus operate to develop a plasma stream for introduction to a nozzle, for eventual application to the surface of a substrate. Upon entering the nozzle, the plasma stream is passed through a plasma cooling zone defined by a plasma cooling passageway, to a plasma accelerating zone defined by a narrowed passageway that expands into a plasma/particle confining zone for the discharge of material from the apparatus. The narrowed passageway of the apparatus is cooled, and the powder material to be applied by the apparatus is introduced into the plasma stream along the cooled, narrowed passageway.

Abstract: A method of operating a flame spraying burner, having water-cooled combustion chamber and expansion nozzle arranged downstream of the combustion chamber, with a gaseous fuel and/or a liquid fuel in association with an oxidation gas, a compression air and/or oxygen, and feeding a spraying material alternatively axially through the combustion chamber into the flame jet or radially, transverse to the burner axis, through at least two opposite radial bores which introduce the spraying material into the expansion nozzle; and a flame spraying burner operated by such a method.

Abstract: Thermal spraying method and apparatus for depositing a coating onto a substrate by introducing material to be coated directly within the arc discharge area and by establishing a stable laminar plasma stream. By choosing particular parameters of the spraying method, namely electrical parameters and rate of ionizable fluid, required for establishment of plasma arc there is possible to enable efficient melting of material and conveying thereof toward the surface to be coated without spreading outside and before it is evacuated toward said substrate.

Abstract: A supersonic flame jet device includes a body having an entry portion of relatively small cross-sectional area, an expanding supersonic nozzle section and a cylindrical duct of extended length connected in series with each other. In using the device, an oxidant at high pressure is introduced into the entry passage wherein the flow is increased to sonic velocity. The sonic velocity flow of oxidant is then introduced into the passage of expanding cross-section in the direction of the gas flow while introducing a fuel to be burned into the flow of the oxidant. The velocity of flow of the oxidant or the oxidant and the fuel is then increased to supersonic velocity prior to entry into the extended duct of constant cross-sectional area where a shock is produced to stabilize flame reactions along the extended duct length whereby a supersonic flame jet will exit the extended duct.

Abstract: Known thermal spray apparatus are modified to achieve rough thermal spray coatings. Thermal spray apparatus operate to develop a plasma stream for introduction to a nozzle, for eventual application to the surface of a substrate. Upon entering the nozzle, the plasma stream is passed through a plasma cooling zone defined by a plasma cooling passageway, to a plasma accelerating zone defined by a narrowed passageway that expands into a plasma/particle confining zone for the discharge of material from the apparatus. The narrowed passageway of the apparatus is cooled, and the powder material to be applied by the apparatus is introduced into the plasma stream along the cooled, narrowed passageway.

Abstract: A stream of hot air passes from a combustion chamber through an application gun to a preheated substrate. A powdered thermoplastic is fed into the application gun. The hot air stream heats the powdered thermoplastic to its fusion temperature and transports it to the substrate.

Abstract: A coaxial single point powder feed nozzle includes an inner tube disposed coaxially within an outer tube. The inner tube has a powder inlet and powder outlet, and the outer tube has a gas inlet for receiving a shaping gas, and a single nozzle outlet. An intermediate portion of the outer tube is spaced radially outwardly from the inner tube to define an annular flow manifold therebetween which receives the shaping gas. The powder outlet is disposed coaxially with the nozzle outlet and is spaced therefrom to define an annular gas outlet for the manifold for channeling the shaping gas around the powder prior to discharge thereof from the nozzle outlet.

Abstract: A method for applying a thermal spray coating onto a substrate (24) includes the steps of providing chamber apparatus (10) including a chamber (16) having a gas flow assembly (23) that includes a gas injector (27) and a spray nozzle (30) therein for introducing, a gas and spray coating. The chamber has an adjustably sized restricted opening (18) that is continuously open to the ambient atmosphere (21) that is exterior of the chamber (16). The total gas flow is maintained from the gas flow assembly (23) at a predetermined rate based on the size of the restricted opening (18) and the amount of oxygen that is desired to be present during the spraying of the coating and thereafter until the spray coating solidifies on the substrate. Gas flow from the spray nozzle (30) is determined by optimum process parameters for coating specified materials. If the gas flow from the nozzle (30) is insufficient to provide the total gas flow, the gas injector (27) supplements the total gas flow.

Abstract: A method and apparatus are provided for operating a small diameter thermal spray gun to thermal spray a coating onto a substrate. A fuel is burned within a combustion chamber of a small diameter thermal spray gun to generate a high energy flow stream, into which a coating material is injected. The combustion chamber includes an inner sleeve with cooling ports which pass cooling air laterally therethrough. A flow nozzle directs the high energy flow stream towards the substrate. The flow nozzle transfers a heat flow from a first portion of the high energy flow stream to a second portion of the high energy flow stream, and provides a thermal barrier to retain heat within the high energy flow stream. The small diameter thermal spray gun may be tuned for operating with a wide variety of coating materials by replacing the combustion chamber inner sleeve and the flow nozzle thermal transfer member with alternative members.

