Abstract: 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.

Abstract: 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.

Abstract: A method of constructing a piston, piston formed thereby, and piston body portions are provided. The method includes providing an upper crown portion at least one annular upper rib depending from the upper combustion wall to a free end having a tapered peak. The method further includes providing a lower crown portion having at least one annular lower rib extending to a free end having a tapered peak. Then, moving the upper crown portion and the lower crown portion toward one another and initiating contact between the upper crown portion and the lower crown portion at their respective tapered peaks. Then, continuing moving the upper crown and the lower crown further toward one another after making initial contact at their respective tapered peaks and forming a friction weld joint between the free ends of the at least one upper rib and the at least one lower rib free end.

Abstract: 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.

Abstract: 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.

Abstract: A method of constructing a piston, piston formed thereby, and piston body portions are provided. The method includes providing an upper crown portion at least one annular upper rib depending from the upper combustion wall to a free end having a tapered peak. The method further includes providing a lower crown portion having at least one annular lower rib extending to a free end having a tapered peak. Then, moving the upper crown portion and the lower crown portion toward one another and initiating contact between the upper crown portion and the lower crown portion at their respective tapered peaks. Then, continuing moving the upper crown and the lower crown further toward one another after making initial contact at their respective tapered peaks and forming a friction weld joint between the free ends of the at least one upper rib and the at least one lower rib free end.

Abstract: A method of constructing a piston, piston formed thereby, and piston body portions are provided. The method includes providing an upper crown portion at least one annular upper rib depending from the upper combustion wall to a free end having a tapered peak. The method further includes providing a lower crown portion having at least one annular lower rib extending to a free end having a tapered peak. Then, moving the upper crown portion and the lower crown portion toward one another and initiating contact between the upper crown portion and the lower crown portion at their respective tapered peaks. Then, continuing moving the upper crown and the lower crown further toward one another after making initial contact at their respective tapered peaks and forming a friction weld joint between the free ends of the at least one upper rib and the at least one lower rib free end.

Abstract: 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 firs piece is made through casting or forging, and the second piece is made through an additive manufacturing process, such as direct metal laser sintering.

Abstract: A piston has a piston body extending along a central axis. The piston body has an upper crown portion and a lower crown portion. The upper crown portion has an upper combustion wall and an at least one annular upper rib depending from the upper combustion wall to a free end. The lower crown portion has at least one annular lower rib extending to a free end that is fixed to the at least one upper rib and an inner gallery floor extending radially inwardly relative to the at least one lower rib. The upper crown portion has an upper post depending from the upper combustion wall along the central axis to a free end. The lower crown portion has a lower post extending upwardly from the inner gallery floor along the central axis to a free end. Together, the upper post and the lower post form a labyrinth passage.

Abstract: A method of friction welding a piston includes forming a piston body by friction welding an upper crown portion to a lower crown portion. At least one of the upper or lower crown portions is provided with a central support post extending along a central axis. The upper and lower crown portions have annular ribs radially outwardly from the central support post, with the ribs being aligned with one another. The method includes initiating a friction weld joint between a free end of the central support post and a corresponding surface opposite the free end of the central support post. Then, after initiating the weld joint between the central support post and the opposite surface, the method continues by then initiating a friction weld joint between aligned free ends of the ribs. Then, the friction weld joints are completed.

Abstract: 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.

Abstract: A method of friction welding a piston includes forming a piston body by friction welding an upper crown portion to a lower crown portion. At least one of the upper or lower crown portions is provided with a central support post extending along a central axis. The upper and lower crown portions have annular ribs radially outwardly from the central support post, with the ribs being aligned with one another. The method includes initiating a friction weld joint between a free end of the central support post and a corresponding surface opposite the free end of the central support post. Then, after initiating the weld joint between the central support post and the opposite surface, the method continues by then initiating a friction weld joint between aligned free ends of the ribs. Then, the friction weld joints are completed.

Abstract: A multi-axially forged mono-bloc piston includes a lower crown part forged of steel and including a pair of pin bosses and an integral skirt formed as one piece with the pin bosses 20. The lower crown part is friction welded to an upper crown part to form at least one closed oil gallery within the piston head. The lower crown part is forged in the longitudinal direction of the piston as well as laterally to impart longitudinal and laterally forged features of the piston. The laterally forged features may comprise undercut recesses formed in the piston skirt to reduce material in the overall piston structure. The lateral forging may also result in the piston skirt portion being discoupled from the piston head by laterally forged slots formed in the lower crown part 14 between the skirt and head.

Abstract: A piston has a piston body extending along a central axis. The piston body has an upper crown portion and a lower crown portion. The upper crown portion has an upper combustion wall and an at least one annular upper rib depending from the upper combustion wall to a free end. The lower crown portion has at least one annular lower rib extending to a free end that is fixed to the at least one upper rib and an inner gallery floor extending radially inwardly relative to the at least one lower rib. The upper crown portion has an upper post depending from the upper combustion wall along the central axis to a free end. The lower crown portion has a lower post extending upwardly from the inner gallery floor along the central axis to a free. Together, the upper post and the lower post form a labyrinth passage.

Abstract: A piston head has a top extending radially about a first axis and first and second pin bosses depending downwardly and defining first and second pin bores. A connecting rod includes a fork having first and second connecting bosses spaced apart from each other and defining first and second connecting bores. A piston skirt extends cylindrically and includes a bridge extending diametrically through the first axis defining a skirt bore for axial alignment with said pin bores and said connecting bores. The bridge is disposed between the first and second connecting bosses, which are disposed between the pin bosses. The pin bores are axially aligned with the connecting bores and with the skirt bore. A wrist pin extends within the pin bores and the connecting bores and the skirt bore along the second axis to interconnect the piston head and the connecting rod and the piston skirt.

Abstract: A monobloc piston assembly includes a piston head having a combustion bowl found in an upper surface and a ring belt found with a plurality of ring grooves. An oil cooling gallery is formed in the piston head adjacent the combustion bowl and ring belt. A pair of pin bosses are formed with aligned pin bores and a piston skirt is formed as an immovable piece with the pin bosses. An oil drainage groove is formed below the ring grooves and includes at least one drain hole open to the interior of the piston skirt.

Abstract: A piston particularly adapted for heavy-duty diesel engine applications is fabricated from separate parts having circumferentially extending joining surfaces that are heated prior to bonding to an elevated temperature sufficient to enable bonding of the joining surfaces, and thereafter the joining surfaces brought into contact with one another and twisted to attain a permanent metallurgical weld at the interface of the joining surfaces. The piston has radially spaced walls which are both welded simultaneously. The weld joints may lie in the same or different planes. Once joined, and while still hot, the parts may be pulled apart slightly to reduce the wall thicknesses at the weld joint.

Abstract: A piston particularly adapted for heavy-duty diesel engine applications is fabricated from separate parts having circumferentially extending joining surfaces that are heated prior to bonding to an elevated temperature sufficient to enable bonding of the joining surfaces, and thereafter the joining surfaces brought into contact with one another and twisted to attain a permanent metallurgical weld at the interface of the joining surfaces. The piston has radially spaced walls which are both welded simultaneously. The weld joints may lie in the same or different planes. Once joined, and while still hot, the parts may be pulled apart slightly to reduce the wall thicknesses at the weld joint.