Abstract: A method for producing a cavity valve is provided. The method includes providing a valve body which has a cavity in the interior. The valve body has a circular opening having an opening edge surface on a bottom side. A circular valve cover with a cover edge surface is provided. Inductive heating of at least one of the opening edge surface or the cover edge surface takes place and then welding the valve body to the valve cover by friction welding of the opening edge surface to the cover edge surface.

Abstract: A matrix for shaping a valve preform has a circular through opening and a reduced conical section. The reduced conical section tapers from an outer diameter to a reduced cone inner diameter, the outer diameter being greater than or equal to the initial outer diameter of the valve preform, and the matrix inner diameter being smaller than the initial outer diameter.

Abstract: A method for producing a valve body of a hollow valve includes providing a workpiece blank or semi-finished product, spin extruding the workpiece to produce a preform having a cup with a hollow shape formed by the cup wall. A hollow valve produced by this method is also provided.

Abstract: A cover body (2) for a valve rotating device includes a ring-shaped upper part (4) and a ring-shaped lower part (6). The upper part (4) and the lower part (6) are axially spaced apart and are adapted to accommodate an axial spring element (24) therebetween. The upper part (4) and the lower part (6) are connected to one another by at least one connecting piece arranged at the location opposite an insertion position of the axial spring element (24). A valve rotating device (12) having such a cover body is also provided. A ring-shaped base body (22) has a plurality of pockets (16) oriented in a circumferential direction, in each of which a ball (14) and a tangential spring (32) are arranged. The pockets (16) have a variable depth in the circumferential direction such that inclined raceways (26) for the balls (14) arranged therein are formed. The tangential springs (32) push the balls (14) toward an end of the respective pocket (16).

Abstract: A method for producing a valve body of a hollow valve with optimised interior stem geometry includes a preform with a valve plate and a tubular wall surrounding a cavity. Flow forming the tubular wall over a flow-forming mandrel, which is inserted into the cavity to enlarge a length of the tubular wall. An interior area of the tubular wall is embossed with a structure either due to the fact that the flow-forming mandrel is a structuring mandrel having a surface structure, or alternatively, because the method includes a further step of reducing an outer diameter of the tubular wall by swaging or drawing and ironing over a structuring mandrel. Furthermore, a hollow valve is produced by this method.

Abstract: A production method for a valve body of a hollow valve includes providing a preform with a valve head and a tubular wall which surrounds a cylindrical cavity. The tubular wall is flow formed above a flow forming mandrel which is inserted into the cavity in order to increase a length of the tubular wall. A hollow valve produced by flow forming is also disclosed.

Abstract: The invention relates to a method for producing a valve body for a hollow valve. Said method comprises the following steps: providing a workpiece, blank or semi-finished product and a forming punch, introducing a protective layer between the workpiece and the forming punch (22) and press forming the workpiece to produce a preform. The invention also relates to a hollow valve produced by means of this method.

Abstract: A method for producing a valve body of a hollow valve includes providing a workpiece blank or semi-finished product, spin extruding the workpiece to produce a preform having a cup with a hollow shape formed by the cup wall. A hollow valve produced by this method is also provided.

Abstract: The invention relates to a method for producing a valve body for a hollow valve. Said method comprises the following steps: providing a workpiece, blank or semi-finished product and a forming punch, introducing a protective layer between the workpiece and the forming punch (22) and press forming the workpiece to produce a preform. The invention also relates to a hollow valve produced by means of this method.

Abstract: An internally cooled valve (2) includes a valve body having a valve head (4) and a valve stem (6). The valve body has at least one cavity (8) in which coolant (10) is situated. The coolant is a nanofluid (12) in which nanoparticles (14) are dispersed in a dispersion medium (16).

Abstract: A method for manufacturing an internally cooled valve (2), includes providing a valve body (4) having a valve stem (6) that ends in a valve head (8). The valve body (4) has a cavity (10) that is open toward the valve head (8) and with a valve base element (12) by friction welding the valve base element (12) to the valve head (8). The valve bottom element (12) is preferably a sintered component.

