A process for cold working of the inner surface of a bore in a centrifugal compressor wheel along only a fractional portion of the bore length (i.e., along less than a full axial length of the bore), thereby creating a zone of compressive residual hoop stress in the metal surrounding the bore where the wheel needs the beneficial residual stress. The process purposefully avoids cold working of the bore at locations adjacent to high-stress areas and features of the wheel, where cold working in such locations could negatively impact the wheel's overall life.

A hybrid threading tap includes a reamer portion and a thread cutting portion having a plurality of cutting teeth. The thread cutting portion is arranged with the reamer portion along the longitudinal axis. The reamer portion is configured to be advanced within a hole of a workpiece to plastically deform and expand the hole to an expanded hole and provide the expanded hole with a zone of residual compressive stress. The plurality of cutting teeth is configured to cut a threading into the expanded hole within the zone.

A coining apparatus for forming a sealing surface in an end portion of a tube includes an inner portion having a first bead forming surface and an outer portion having a second bead forming surface. The outer portion is arranged concentric to the inner portion with a radial gap formed therebetween. The first bead forming surface and the second bead forming surface each lead towards the gap and are tapered in opposing radial directions. The radial gap provides a pathway for a flow of deformed tube material or a flow of fluid during the formation of an engaging bead in the sealing surface as caused by engagement of the first bead forming surface and the second bead forming surface with the end portion of the tube. The formation of the engaging bead via the coining process results in at least a portion of the engaging bead being work hardened.

Systems and methods for coldworking metal are described that reduce the axial flow of metal and increase the radial/tangential flow, thereby improving the fatigue life at an aperture. A tool is inserted through an aperture and its travel speed is reduced when in contact with the metal to reduce axial plastic flow. A sensor as part of the motive system moving the mandrel can sense when the tool contacts the metal and reduces the speed of the tool. The tool may move more quickly when not in contact with the metal to reduce working time than when the mandrel is working the metal. The coldworking tool engages the metal at the aperture at a speed of less than the speed which results in the time duration for the mandrel engaging the metal at the aperture for 35 second per inch of metal thickness at the aperture.

A method for roughening a cylinder bore wall to be coated of a component, at least one groove, running around the central longitudinal axis, and at least one associated groove web, are generated such that the at least one groove web, in a radial direction directed toward the central longitudinal axis, forms first undercuts for a coating which is to be applied. Axial grooves running in the cylinder bore wall transversely to the at least one groove are generated such that the at least one groove web, in a peripheral direction about the central longitudinal axis, forms respective second undercuts for the coating which is to be applied. An adhesion of the coating which is to be applied, in the peripheral direction, is improved, so that stress cracks or detachments owing to a different thermal expansion of the component and of the coating which is to be applied are avoided.

A hybrid threading tap includes a reamer portion and a thread cutting portion having a plurality of cutting teeth. The thread cutting portion is arranged with the reamer portion along the longitudinal axis. The reamer portion is configured to be advanced within a hole of a workpiece to plastically deform and expand the hole to an expanded hole and provide the expanded hole with a zone of residual compressive stress. The plurality of cutting teeth is configured to cut a threading into the expanded hole within the zone.

A method for the autofrettage of a workpiece may involve arranging the workpiece between a first securing means and a second securing means, and applying high-pressure fluid to an internal volume of the workpiece that is formed between the first and second securing means. A die or ram may be driven into the internal volume through an inlet in the first securing means. Consequently, as a result of the ram being advanced, not only is a fluid pressure generated in the internal volume, but also the workpiece is mechanically autofrettaged by way of the ram. A device may be employed to perform such hydromechanical autofrettage of the workpiece.

An installation tool assembly includes a workpiece and a tool. The workpiece includes a first wall having an aperture and a second wall spaced from the first wall relative to a first axis to present an access point therebetween. The installation tool assembly includes a fastener disposed in the aperture of the first wall at an initial position. The fastener includes a hole and a fastener locking feature disposed inside the hole. The tool includes a tool locking feature that is configured to engage the fastener locking feature to secure together the fastener and the tool in the initial position. The tool is operable to pull the fastener farther through the aperture into an interference fit with the first wall in an installed position. A tooling assembly includes the tool and the fastener. A method of installing the fastener to the workpiece uses the tool.

An installation tool assembly includes a workpiece and a tool. The workpiece includes a first wall having an aperture and a second wall spaced from the first wall relative to a first axis to present an access point therebetween. The installation tool assembly includes a fastener disposed in the aperture of the first wall at an initial position. The fastener includes a hole and a fastener locking feature disposed inside the hole. The tool includes a tool locking feature that is configured to engage the fastener locking feature to secure together the fastener and the tool in the initial position. The tool is operable to pull the fastener farther through the aperture into an interference fit with the first wall in an installed position. A tooling assembly includes the tool and the fastener. A method of installing the fastener to the workpiece uses the tool.

Processing tool for processing a surface of a workpiece. The processing tool includes a tool body which defines a tool axis. At least one first roll element, which is borne by the tool body, is rotatable around a first roll element axis and has a first outer surface with a rough surface structure in at least one first working section configured for rolling contact with the workpiece surface. Further, at least one second roll element, which is borne by the tool body, is rotatable about a second roll element axis and has a second outer surface that, in at least one second working section configured for a rolling contact with the workpiece surface, has a distance (r2) to the tool axis, which is less than a distance (r1) of the at least one first working section to the tool axis.