A machining tool incorporates a shaft having a first end configured to fit into a machining collet. A cutting portion extends from a second end of the shaft. A residual stress inducer is located between the first and second ends and includes a torsion element joined to the shaft at a connection end. A carbide tip is present on a free end opposite the connection end and the torsion element is configured such that a selected rotational speed, altered from a normal cutting speed, causes the carbide tip of the torsion element to contact a workpiece surface.

A machining tool incorporates a shaft having a first end configured to fit into a machining collet. A cutting portion extends from a second end of the shaft. A residual stress inducer is located between the first and second ends and includes a torsion element joined to the shaft at a connection end. A carbide tip is present on a free end opposite the connection end and the torsion element is configured such that a selected rotational speed, altered from a normal cutting speed, causes the carbide tip of the torsion element to contact a workpiece surface.

Devices (10) for burnishing a surface (111, 112) on an object (108) includes a body (11) having a passageway (25), an accumulator piston (65) mounted on the body for sealed sliding movement within the passageway, a coarse adjustment screw (13) mounted on the body, a resilient member (14) acting between the coarse adjustment screw and the accumulator piston, a lever (12) mounted on the body, a chamber (32) communicating with the accumulator piston, an actuator piston (78) mounted on the body for sealed sliding movement within a cylindrical opening (41) toward and away from the rearward portion (48) of the lever, and a roll (15) rotatably mounted on the forward portion (49) of the lever. The devices are adapted to be mounted on a machine tool (105) and moved toward the object to burnish the surface with controllable force along the required length of the surface.

Devices (10) for burnishing a surface (111, 112) on an object (108) includes a body (11) having a passageway (25), an accumulator piston (65) mounted on the body for sealed sliding movement within the passageway, a coarse adjustment screw (13) mounted on the body, a resilient member (14) acting between the coarse adjustment screw and the accumulator piston, a lever (12) mounted on the body, a chamber (32) communicating with the accumulator piston, an actuator piston (78) mounted on the body for sealed sliding movement within a cylindrical opening (41) toward and away from the rearward portion (48) of the lever, and a roll (15) rotatably mounted on the forward portion (49) of the lever. The devices are adapted to be mounted on a machine tool (105) and moved toward the object to burnish the surface with controllable force along the required length of the surface.

A method for smoothing surface roughness within an internal passageway is disclosed. In various embodiments, the method comprises developing a first sphere progression through a length of the internal passageway, each sphere within the first sphere progression having a first sphere diameter greater than or equal to a diameter of the internal passageway; and developing a second sphere progression through the length of the internal passageway, each sphere within the second sphere progression having a second sphere diameter greater than the first sphere diameter, whereby the inner surface of the internal passageway is smoothed, first by the first sphere progression and then by the second sphere progression.

A processing method according to one aspect incudes preparing a metal workpiece having a hole that opens to a surface thereof, filling the hole with processing media, and applying an external force to the processing media to apply a compressive residual stress to an inner surface of the hole.

A combined skiver and a smooth rolling tool with a skiver head and behind this a smooth rolling head, wherein between the skiver head and the rolling head an exclusive torque transmitting coupling is located which restricts the allowable axis shaft offset and/or the angular position of the axes of the rolling head and skiver head, to which the rolling head is connected, characterized in that the skiver head (2) is guided through a workpiece bore via a hydrostatic guideway.

The burnishing part includes: a mandrel; burnishing rollers; a frame; an adjustment member that presses the frame axially from one end thereof to adjust the axial position of the frame with respect to the mandrel; and an elastic member that is arranged axially on the other side of the frame to support the frame. The reaming part includes: a base part that is detachably attached to the mandrel; and machining blades that are formed integrally with the base part. This results in providing a combined machining tool that is capable of machining an inner peripheral surface of a workpiece having a smaller diameter, and a machining method using the same.

Provided is a roller burnishing tool device including a shank; a housing connected to the shank, a connected position of the housing relative to the shank being adjustable; a roller support member supported to be capable of rotating relative to the housing and attached to follow a movement of the housing in a case of adjusting the connected position; tapered rollers supported by the roller support member; a mandrel having a tapered portion matched with the tapered rollers and movable relative to the roller support member; and a tool diameter following mechanism connecting the shank and the mandrel, having a lead groove formed spirally in a front portion of the shank, a pin member capable of moving along the lead groove, a pin member insertion hole formed in the mandrel to insert the pin member therein, and a biasing unit biasing the mandrel forward.

Internal and external screw thread burnishing assemblies are provided. In the internal screw thread burnishing assembly, diametrically opposed removable cartridges carrying burnishing wheels are received in cavities of a support structure axially movable into the space circumscribed by the internal screw thread. Fluid pressure is utilized to forcibly translate the cartridges radially outwardly to place their burnishing wheels into burnishing engagement with the internal screw thread, with a spring structure resiliently biasing the cartridges toward retracted orientations thereof within the support structure. In the external screw thread burnishing assembly, burnishing wheels are carried on the outer ends of pivotally supported arms which may be pivoted by fluid pressure to drive the burnishing wheels into burnishing engagement with diametrically opposite portions of the external screw thread, with a spring structure resiliently biasing the arms pivotally away from one another.