Abstract: A pre-finished piston part is disclosed that may be used to form a piston assembly. A pre-finished piston may include a lower part defining a piston axis, the lower part having a skirt and forming a lower surface of a cooling gallery. The lower part may include a radially inner bowl surface defining a lower part radially inner mating surface. The pre-finished piston assembly may further include an upper part having a radially outer bowl surface meeting the radially inner bowl surface at a radially inner joint. The upper part may include a radially inner wall defining a radially inner upper part mating surface. The radially inner wall may define a radially inwardly facing surface that defines a non-parallel angle with the radially inner bowl surface where the radially inner bowl surface meets the radially innermost edge of the radially inner mating surface.

Abstract: A pre-finished piston part is disclosed that may be used to form a piston assembly. A pre-finished piston may include a lower part defining a piston axis, the lower part having a skirt and forming a lower surface of a cooling gallery. The lower part may include a radially inner bowl surface defining a lower part radially inner mating surface. The pre-finished piston assembly may further include an upper part having a radially outer bowl surface meeting the radially inner bowl surface at a radially inner joint. The upper part may include a radially inner wall defining a radially inner upper part mating surface. The radially inner wall may define a radially inwardly facing surface that defines a non-parallel angle with the radially inner bowl surface where the radially inner bowl surface meets the radially innermost edge of the radially inner mating surface.

Abstract: A pre-finished piston part is disclosed that may be used to form a piston assembly. A pre-finished piston may include a lower part defining a piston axis, the lower part having a skirt and forming a lower surface of a cooling gallery. The lower part may include a radially inner bowl surface defining a lower part radially inner mating surface. The pre-finished piston assembly may further include an upper part having a radially outer bowl surface meeting the radially inner bowl surface at a radially inner joint. The upper part may include a radially inner wall defining a radially inner upper part mating surface. The radially inner wall may define a radially inwardly facing surface that defines a non-parallel angle with the radially inner bowl surface where the radially inner bowl surface meets the radially innermost edge of the radially inner mating surface.

Abstract: A pre-finished piston part is disclosed that may be used to form a piston assembly. A pre-finished piston may include a lower part defining a piston axis, the lower part having a skirt and forming a lower surface of a cooling gallery. The lower part may include a radially inner bowl surface defining a lower part radially inner mating surface. The pre-finished piston assembly may further include an upper part having a radially outer bowl surface meeting the radially inner bowl surface at a radially inner joint. The upper part may include a radially inner wall defining a radially inner upper part mating surface. The radially inner wall may define a radially inwardly facing surface that defines a non-parallel angle with the radially inner bowl surface where the radially inner bowl surface meets the radially innermost edge of the radially inner mating surface.

Abstract: A method and system of inertia friction welding that enables the production of inertia friction welds in which the final upset can be controlled to an operator specified target. The method utilizes any profile-based upset control technique, including but not limited to torque modulation and pressure (load) modulation. The method dynamically modifies the profile upset setpoints to systematically drive the upset formation to produce a weld with the targeted upset. The method and system also enables the production of inertia friction welds in which the final welded part length can be controlled to an operator specified target. The system and associated method comprises inertia friction welding a pair of sample parts to form a sample weld while acquiring data relating to the formation of the sample weld.

Abstract: A method and system of inertia friction welding that enables the production of inertia friction welds in which the final upset can be controlled to an operator specified target. The method utilizes any profile-based upset control technique, including but not limited to torque modulation and pressure (load) modulation. The method dynamically modifies the profile upset setpoints to systematically drive the upset formation to produce a weld with the targeted upset. The method and system also enables the production of inertia friction welds in which the final welded part length can be controlled to an operator specified target. The system and associated method comprises inertia friction welding a pair of sample parts to form a sample weld while acquiring data relating to the formation of the sample weld.

Abstract: A method and system of direct drive friction welding to reduce upset variation or reduce welded part length variation and a method and system of inertia friction welding to reduce upset variation. The system comprises a spindle which is configured to engage a part and a drive which is operatively connected to the spindle to rotate the spindle, and associated microprocessor based devices to store data and command the drive. The method comprises a sample friction weld of parts, and storing data in connection therewith, in order to generate a profile of upset versus speed. The method then, through the modulation of spindle drive torque, uses this profile for additional production friction welds having upset versus speed characteristics consistent with the profile of the sample weld during a deceleration phase of the friction weld.

Abstract: A method and system of inertia friction welding of work parts welded with a specified angular orientation with respect to each other. The method and apparatus comprises loading a sample work part into a rotating chuck attached to a spindle and loading another sample work part into a non-rotating chuck and then applying torque to the spindle to accelerate the spindle to achieve a predetermined first rotational speed. Next, the sample work parts are inertia friction welded together to form a sample weld. Then, the system measures and stores data related to the deceleration of the spindle during the sample inertia friction weld. The welded sample work parts are removed from the rotating and the non-rotating chucks. The system then calculates a sample deceleration profile of the spindle from the data acquired during the formation of the sample weld. Next, a production work part is loaded into the rotating chuck and another production work part is loaded into the non-rotating chuck.