High pressure presses, components for high pressure presses and related methods are provided herein. In one embodiment of the invention, a press base may include a piston cavity formed in the press base and a piston cavity sleeve positioned in the piston cavity. The piston cavity sleeve may include a wall having an outer surface and an inner surface opposite the outer surface. The piston cavity sleeve may further include a floor having an upper surface and a lower surface opposite the upper surface. An outer radius may be formed at a juncture of the outer surface of the wall and lower surface of the floor and an inner radius may be formed at a juncture of the inner surface of the wall and upper surface of the floor. The inner radius may exhibit a radius of curvature that is greater than a radius of curvature of the outer radius.

A piston and method of construction is provided. The piston includes a top part fixed to a bottom part. The top part has an uppermost surface with annular inner and outer upper joining surfaces depending therefrom. The bottom part has a pair of pin bosses with pin bores aligned with one another along a pin bore axis; a pair of upwardly extending annular inner and outer lower joining surfaces and a combustion bowl wall. Inner and outer weld joints fix the inner and outer upper and lower joining surfaces to one another. An annular cooling gallery is formed laterally between the upper and lower joining surfaces. The inner weld joint joining the top part to the bottom part is located within the combustion bowl wall and configured to minimized the compression height of the piston.

A press base may include a piston cavity formed in the press base and a piston cavity sleeve positioned in the piston cavity. The piston cavity sleeve may include a wall having an outer surface and an inner surface opposite the outer surface. The piston cavity sleeve may further include a floor having an upper surface and a lower surface opposite the upper surface. An outer radius may be formed at a juncture of the outer surface of the wall and lower surface of the floor and an inner radius may be formed at a juncture of the inner surface of the wall and upper surface of the floor. The inner radius may exhibit a radius of curvature that is greater than a radius of curvature of the outer radius.

Embodiments of the present invention include a press base assembly, a strengthening ring for use with press bases and related methods. In one embodiment, a press base assembly includes a press base having a body that includes a piston cavity at one end. The body, at a second end opposite that of the piston cavity, may exhibit a desired geometry. A strengthening ring may be shaped, sized and configured to substantially mate with the geometry of the second end of the body and be placed thereover. For example, the geometry of the second end may be substantially circular exhibiting a particular diameter and circumference. The strengthening ring may have substantially circular internal surface sized and configured such that the strengthening ring is positioned on the second end of the body in a manner that results in an interference fit between the two components.

A high pressure press assembly along with related methods and components for the press assembly are provided. In one embodiment, a press assembly includes a first press base having one or more tie bar receiving holes extending therethrough. A second press base may also include one or more tie bar receiving holes extending therethrough. A tie bar extends between the first press base and the second press base. A tensioning assembly is operatively coupled to the tie bar to place the tie bar in tension.

Various embodiments of high pressure presses and related methods of manufacturing and operating such presses are described. In one embodiment, a cubic press is described having press bases with spacers disposed between adjacent press bases. Sets of two or more tie bars are also disposed between adjacent press bases. The tie bars are placed in a state of compression while the spacers are placed in a state of compression. During operation, the press bases may become displaced relative to one another such that additional tension is experience by the tie bars while the amount of compression experienced by the spacer is reduced. The tie bars exhibit a relatively small cross-sectional area as compared to the cross-sectional area of the spacer.

A method for the production of a piston made of steel, for an internal combustion engine, in which the upper piston part is produced using the forging method, and the lower piston part is produced using the forging or casting method, and they are subsequently welded to one another. To simplify the production method and make it cheaper, the upper piston part is forged using the method of hot forming and of cold calibration, to finish it to such an extent that further processing of the combustion bowl and of the upper cooling channel regions can be eliminated.

A piston assembly comprises a piston body, a connecting rod, and a wrist pin. The piston body includes a pair of first cross bores presenting a piston sliding surface. The connecting rod includes a second cross bore presenting a rod sliding surface which is axially aligned with the first cross bores of the piston body. A wrist pin is disposed in the aligned cross bores and couples the piston body to the connecting rod. The wrist pin also presents a pin sliding surface facing the rod sliding surface and the piston sliding surfaces. A coating is applied to at least one of the sliding surfaces, such as by dipping, brushing, atomizing, spraying, printing, or screen printing. The coating includes a polymer matrix, such as polyamide imide (PAI), and hard particles, such as Fe.sub.2O.sub.3, disposed throughout the polymer matrix. The hard particles have a hardness of at least 600 HV/0.5.

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.

A valve component includes a first disk-shaped joining part and a second disk-shaped joining part. The first disk-shaped joining part has a first opening and has an elevation in a first region of the first disk-shaped joining part which runs at least partially peripherally around the first opening. The second disk-shaped joining part is joined to the first disk-shaped joining part and has a second opening which together with the first opening defines a channel for flow of a fluid medium therethrough. The second disk-shaped joining part further has a depression in a second region of the second disk-shaped joining part which runs at least partially peripherally around the second opening and which opposes the first region of the first disk-shaped joining part. The elevation interacts with the depression in sealing fashion.