Abstract: A hollow valve having optimized interior stem geometry, whose valve stem has surface-enlarging structuring on an inner surface is provided. Also provided is a method for manufacturing a valve body of such a hollow valve, wherein the method comprises: providing a bowl-shaped semi-finished product having an annular wall that surrounds a cavity, and having a base section, followed by lengthening the wall with an inserted, structured mandrel, and lastly, reducing an outer diameter of the annular wall without a mandrel to obtain a predetermined valve stem outer diameter of a valve to be manufactured.

Abstract: A method for manufacturing a poppet valve or mushroom valve includes providing a mixture of metal powder and a binder, filling and pressing said mixture in a mold, to obtain a green product, removing the binder from the green product, and thermally sintering the green product to a poppet valve blank, by hot isostatic pressing. A poppet valve is also provided that is manufactured with this method.

Abstract: A valve rotating device has an annular main body, an annular cover body, and an annular axial spring element. The main body has multiple pockets of variable depth so that raceways are formed for balls situated therein, wherein tangential springs press the balls against ends of the pockets in the circumferential direction. The cover body is rotatable relative to the main body about an axis and is axially displaceable, and has an annular first support element, an annular second support element, and a connection, wherein the support elements are axially spaced apart from one another and the connection connects the support elements so that they are fixed relative to one another. The axial spring element at a first end rests on an annular stop surface of the main body, and at a second end rests on a surface of the first support element, wherein the axial spring element is situated between the first support element and the second support element.

Abstract: Disclosed is a method for the production of a valve body of a hollow chamber valve, said method comprising: providing a bowl-shaped semi-finished product having an annular wall, which surrounds a hollow chamber, and a bottom portion, followed by a lengthening of the wall and a final reducing of an outer diameter of the annular wall in order to obtain a predetermined valve shaft outside diameter of a valve that is to be produced. Further disclosed is a hollow chamber valve produced by means of said method.

Abstract: A method for producing a cavity valve is provided. The method includes providing a valve body which has a cavity in the interior. The valve body has a circular opening having an opening edge surface on a bottom side. A circular valve cover with a cover edge surface is provided. Inductive heating of at least one of the opening edge surface or the cover edge surface takes place and then welding the valve body to the valve cover by friction welding of the opening edge surface to the cover edge surface.

Abstract: A production method for a valve body of a hollow valve includes providing a preform with a valve head and a tubular wall which surrounds a cylindrical cavity. The tubular wall is flow formed above a flow forming mandrel which is inserted into the cavity in order to increase a length of the tubular wall. A hollow valve produced by flow forming is also disclosed.

Abstract: A cover body (2) for a valve rotating device includes a ring-shaped upper part (4) and a ring-shaped lower part (6). The upper part (4) and the lower part (6) are axially spaced apart and are adapted to accommodate an axial spring element (24) therebetween. The upper part (4) and the lower part (6) are connected to one another by at least one connecting piece arranged at the location opposite an insertion position of the axial spring element (24). A valve rotating device (12) having such a cover body is also provided. A ring-shaped base body (22) hasg a plurality of pockets (16) oriented in a circumferential direction, in each of which a ball (14) and a tangential spring (32) are arranged. The pockets (16) have a variable depth in the circumferential direction such that inclined raceways (26) for the balls (14) arranged therein are formed. The tangential springs (32) push the balls (14) toward an end of the respective pocket (16).

Abstract: The invention relates to a method for producing poppet valves, the method including: cross-wedge rolling a preform (2), which has at least one disk portion (4) and a shaft portion, to produce a valve blank (10), wherein a diameter of the shaft portion (6) is reduced substantially to a shaft diameter of a shaft (16), and additionally a length of the shaft portion (6) is increased substantially to a length of the shaft (16) by means of a rolling-out process.

Abstract: A method for producing a valve body of a hollow valve with optimised interior stem geometry includes a preform with a valve plate and a tubular wall surrounding a cavity. Flow forming the tubular wall over a flow-forming mandrel, which is inserted into the cavity to enlarge a length of the tubular wall. An interior area of the tubular wall is embossed with a structure either due to the fact that the flow-forming mandrel is a structuring mandrel having a surface structure, or alternatively, because the method includes a further step of reducing an outer diameter of the tubular wall by swaging or drawing and ironing over a structuring mandrel. Furthermore, a hollow valve is produced by this method.