Abstract: A plasma cutting torch has a torch body comprising an electrode and a nozzle, and structure for mounting and connecting the torch body. It further comprises a torch support (A) defining a first series of fluid passages (7, 8, 10, 4, 47, 50, 54) connectable to respective circuits of fluids and a first bearing surface (9); a unitary assembly of torch body (B) comprising the electrode (28, 280) and the nozzle (36) and comprising a second series of fluid passages (25, 27, 38, 39, 42, 48, 49, 55, 56) and a second bearing surface (21); and a quick coupling (D) to assemble the assembly of the torch body to the support for the torch body with the first and second bearing surfaces bearing axially against each other and with the passages of the first series communicating with the respective passages of the second series.

Abstract: A method and apparatus for thermal spraying a coating onto a substrate is provided wherein a coating material is transported within a high energy flow stream. A high energy flow stream, which includes the coating material, is generated within the thermal spray gun. A flow nozzle having a barrel directs the high energy flow stream towards the substrate. The flow nozzle includes a thermal transfer member for absorbing a heat flow from a first portion of the high energy flow stream, and transferring the heat flow back to a second portion of the high energy flow stream. Additionally, the thermal member provides a thermal barrier for retaining heat within the high energy flow stream by absorbing and retaining sufficient heat within the thermal flow nozzle so that the temperature gradient between the high energy flow stream and the flow nozzle is reduced, which reduces the amount of heat transferred therebetween.

Abstract: A flame spray device of the internal burner type has a fuel and oxidizer mixture combusted within a combustion chamber feeding products of combustion to a discharge nozzle passage of reduced inner diameter. An axially aligned metal piece injector has a centrally disposed injection bore hole positioned upstream of the combustion chamber and is provided with particles which are fed through the centrally disposed injection bore hole with the injection bore hole opening near the entrance of the nozzle passage. The metal piece terminates in a cone-shaped section with a reduced diameter end proximate to the entrance to the nozzle passage. A knife-edge terminal face is thereby produced intersecting the injector bore hole to minimize turbulence and rotation of the stream of carrier gas containing the powder exiting the injector metal piece injection hole.

Abstract: A plasma flame flowing to a substrate around a beam of melt droplets is trimmed by spraying a refrigerant on the periphery of the plasma flame in the direction which allows the refrigerant to contact with the beam of the melt droplets.

Abstract: An internal burner combusting an oxy-fuel or air-fuel mixture, or a plasma heat source providing a supersonic flame jet which when expanded to atmospheric or lower pressure is characterized by a static temperature well above the melting point of a material in particle form being sprayed by the flame jet and the step of reducing the flame jet temperature after reaching supersonic velocity to a temperature below the melting point of the material prior to feeding of the material particles into the flame jet. The jet temperature reduction may be effected by injecting directly into the flame jet stream an amount of liquid or gas fluid which will reduce the flame jet temperature by the required amount. Alternatively, the supersonic flame jet may be passed through a concentric heat exchanger bearing a coolant medium such as water to absorb the necessary amount of heat from the flame jet to reduce the flame jet temperature to below the melting point of the material.

Abstract: A flame spray gun comprising a trigger-operated valve for selectively controlling the flow of conveying air to an eductor disposed in the powder flow nozzle, thereby providing the operator with substantially instantaneous control over the powder feed rate through the gun.

Abstract: A nozzle for atomizing molten metal to provide a powder having improved yield of fine particles is disclosed. The nozzle is comprised of a gas plenum, a melt delivery tube, and an annular inner wall means within the gas plenum for delivering atomizing gas to the exit orifice of the melt delivery tube. The exit orifice of the melt delivery tube has a ratio of inside diameter to outside diameter that provides a reduced flow of liquid through the tube during atomization.

Abstract: A flame spray coating system includes a thermoplastic resin powder supply hopper, an eductor adapted to entrain powder in a stream of conveying air, a valve disposed between the powder hopper and eductor for controlling the flow of powder from the hopper into the eductor, a flame spray gun and conduits interconnected between the flame spray gun and pressurized air and combustion gas sources for delivering flows of propelling air, conveying air, powder entrained in conveying air, and a combustible gas to the flame spray gun, and an eductor control disposed on the flame spray gun for controlling operation of the valve disposed between the powder hopper and eductor. A solid circular coating pattern is created with a nozzle constructed for twirling the entrained powder and conveying air. Interchangeable combustion nozzles of different sizes allow the same spray gun to be used for different substrate conditions.

Abstract: A feed system for flame spray guns is provided that comprises a hopper with a powder storage chamber, a pressurized gas source separated from the powder storage chamber by a gas distributor board, at least one flow line providing fluid communication for the pressurized air and entrained powder between the storage chamber and a flame spray gun, a powder outlet valve on each flow line for controlling the flow of pressurized gas and entrained powder from the storage chamber into the flow line, and a purge line delivering pressurized gas to the flow line downstream of the powder outlet valve for clearing powder from the flow line after the valve is closed.

Abstract: Nozzles are provided for spraying a wetting medium into the gas flow in an activating reactor. The nozzle comprises a nozzle body having a plurality of nozzles The nozzle body is surrounded by a flexible and/or porous casing and a conduit introduces a gaseous medium into the casing. The gas can be introduced in either pulses or continuously. The gas introduced in pulses causes the casing to change its form and, where a perforated or porous casing is used, the continuous gas flow forms a protective gas film around the casing, thus removing the solid material accumulated on the casing.