Abstract: The present invention reveals an improvement in an apparatus for injection molding a metallic material having dendritic properties. In the improvement, a sub-ring is placed under a piston ring on a sliding seal ring of a non-return valve assembly. The sub-ring seals the pressure and metal flow in the apparatus, virtually eliminates piston ring leakage and extends the usable life of the non-return valve assembly.

Abstract: In one embodiment, the invention comprises at least one and preferably a plurality, of rollers provided with recesses which are mounted on the drive and trailing assemblies of a conveyor system. The recesses of each roller include abutment surfaces angularly disposed relative to the central axes of their respective drive or trailing assemblies and are sized to receive, support and align the belt. Alternative embodiments employing polygonal rollers, rollers with a single wall forming two angled abutment surfaces and rollers with support surfaces disposed to receive multiple belt segments are also provided. The rollers, in addition, may include sets of the recesses distributed in circumferential rows about their periphery, including an odd number of sets of recesses to reduce wear on the roller. A method for estimating the optimum size and configuration of the rollers of the invention for helical woven wire endless belts is also provided.

Abstract: In one embodiment, the invention comprises at least one, and preferably a plurality, of rollers provided with recesses in their peripheral surfaces and mounted on the drive and trailing assemblies of a conveyor system. At least one side wall of each recess is angularly disposed relative to the central axes of the respective drive or trailing assemblies and the recesses are sized to receive therein a portion of the belt contacting the rollers. The bottom and side walls of the recesses act against the engaged portion of the belt to propel the belt through the system, support the belt and maintain the belt in proper tracking alignment. Alternative embodiments employing polygonal rollers, alternately slotted rollers and rollers with "single sided" recesses are also provided.

Abstract: In one embodiment, the invention comprises at least one roller with a plurality of recesses in its peripheral surface, mounted on the drive and trailing assemblies of a conveyor system. The recesses of each roller are angularly disposed relative to the central axes of their respective drive or trailing assemblies and are sized to receive a portion of an endless conveyor belt contacting the rollers. The bottom and size walls of the recesses act against the engaged portion of the belt to propel the belt through the system, support the belt and maintain the belt in proper tracking alignment. The recesses are preferably distributed in circumferential rows about the periphery of the roller and, in multi-row rollers, in a parallel relation across the width of the roller. A method for estimating the optimum size and configuration of the rollers of the invention for helical woven wire endless belts is also provided.

Abstract: A ferrous, sintered, powdered metal part is steam sealed and gas ferritic nitrocarburized to provide a part useful for high hardness applications without the brittleness normally associated with conventional hardening. The steam treating of the ferrous metal part seals off the interconnected porosity of the part with a coating of Fe.sub.2 O.sub.3, but not FeO, to limit the penetration of nitrocarburizing gases so that they produce a surface hardening without contributing to internal brittleness that results from the deeper penetration of the nitrogen treatment.