Abstract:
A repaired piston (610) includes a crown (616) composed of base (634) and welding filler materials (638), and having an annular rim (624) extending around a combustion bowl (622). A finite number of repaired defects (632) are within the annular rim (624), and have a spatial distribution limited by a multidirectional spacing parameter, and a size distribution limited by a unidirectional sizing parameter.
Abstract:
The invention relates to a method for producing a piston (10) for an internal combustion engine, comprising a piston main body (11) and a piston ring part (17), wherein the piston main body (11) has a combustion recess (12) having a dome (13), and comprising piston bosses (14) provided with boss bores (15), said piston bosses being connected to one another via running surfaces (16), wherein the piston ring part (17) comprises a piston floor (18), a circumferential fire land (19) and a circumferential ring part (21), and wherein the piston main body (11) and the piston ring part (17) form a circumferential cooling duct (22). According to the invention the method comprises the following steps: a) producing a blank (11') of the piston main body (11) by means of a forming method, b) producing a blank (17') of the piston ring part (17) by means of a forming method or a casting method, c) rough-machining the blanks (11', 17') and finish-machining welding faces (26, 26; 27, 29); d) connecting the rough-machined blanks (11", 111", 17") of piston main body (11) and piston ring part (17) by a welding method to form a piston body (30, 130), e) secondary machining and/or finish-machining the piston body (30, 130) to form a finished piston (10). According to the invention, in step a) during the production of the blank (11') of the piston main body (11), the contour of the combustion recess (12) away from a domed region (13a, 113a) is completed, surplus material (23, 123) is formed in the domed region (13a, 113a) of the combustion recess (12) and in step e) the surplus material (23, 123) in the domed region (13a, 113a) of the combustion recess (12) is removed in an amount such that a predetermined volume of the combustion recess (12) results.
Abstract:
A joined body formed by joining end surfaces of two joining members to each other by a friction welding, the joined body includes a hollow portion formed on at least one of the two joining members, the hollow portion being configured to have an opening at the joining face between the two joining members; and an annular groove portion formed on an inner circumferential surface of the hollow portion at a position separated from a joining face in an axial direction.
Abstract:
An exemplary system and method for welding a piston assembly includes a piston assembly having a cooling gallery and a loose granulated medium positioned therein. The cooling gallery is formed by a piston body and a cooling gallery ring, and a welder such as a laser welder is positioned proximate the assembly to weld the piston body to the cooling gallery ring. During welding, the assembly is rotated and the loose granulated medium is caused to remain in a gravitationally low portion of the cooling gallery. The weld is formed in an area proximate the loose granulated medium such that weld spatter emitted during welding is emitted into the loose granulated medium.
Abstract:
The invention relates to a drive unit (10) of a fluid-actuated linear drive (1) which is composed of a piston rod (12), a drive piston (15) sitting on the piston rod (12) and a buffer sleeve (24) likewise sitting on the drive piston (15). Said components (12, 15, 24) are fixed to one another by one and the same common weld joint (33). The invention further relates to a method for producing a drive unit (10) of this kind and also to a fluid-actuated linear drive (1) equipped with a drive unit (10) of this kind.
Abstract:
Die Erfindung betrifft ein Verfahren zur Herstellung eines Gaswechselventils (1')für eine Hubkolbenbrennkraftmaschine, insbesondere Auslassventil für einen längsgespülten Zweitakt-Grossdieselmotor, bei welchem Verfahren ein Ventilkörper bereitgestellt wird, umfassend einen sich entlang einer axialen Ventilschaftachse (A') erstreckenden Ventilschaft (2'), sowie einen sich an den Ventilschaft anschliessenden Ventilteller (3'), der sich in axialer Richtung vom Ventilschaft weg, und in Bezug auf die Ventilschaftachse (A') radial erweiternd nach aussen erstreckt. Dabei ist zwischen einer im wesentlichen orthogonal zur Ventilschaftachse (A') ausgebildeten Fussfläche (31') des Ventiltellers und dem Ventilschaft, eine Ventilsitzfläche (32') am Ventilteller (3') ausgebildet, wobei auf einem vorgebbaren Bereich der Fussfläche des Ventiltellers eine Korrosionsschutzbeschichtung (5', 51', 52') vorgesehen wird. Erfindungsgemäss wird die Korrosionsschutzbeschichtung mittels eines Metall-Schutzgasschweissverfahrens aufgeschweisst. Des weiteren betrifft die Erfindung ein nach dem erfindungsgemässen Verfahren hergestelltes Gaswechselventil.
Abstract:
A surface hardening material being excellent in impact resistance and having abrasion resistance is provided. Provided are: a high-toughness cobalt-based alloy containing 25.0 to 40.0 mass% of Cr, 0.5 to 12.0 mass% of a sum of W and/or Mo, 0.8 to 5.5 mass% of Si, and 0.5 to 2.5 mass% of B, 8.0 mass% or less of each of Fe, Ni, Mn, and Cu, and 0.3 mass% or less of C, the sum amount of Fe, Ni, Mn, Cu, and C being 10.0 mass% or less, and the remainder comprising 48.0 to 68.0 mass% of Co and unavoidable impurities; and an engine valve coated with the same.