Abstract: An internal combustion engine may include at least one cylinder and at least one hollow-heat valve. The at least one hollow-head valve may include a valve shaft and a valve head, and may be guided in a valve shaft guide. The engine may also include at least one valve seat ring on which the valve head sealingly lies when the at least one hollow-head valve is closed. The engine may additionally include a valve shaft seal with at least two seal lips and oil disposed between the valve shaft and the valve shaft guide. The at least one valve seat ring may be composed of a sintered metal including infiltrated copper. The valve shaft may include one of a chromium-containing coating and a boron carbide-containing coating.

Abstract: A method for producing at least one hollow valve for gas exchange may include introducing a bore into a valve shaft and into a valve head to form the at least one hollow valve, measuring a depth of the bore, washing the at least one hollow valve at least once, providing the at least one hollow valve in a retaining device, orienting the retaining device together with the at least one hollow valve with respect to an associated electrode, moving the associated electrode in relation to the at least one hollow valve, inserting the associated electrode into the bore of the at least one hollow valve, enlarging the bore in a region of the valve head by electromechanical machining processes, removing the associated electrode from the at least one hollow valve, rinsing and/or preserving the at least one hollow valve, and measuring a wall thickness of a valve bottom.

Abstract: A gas exchange valve for an internal combustion engine may include a valve stem and a wear resistance improving functional layer. The valve stem may extend in an axial direction and may transition into a valve plate in the axial direction. The functional layer may include nickel and tungsten. The functional layer may be arranged in a coating area on an outer circumference of the valve stem and may at least partially define a sliding surface.

Abstract: A gas exchange valve for an internal combustion engine may include a valve stem and a wear resistance improving functional layer. The valve stem may extend in an axial direction and may transition into a valve plate in the axial direction. The functional layer may include nickel and tungsten. The functional layer may be arranged in a coating area on an outer circumference of the valve stem and may at least partially define a sliding surface.

Abstract: An internal combustion engine may include at least one cylinder and at least one hollow-heat valve. The at least one hollow-head valve may include a valve shaft and a valve head, and may be guided in a valve shaft guide. The engine may also include at least one valve seat ring on which the valve head sealingly lies when the at least one hollow-head valve is closed. The engine may additionally include a valve shaft seal with at least two seal lips and oil disposed between the valve shaft and the valve shaft guide. The at least one valve seat ring may be composed of a sintered metal including infiltrated copper. The valve shaft may include one of a chromium-containing coating and a boron carbide-containing coating.

Abstract: A gas exchange valve for an internal combustion engine has a valve body including a valve stem extending along an axial valve stem axis and a valve head adjoining the valve stem radially widening with regarding to the valve stem axis and extending in an axial direction away from the valve stem along the axial valve stem axis. Between a base surface of the valve head formed substantially orthogonally to the valve stem axis and the valve stem, a valve seat surface is formed on the valve head. In the base surface of the valve head, at least one recess is provided, wherein the at least one recess is arranged to locally reduce a stiffness of the valve head in a region of the valve seat surface.

Abstract: A method for manufacturing a valve may include welding two components to each other via a combined induction/friction welding process. One of the two components may be a valve head and the other of the two components may be a valve stem.

Abstract: A method for measuring a wall thickness in hollow valves may include determining a wall thickness in a region of a valve stem using at least one ultrasonic sensor, wherein the one ultrasonic sensor may be oriented with respect to a surface on the valve stem in such a manner that an emitted ultrasound may be introduced into the surface in a perpendicular manner. The method may additionally or alternatively include determining a wall thickness in a region of a chamfer using the at least one ultrasonic sensor, wherein the at least one ultrasonic sensor may be positioned at a location on the chamfer at which an inner tangent in a cavity runs parallel to an outer tangent on the chamfer, and wherein the ultrasonic sensor is oriented with respect to the tangents in such a manner that an emitted ultrasound is introduced into the surface in a perpendicular manner.

Abstract: A method for producing at least one hollow valve for gas exchange may include introducing a bore into a valve shaft and into a valve head to form the at least one hollow valve, measuring a depth of the bore, washing the at least one hollow valve at least once, providing the at least one hollow valve in a retaining device, orienting the retaining device together with the at least one hollow valve with respect to an associated electrode, moving the associated electrode in relation to the at least one hollow valve, inserting the associated electrode into the bore of the at least one hollow valve, enlarging the bore in a region of the valve head by electromechanical machining processes, removing the associated electrode from the at least one hollow valve, rinsing and/or preserving the at least one hollow valve, and measuring a wall thickness of a valve bottom.

Abstract: A device for producing at least one hollow valve for a gas exchange system may include at least one valve holder. The at least one valve holder may include a valve stem centring element, a valve receptacle and a valve head holder. The valve receptacle may receive a valve stem and the valve head holder may receive a valve head. A first carrier and a second carrier may be provided. The valve holder may be arranged on the first carrier. At least one cathode holder may be arranged on the second carrier. The cathode holder may include a cathode that is insertable through the first carrier via the valve stem centring element. At least one contact plate may be arranged opposite the valve head holder.

