Abstract: The cylinder walls of light metal engine blocks are thermally spray coated with a ferrous-based coating including aluminum using an HVOF device. A ferrous-based wire is fed to the HVOF device to locate a tip end of the wire in a high temperature zone of the device. Jet flows of oxygen and gaseous fuel are fed to the high temperature zone and are combusted to generate heat to melt the tip end. The oxygen is oversupplied in relation to the gaseous fuel. The excess oxygen reacts with and burns a fraction of the ferrous-based feed wire in an exothermic reaction to generate substantial supplemental heat to the HVOF device. The molten/combusted metal is sprayed by the device onto the walls of the cylinder by the jet flow of gases.

Abstract: A nozzle assembly for a HVOF thermal metallic spray coating system includes an inner tube, a middle tube and an outer tube which are concentrically arranged about an axis of the nozzle assembly and are spaced to provide annular, concentric gas flow passages for oxygen and gaseous fuel along with a central wire feed passage in an efficient, compact arrangement. A slotted nib and plug are fitted to the discharge end at the assembly and defined, together with the middle tube, an annular premix chamber for the combustible gases, and a plurality of circumferentially spaced mixing slots and a downstream mix end portion of the nib where complete mixing of the gases occurs prior to entry into the combustion chamber provided in an air cap. An annular passage between the air cap and outer tube communicates with a high pressure air source for establishing an envelope of air against the inside surface of the air cap to serve as a protective barrier layer from the atomized metal.

Abstract: An engine piston compression ring designed to reduce the negative effects of ring end butting and reduce blowby. The compression ring has a gap forming an angle with a longitudinal axis of the ring or with a radius drawn from the axis. A relieved portion is provided along the upper or inner side of the ring adjacent one end, depending upon the direction of the gap angle. The relieved portion slopes along the upper or inner side toward the one end where the longitudinal thickness of the ring is smallest.

Abstract: An engine piston compression ring designed to reduce the negative effects of ring end butting and reduce blowby. The compression ring has a gap forming an angle with a longitudinal axis of the ring or with a radius drawn from the axis. A relieved portion is provided along the upper or inner side of the ring adjacent one end, depending upon the direction of the gap angle. The relieved portion slopes along the upper or inner side toward the one end where the longitudinal thickness of the ring is smallest.

Abstract: A nozzle assembly for a HVOF thermal metallic spray coating system includes an inner tube, a middle tube and an outer tube which are concentrically arranged about an axis of the nozzle assembly and are spaced to provide annular, concentric gas flow passages for oxygen and gaseous fuel along with a central wire feed passage in an efficient, compact arrangement. A slided nib and plug are fitted to the discharge end at the assembly and defined, together with the middle tube, an annular premix chamber for the combustible gases, and a plurality of circumferentially spaced mixing slots and a downstream mix end portion of the nib where complete mixing of the gases occurs prior to entry into the combustion chamber provided in an air cap. An annular passage between the air cap and outer tube communicates with a high pressure air source for establishing an envelope of air against the inside surface of the air cap to serve as a protective barrier layer from the atomized metal.

Abstract: The cylinder walls of light metal engine blocks are thermally spray coated with a ferrous-based coating using an HVOF device. A ferrous-based wire is fed to the HVOF device to locate a tip end of the wire in a high temperature zone of the device. Jet flows of oxygen and gaseous fuel are fed to the high temperature zone and are combusted to generate heat to melt the tip end. The oxygen is oversupplied in relation to the gaseous fuel. The excess oxygen reacts with and burns a fraction of the ferrous-based feed wire in an exothermic reaction to generate substantial supplemental heat to the HVOF device. The molten/combusted metal is sprayed by the device onto the walls of the cylinder by the jet flow of gases.

Abstract: The cylinder walls of light metal engine blocks are thermally spray coated with a ferrous-based coating including aluminum using an HVOF device. A ferrous-based wire is fed to the HVOF device to locate a tip end of the wire in a high temperature zone of the device. Jet flows of oxygen and gaseous fuel are fed to the high temperature zone and are combusted to generate heat to melt the tip end. The oxygen is oversupplied in relation to the gaseous fuel. The excess oxygen reacts with and burns a fraction of the ferrous-based feed wire in an exothermic reaction to generate substantial supplemental heat to the HVOF device. The molten/combusted metal is sprayed by the device onto the walls of the cylinder by the jet flow of gases.

Abstract: The cylinder walls of light metal engine blocks are thermally spray coated with a ferrous-based coating using an HVOF device. A ferrous-based wire is fed to the HVOF device to locate a tip end of the wire in a high temperature zone of the device. Jet flows of oxygen and gaseous fuel are fed to the high temperature zone and are combusted to generate heat to melt the tip end. The oxygen is oversupplied in relation to the gaseous fuel. The excess oxygen reacts with and burns a fraction of the ferrous-based feed wire in an exothermic reaction to generate substantial supplemental heat to the HVOF device. The molten/combusted metal is sprayed by the device onto the walls of the cylinder by the jet flow of gases.