A cooling channel piston for an internal combustion engine which includes a piston bottom and a piston shaft that are joined thereto of a friction welding process. The piston bottom and the piston shaft jointly form a cooling channel. An annular wall which radially delimits the cooling channel towards the outside is formed by the piston bottom and/or the piston shaft. The annular wall can be sealed by a welding process once the piston bottom and the piston shaft have been joined together.

Disclosed is a monoblock or cooling channel piston and a method for producing a monoblock piston for use in an internal combustion engine. A piston blank includes a circumferential collar protruding radially in the region of the piston crown is first produced and the collar is then shaped. A contact region on a top region of the piston skirts and the collar is shaped such that the outer circumferential edge thereof points at a distance to the contact region and forms a defined gap. The gap is then sealed by a closure element in order to form a closed cooling channel.

A piston includes an upper member having a crown and a combustion surface extending radially inward from the crown. The upper member includes concentrically oriented first and second upper connecting surfaces integrally formed on the bottom side of the upper member. At least one of the upper connecting surfaces includes a curvilinear and/or multi-arcuate cross-sectional profile. The piston also includes a lower member having a pair of opposing skirts, each skirt defining a bore. The lower member also includes concentrically oriented first and second lower connecting surfaces integrally formed on a top side of the lower member. The lower member is integrally connected to the upper member by friction welding. The curvilinear and/or multi-arcuate profile enables a shortened distance between the top surface of the crown and the bore centerline of the bore. Methods of manufacturing the piston are also disclosed.

A monobloc piston body for an internal combustion engine is provided. The piston body includes a first piece which includes a pair of skirt portions and a pair of pin bosses and a second piece which includes a crown portion with an upper combustion surface and an at least partially enclosed oil gallery. The first and second pieces are joined together at a joint that is located on a side of the oil gallery opposite of the upper combustion surface. The first piece is made through casting or forging, and the second piece is made through an additive manufacturing process, such as direct metal laser sintering.

A piston and method of construction thereof are provided. The piston includes an upper crown having an upper combustion surface and a lower crown depending therefrom. The lower crown includes a pair of laterally spaced, axially aligned pin bores configured for receipt of a wrist pin. A substantially closed, annular outer cooling gallery is formed between the upper and lower crowns, wherein a bottom surface of the cooling gallery is formed by a floor of the lower crown. An oil inlet and an oil outlet extend through the floor. The oil inlet includes an upstanding toroid-shaped protrusion that extends upwardly from the floor into the cooling gallery, wherein the protrusion is formed as a monolithic extrusion from the material of the lower crown floor.

A piston including a piston crown, the piston crown defining a combustion bowl with a bowl base and bottom surface. A failure initiation structure is provided on the bottom surface of the combustion bowl to initiate favorable fracture at predetermined loads. Such favorable fracture may lead to the a separation of a fragment of the bowl base from the combustion bowl when a predetermined load or pressure is exceeded within the combustion bowl.

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 of making an engine system component is disclosed. The method may include loading a first metal-based material and a second metal-based material into an extrusion chamber. The first metal-based material may concentrically surround the second metal-based material, and the first metal-based material may have at least one of a thermal property and a wear resistance different than the second metal-based material. The method may additionally include forming an extrudate by simultaneously passing the first metal-based material and the second metal-based material through a die. The first metal-based material of the extrudate may be metallurgically bonded to the second metal-based material of the extrudate. The method may also include forging the extrudate.

A piston, (1) incorporates a pair of tear-drop shaped springs (6) acting, in use, between the crown (2) of the piston and an associated connecting rod (4) so as to bias the connecting rod away from the piston crown (2). The springs (6) are supported by support members (7 and 8), the springs being located substantially in the region of the piston crown (2). A carrier (5) is positioned within the piston (1), the carrier being slidably mounted within the piston for axial movement relative thereto, and being connected to the connecting rod (4) in such a manner that the springs (6) permit the carrier (5) to move axially relative to the piston crown (2). The springs (6) are made of a beta titanium alloy such as gum metal.

A steel piston with an oil gallery, and process for forming a steel piston oil gallery channel, which corresponds to the complex shape of the combustion bowl in the piston crown. The oil gallery channel is first forged to the basic shape that corresponds to the shape of the walls of the combustion bowl. Machine-turning surfaces in the oil gallery channel can be machine-finished as desired. Surfaces in the oil gallery which cannot be machined with conventional turning operations, such as recesses and protrusions into the channel, are left in the original forged condition.