Abstract: A piston for an internal combustion engine may include a surface in a region on a crankshaft side. The piston may include a thermally conductive coating disposed on the surface via thermal spraying.

Abstract: A metallic hollow valve for an internal combustion engine of a utility vehicle may include a tubular valve stem and a valve head merging into the valve stem. The valve head may have an outer diameter that is enlarged compared to the valve stem. The valve stem and the valve head may together delimit a hollow space. The valve stem may have an outer diameter of more than 7 mm, for example between 8 mm and 11 mm. The valve stem may have an inner diameter of at least 4.5 mm, for example between 5 mm and 7 mm.

Abstract: A gas exchange valve of an internal combustion engine may include a hollow valve stem and a valve disc. The valve disc may include a valve bottom and a hollow valve cone which is connected to an outer edge of said valve bottom. The hollow valve cone may taper with increasing distance from the valve bottom. The valve stem may pass through the hollow valve cone. The valve stem may be fixedly connected on the one hand to the valve bottom and on the other hand to the tapered end of the valve cone. The valve stem may include a first hollow space which is fluidically separated from a second hollow space arranged in the valve disc. The first hollow space and the second hollow space may have a different cooling agent filling level.

Abstract: A method for measuring a wall thickness in hollow valves may include determining a wall thickness in a region of a valve stem using at least one ultrasonic sensor, wherein the one ultrasonic sensor may be oriented with respect to a surface on the valve stem in such a manner that an emitted ultrasound may be introduced into the surface in a perpendicular manner. The method may additionally or alternatively include determining a wall thickness in a region of a chamfer using the at least one ultrasonic sensor, wherein the at least one ultrasonic sensor may be positioned at a location on the chamfer at which an inner tangent in a cavity runs parallel to an outer tangent on the chamfer, and wherein the ultrasonic sensor is oriented with respect to the tangents in such a manner that an emitted ultrasound is introduced into the surface in a perpendicular manner.

Abstract: A method for producing a hollow valve of an internal combustion engine may include providing a hollow valve stem, a valve cone, and a valve bottom; pushing the valve cone over the valve stem via a press fit, wherein the valve cone includes an outer surface transitioning to the valve stem to define a testing surface; and welding the valve cone to the valve stem via at least one of a laser beam and an electron beam, wherein the welding occurs such that no melting of the outer surface in the region of the testing surface of the valve cone occurs.

Abstract: A device for producing at least one hollow valve for a gas exchange system may include at least one valve holder. The at least one valve holder may include a valve stem centring element, a valve receptacle and a valve head holder. The valve receptacle may receive a valve stem and the valve head holder may receive a valve head. A first carrier and a second carrier may be provided. The valve holder may be arranged on the first carrier. At least one cathode holder may be arranged on the second carrier. The cathode holder may include a cathode that is insertable through the first carrier via the valve stem centring element. At least one contact plate may be arranged opposite the valve head holder.

Abstract: A metallic hollow valve may include a tubular shaft having a cavity. The shaft may be coupled to a valve head. The shaft may have an external diameter of 5.0 mm<da<6.0 mm and an internal diameter of 3.0 mm<di<4.6 mm. The hollow valve may include a cavity disposed in the valve head. A wall surrounding the cavity in the valve head may include a thickness of 1.0 mm<b1,2<2.0 mm.

Abstract: A gas exchange valve of an internal combustion engine may include a hollow valve stem and a valve disc. The valve disc may include a valve bottom and a hollow valve cone which is connected to an outer edge of said valve bottom. The hollow valve cone may taper with increasing distance from the valve bottom. The valve stem may pass through the hollow valve cone. The valve stem may be fixedly connected on the one hand to the valve bottom and on the other hand to the tapered end of the valve cone. The valve stem may include a first hollow space which is fluidically separated from a second hollow space arranged in the valve disc. The first hollow space and the second hollow space may have a different cooling agent filling level.

Abstract: A method for producing a hollow valve of an internal combustion engine may include providing a hollow valve stem, a valve cone, and a valve bottom; pushing the valve cone over the valve stem via a press fit, wherein the valve cone includes an outer surface transitioning to the valve stem to define a testing surface; and welding the valve cone to the valve stem via at least one of a laser beam and an electron beam, wherein the welding occurs such that no melting of the outer surface in the region of the testing surface of the valve cone occurs.

Abstract: A method for producing a hollow valve of an internal combustion engine may include providing a valve stem and a valve disc having a valve bottom and a valve cone; placing the valve bottom centrally in a mounting of an assembly device; holding the valve stem via a holding device; concentrically placing the valve stem onto the valve bottom and rotating the valve stem together with the valve bottom; welding the valve stem to the valve bottom; pushing the valve cone over the valve stem until the valve stem contacts the valve bottom; welding the valve cone together with the valve bottom; and welding the valve cone together with the valve stem.