Abstract: Provided is a TRIP-aided dual-phase martensitic steel which is excellent in terms of strength-elongation balance and Charpy impact value and has dual-phase martensite composed of a soft lath martensitic structure and a hard lath martensitic structure as a matrix phase, regardless of forging temperature or forging reduction ratio, by controlling heat treatment conditions. The dual-phase martensitic steel contains 0.1-0.7% C, 0.5-2.5% Si, 0.5-3.0% Mn, 0.5-2.0% Cr, 0.5% or less (including 0%) of Mo, 0.04-2.5% Al, and the balance Fe with incidental impurities; has its metallographic structure in which a matrix phase is composed of a soft lath martensitic structure and a hard lath martensitic structure; and obtained by heating its raw steel material to a ?-range, rapidly cooling the heated material to a temperature slightly above a martensite transformation starting temperature (Ms), and then performing an isothermal transformation process the cooled material in the temperature range from Mf to [(Mf)?100° C].

Abstract: A high-strength steel machined product giving excellent hardenability has a metal microstructure with excellent balance of strength and toughness and high stability of retained austenite. The product is composed of an ultra-high low-alloy TRIP steel having a metal microstructure which contains an appropriate quantity of two or more of Cr, Mo, and Ni, and an appropriate quantity of one or more of Nb, Ti, and V, and having an appropriate value of carbon equivalent; the metal microstructure has a mother-phase structure composed mainly of lathy bainitic ferrite with a small amount of granular bainitic ferrite and polygonal ferrite, and has a secondary-phase structure composed of fine retained austenite and martensite.

Abstract: A high-strength steel machined product giving excellent hardenability has a metal microstructure with excellent balance of strength and toughness and high stability of retained austenite. The product is composed of an ultra-high low-alloy TRIP steel having a metal microstructure which contains an appropriate quantity of two or more of Cr, Mo, and Ni, and an appropriate quantity of one or more of Nb, Ti, and V, and having an appropriate value of carbon equivalent; the metal microstructure has a mother-phase structure composed mainly of lathy bainitic ferrite with a small amount of granular bainitic ferrite and polygonal ferrite, and has a secondary-phase structure composed of fine retained austenite and martensite.

Abstract: A common-rail injection system is provided for a diesel engine and has excellent internal pressure fatigue resisting characteristics, vibrational fatigue resisting characteristics and cavitation resisting property and sheet face flawing resisting property, and can be made thin and light in weight. A main pipe rail is manufactured by transformation induced plastic type strength steel. After the main pipe rail is processed, residual austenite is generated by heat treatment, and the reduction processing of stress concentration of a branch hole and a main pipe rail side flow passage crossing portion is performed. Further, it is preferable that an induced plastic transformation is generated on the inner surface of the main pipe rail by autofrettage processing, and compression residual stress is left.

Abstract: A common-rail injection system is provided for a diesel engine and has excellent internal pressure fatigue resisting characteristics, vibrational fatigue resisting characteristics and cavitation resisting property and sheet face flawing resisting property, and can be made thin and light in weight. A main pipe rail is manufactured by transformation induced plastic type strength steel. After the main pipe rail is processed, residual austenite is generated by heat treatment, and the reduction processing of stress concentration of a branch hole and a main pipe rail side flow passage crossing portion is performed. Further, it is preferable that an induced plastic transformation is generated on the inner surface of the main pipe rail by autofrettage processing, and compression residual stress is left.

Abstract: A common-rail injection system is provided for a diesel engine and has excellent internal pressure fatigue resisting characteristics, vibrational fatigue resisting characteristics and cavitation resisting property and sheet face flawing resisting property, and can be made thin and light in weight. A main pipe rail is manufactured by transformation induced plastic type strength steel. After the main pipe rail is processed, residual austenite is generated by heat treatment, and the reduction processing of stress concentration of a branch hole and a main pipe rail side flow passage crossing portion is performed. Further, it is preferable that an induced plastic transformation is generated on the inner surface of the main pipe rail by autofrettage processing, and compression residual stress is left.

