The invention relates to a brake piston 1 for a brake caliper 9 of a disk brake, which is produced using working processes from a metallic material, in particular from a flat metal sheet, and is formed in one piece as a unilaterally open pot with a piston longitudinal axis A, with a piston wall 2 and with a piston head 3.

There is a need for robust and light as well as alternatively constructed, efficiently producible and well guided brake pistons.

The object is achieved firstly in principle on the basis of a cup-shapedly worked brake piston blank 19, in that at least one locally defined, i.e. partially cold-upset or partially ironed, cylindrical piston wall portion is present with a partially deformed piston wall 2 which is configured in adaptively modified manner by plastic material deformation by means of material redistribution (flow) including strain-hardening of its piston wall thickness of s1x.

Disclosed are novel bridged bi-aromatic phenol ligands and transition metal catalyst compounds derived therefrom. Also disclosed are methods of making the ligands and transition metal compounds, and polymerization processes utilizing the transition metal compounds for the production of olefin polymers.

Disclosed are novel bridged bi-aromatic phenol ligands and transition metal catalyst compounds derived therefrom. Also disclosed are methods of making the ligands and transition metal compounds, and polymerization processes utilizing the transition metal compounds for the production of olefin polymers.

A piston for an internal combustion engine is provided. The piston includes a lower part joined to an upper part, for example by friction welding with inertia. The upper part presents a combustion surface and an undercrown surface. The piston also includes a cooling gallery surface provided by the upper part and the lower part. The cooling gallery surface surrounds a volume of space for containing a cooling media. The piston can include serrations in the cooling gallery surface and/or undercrown surface to increase surface area and thus reduce the temperature of the piston. The piston can also include shaped weld curls, instead of or in addition to the serrations, which also increase surface area and reduce the temperature of the piston.

A one-piece piston including a combustion bowl which is cast to its final form and includes at least one irregularity spaced from a central axis. The piston is initially fabricated of an upper crown member and a lower crown member, which are joined together. The piston is then chucked into a machine tool, such as a CNC lathe, which locates either the piston's top surface or a portion of the combustion bowl and establishes its location as a datum plane. It is this datum plane which serves as a reference location for subsequent machining operations of the piston.

A one-piece piston including a combustion bowl which is cast to its final form and includes at least one irregularity spaced from a central axis. The piston is initially fabricated of an upper crown member and a lower crown member, which are joined together. The piston is then chucked into a machine tool, such as a CNC lathe, which locates either the piston's top surface or a portion of the combustion bowl and establishes its location as a datum plane. It is this datum plane which serves as a reference location for subsequent machining operations of the piston.

A piston and process for manufacturing a piston includes an upper part providing an upper combustion surface including a top land, a land ring and a combustion bowl. An undercrown surface is formed under the combustion bowl. A lower part including pin bosses and a piston skirt are formed under the undercrown surface. At least one of the upper part and the lower part are formed with metal injection molding.

A piston unit for coupling to a crosshead piston rod with a crosshead piston pin includes a piston crown member and an integrated crosshead pin support and skirt member. The piston crown member consists essentially of forged steel. An integrated crosshead pin support and skirt member consists essentially of forged steel. The integrated pin support and skirt member is affixed to the piston crown member and is configured to support the crosshead piston pin. In a method of making a crosshead piston, a piston crown member is forged from steel. An integrated crosshead pin support and skirt member is forged from steel. The piston crown member is welded to the integrated crosshead pin support and skirt member.

A method for producing a groove structure in an internal surface of a pin bore of a piston may include providing a rotatable boring bar with at least one cutting tool; advancing the boring bar while rotating at a first rotational speed in a direction of rotation with a first feed speed into the pin bore and introducing at least one helical first groove of the groove structure with a first depth and a first width into the internal surface; and retracting the boring bar, subsequent to introducing the at least one helical first groove, from the pin bore with a second feed speed while maintaining rotation at a second rotational speed in the direction of rotation; during the retracting of the boring bar at least one helical second groove is introduced into the internal surface.

A method for producing a groove structure in an internal surface of a pin bore of a piston may include providing a rotatable boring bar with at least one cutting tool; advancing the boring bar while rotating at a first rotational speed in a direction of rotation with a first feed speed into the pin bore and introducing at least one helical first groove of the groove structure with a first depth and a first width into the internal surface; and retracting the boring bar, subsequent to introducing the at least one helical first groove, from the pin bore with a second feed speed while maintaining rotation at a second rotational speed in the direction of rotation; during the retracting of the boring bar at least one helical second groove is introduced into the internal surface.