A method for producing a piston for an internal combustion engine may include the steps of: producing a piston upper part from a first blank via a deformation process; producing a piston lower part from a second blank via at least one of a deformation process and a casting process; connecting the first blank of the piston upper part and the second blank of the piston lower part to form a piston body via a welding process; and performing at least one of a secondary machining process and a finish machining process of the piston body to produce the piston.

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 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 method for producing a piston for internal combustion engines, where the piston includes a circumferential trapezoid annular groove for receiving trapezoid rings with small axial dimensions the groove having a groove base with adjoining surfaces and groove flanks. The groove base with adjoining surfaces is created in a first method step by machining using a cutting steel tool and the groove flanks are created in a further method step. Also disclosed are a piston produced according to the method and a cutting steel tool.

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 method for producing a piston for an internal combustion engine may include the steps of: producing a piston main body from a first blank via a deformation process; producing a piston ring part from a second blank via at least one of a deformation process and a casting process; pre-machining the first blank and the second blank, and finish machining a welding surface of the first blank and a welding surface of the second blank; connecting the pre-machined first blank and the pre-machined second blank via a welding process to form a piston body; and performing at least one of a secondary machining and a finish machining of the piston body to produce the piston.

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 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 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.