Abstract: In a high pressure fuel injection pipe, pipe extension and heat treatment are repeated by using a header manufactured by transformation induced plastic type strength steel. A process for depositing residual austenite is then performed, after which a final pipe extension process is performed, and the joint portion is molded and bending processing is performed without performing perfect annealing at the size of a product.

Abstract: There is provided a high-pressure fuel pipe for diesel engines, which is excellent in inner-pressure fatigue resistant property, vibrational fatigue resistant property, cavitation-resistant property, seat surface crack resistant property, and bending shape stability, and capable of thinning and lightening. A high-pressure fuel pipe for diesel engines, composed of a low alloy transformation inducing plastic type strength steel containing residual austenite of 5 to 40 wt %, and wherein an inner surface of a flow passage has a crack depth of 20 ?m or less, and plastic working is applied to an inner surface of a flow passage.

Abstract: A high pressure fuel injection pipe is provided for a diesel engine and has excellent internal pressure fatigue resisting characteristics, vibrational fatigue resisting characteristics and cavitation resisting property and sheet face flawing resisting property, and can be made thin and light in weight. In the high pressure fuel injection pipe, pipe extension and heat treatment are repeated by using a header manufactured by transformation induced plastic type strength steel, and processing for depositing residual austenite is then performed and final pipe extension processing is performed, and a joint portion is molded and bending processing is performed without performing perfect annealing at the size of a product.

Abstract: A common-rail injection system is provided for a diesel engine and has excellent internal pressure fatigue resisting characteristics, vibrational fatigue resisting characteristics and cavitation resisting property and sheet face flawing resisting property, and can be made thin and light in weight. A main pipe rail is manufactured by transformation induced plastic type strength steel. After the main pipe rail is processed, residual austenite is generated by heat treatment, and the reduction processing of stress concentration of a branch hole and a main pipe rail side flow passage crossing portion is performed. Further, it is preferable that an induced plastic transformation is generated on the inner surface of the main pipe rail by autofrettage processing, and compression residual stress is left.

Abstract: An oil-through type push rod for, for instance, internal combustion engines including a metal pipe and a metal end fitting which has an oil hole formed therein and is welded to the end of the metal pipe, the metal pipe being provided with a covering layer of a low-melting-point metal for fixing a welding spatter generated during welding, and such a low-melting-point metal covering layer being disposed on at least an inside wall surface of the metal pipe so as to be near an area where the metal end fitting is welded.

Abstract: An oil-through type push rod for, for instance, internal combustion engines including a metal pipe and a metal end fitting which has an oil hole formed therein and is welded to the end of the metal pipe, the metal pipe being provided with a covering layer of a low-melting-point metal for fixing a welding spatter generated during welding, and such a low-melting-point metal covering layer being disposed on at least an inside wall surface of the metal pipe so as to be near an area where the metal end fitting is welded

Abstract: A fuel delivery rail assembly for supplying fuel to a plurality of fuel injectors in an engine is provided. The assembly comprises an elongate conduit having a longitudinal fuel passage therein, a fuel inlet pipe, and a plurality of sockets. Outer walls of the conduit include at least one flat or arcuate flexible first absorbing surface, which is smoothly and integrally connected to an arcuate second absorbing surface. The first absorbing surface or the second absorbing surface faces fuel inlet ports of the sockets. The sectional configuration of the conduit can be flat, a telephone receiver shape, a character “T” shape, a corrugation shape, a dumbbell shape or a reverse eye mask shape. Thus, fuel pressure pulsations and shock waves are reduced by abrupt enlargements of fuel passages and bendings of the absorbing surfaces.

Abstract: A heat and corrosion resistant steel pipe having multi-layered coating comprising a steel pipe, a Zn—Ni alloy plating layer deposited to the outer surface of the steel pipe and a polyvinyl fluoride layer formed on the Zn—Ni alloy plating layer with an epoxy resin therebetween as an intermediate layer. A metal plating layer comprising Zn—Ni plating layer and Ni-plating layer may be used instead of the Zn—Ni plating layer. A chromate layer may be formed on the metal plating layer.

