Abstract: Methods and apparatus for reducing the TPM level of a diesel engine exhaust stream by providing a suitable oxidation catalyst into the exhaust train. The oxidation catalyst may be incorporated into a thermal insulative coating on the inner surface of the exhaust train, particularly the exhaust manifold and exhaust pipes prior to the turbocharger. Alternatively, when the exhaust train includes a turbocharger, the catalyst can be in a separate monolithic unit between the engine and the turbocharger. The system may also include an improved diesel oxidation catalyst unit having a metal monolithic substrate. The oxidation catalyst can also be incorporated into a thermal insulative coating inside the cylinders, particularly on non-rubbing surfaces such as The invention also includes the use of a protective mullite top coat on the thermal coating. A further embodiment is the use of a stainless steel bond coat to bind the thermal coating to a metallic substrate, particularly an aluminum substrate.

Abstract: Methods and apparatus for reducing the TPM level of a diesel engine exhaust stream by providing a suitable oxidation catalyst into the exhaust train. The oxidation catalyst may be incorporated into a thermal insulative coating on the inner surface of the exhaust train, particularly the exhaust manifold and exhaust pipes prior to the turbocharger. Alternatively, when the exhaust train includes a turbocharger, the catalyst can be in a separate monolithic unit between the engine and the turbocharger. The system may also include an improved diesel oxidation catalyst unit having a metal monolithic substrate. The oxidation catalyst can also be incorporated into a thermal insulative coating inside the cylinders, particularly on non-rubbing surfaces such as The invention also includes the use of a protective mullite top coat on the thermal coating. A further embodiment is the use of a stainless steel bond coat to bind the thermal coating to a metallic substrate, particularly an aluminum substrate.

Abstract: A plasma gun has a hollow generally cylindrical anode nozzle member and coaxially disposed therein a cylindrical cathode member, the members co-acting to form an interior passage for plasma forming gas. At one end, within the body of the gun, the passage comprises an annular gas inlet chamber or plenum proximate to the cathode. Progressing in the direction of flow, the passage is defined as an annular space between the cathode and anode members and then continues through the anode nozzle member to the exterior of the gun body. Plasma-forming gas is introduced inwardly through respective inlets, tangentially and radially into the gas inlet chamber. Means are provided for selectively regulating the respective amounts of gas introduced radially and tangentially to thereby determine the degree of vortical flow of gas through the gun.

Abstract: A device for feeding metal powders suspended in a conveying gas uniformly and controllably to a point of utilization such as a flame spray gun comprising an enclosed hopper which contains the powder in particulate loose and by and large unfluidized form and is supplied in its upper portion with a controlled amount of fluidizing gas. A conduit with a downwardly opening powder intake conduit passes through the lower portion of the hopper and is supplied with a conveying gas at a pre-determined rate. The fluidizing gas passes through the mass of solids and is diffused thereby. It converges towards the orifice, suspends the powder in the vicinity of the orifice, upturning into the orifice to do so, and propels the fluidized powder therethrough into the conveying gas. The amount of fluidizing gas flow determines the amount of solids placed in the conveying gas. The fluidizing gas flow is controlled inversely responsive to the pressure at a point in the conveying gas line.

Abstract: An improvement in a process for high velocity plasma flame-spraying of a powder onto a workpiece wherein an unlit plasma gas is passed through the nozzle of a plasma flame-spraying gun at a high velocity of at least 90 meters per second and an electric arc is struck between an electrode within said gun and a portion of said nozzle and powder is fed into the resultant flame exteriorly of said nozzle and said gun, which improvement comprises increasing the deposit efficiency of the coating of the powder onto the workpiece by carrying out said process such that the power through said electric arc is at least 15 kilowatts, disposing the arc created at the exit rim of said nozzle by regulating the gas velocity, length of nozzle and diameter of nozzle bore such that said arc is established at said exit rim of said nozzle, especially a process wherein a gas back pressure is maintained within said nozzle which is greater than 1 atmosphere gauge, the ignited plasma gas has an enthalpy of at least 7000 joules/standard