Abstract: A fuel delivery rail assembly for supplying fuel to a plurality of fuel injectors in an engine is provided. The assembly comprises an elongate conduit having a longitudinal fuel passage therein, a fuel inlet pipe, and a plurality of sockets. Outer walls of the conduit include at least one flat or arcuate flexible first absorbing surface, which is smoothly and integrally connected to an arcuate second absorbing surface. The first absorbing surface or the second absorbing surface faces fuel inlet ports of the sockets. The sectional configuration of the conduit can be flat, a telephone receiver shape, a character “T” shape, a corrugation shape, a dumbbell shape or a reverse eye mask shape. Thus, fuel pressure pulsations and shock waves are reduced by abrupt enlargements of fuel passages and bendings of the absorbing surfaces.

Abstract: A flared connection structure of a pipe end portion is provided. The structure includes a bridge flare with a spool portion with a U-shape or V-shape section that bulges outwardly to define front and rear inclined faces. A ring member with a U-shape cross-section has a rear portion disposed in the pocket between the front and rear inclined faces of the spool portion. The ring member also has a front face disposed between the front inclined face of the spool portion and the pressure receiving seat face of a counterpart joint. A pattern of concentric circles formed by recesses and projections is provided on at least one of the faces of the front portion of the ring member or the pressure receiving seat face of the counterpart joint.

Abstract: A fuel delivery rail assembly for supplying fuel to a plurality of fuel injectors in an engine is provided. The assembly comprises an elongate conduit having a longitudinal fuel passage therein, a fuel inlet pipe, and a plurality of sockets. Outer walls of the conduit include at least one flat or arcuate flexible first absorbing surface, which is smoothly and integrally connected to an arcuate second absorbing surface. The first absorbing surface or the second absorbing surface faces fuel inlet ports of the sockets. The sectional configuration of the conduit can be flat, a telephone receiver shape, a character “T” shape, a corrugation shape, a dumbbell shape or a reverse eye mask shape. Thus, fuel pressure pulsations and shock waves are reduced by abrupt enlargements of fuel passages and bendings of the absorbing surfaces.

Abstract: A heat and corrosion resistant steel pipe having multi-layered coating comprising a steel pipe, a Zn—Ni alloy plating layer deposited to the outer surface of the steel pipe and a polyvinyl fluoride layer formed on the Zn—Ni alloy plating layer with an epoxy resin being intervened therebetween as an intermediate layer. A metal plating layer comprising Zn—Ni plating layer and Ni-plating layer may be used instead of the Zn—Ni plating layer. A chromate layer may be formed on the metal plating layer.

Abstract: An apparatus is provided for manufacturing a high quality multi-wound metal tube having satisfactory adhesion between multi-wound walls and for a seam portion at a reduced cost. Walls of the multi-wound tubular body are pressure welded with each other and then cooled, while at least the outer circumference of a brazing material between the walls of the multi-wound tubular body is kept at a flowable temperature by heating, by using at least one of a step of pressing substantially uniformly the outer circumferential surface of the tubular body in a radial direction from the outside, a step of substantially uniformly pressing the inner circumferential surface of the tubular body in the radial direction from the inside or a step of exerting a tensile force to the tubular body in the direction of the tubular axis.

Abstract: A multi-layered metallic pipe having resistances to the chipping of pebbles and splashing of muddy water while driving a vehicle and excellent corrosion resistances. The multi-layered metallic pipe is piped without scraping and does not need an insulator. The multi-layered metallic pipe includes a metallic pipe having a relatively small plated diameter with a film made of zinc, aluminum or a zinc/aluminum based alloy on the outer circumference of the metallic pipe. A first layer of a polyamide resin, a polyviny fluoride, or a polyvinylidene fluoride having a film thickness of 20 to 50 microns is applied to the plated film. A second layer made of an extrudible resin having a film thickness of 100 microns to 1.0 millimeter and a chipping resistance is coated over the first layer along an entire length of the first layer. The second layer is formed to have stepped portions of different thickness.