A method of reprocessing a metal product includes a welding step for welding a dummy member to the metal product, a reprocessing step for reprocessing the metal product in a state where the metal product is supported by a first support unit and the dummy member is supported by a second support unit, and a removal step for removing the dummy member from the metal product after the reprocessing step. The reprocessing of the metal product while the metal product is fixed is thus enabled without restriction from the shape of the metal product.

A complex machine tool for cylindrical workpieces has a bed, a headstock assembly, at least one supporting assembly, and at least one machining assembly. The bed has three tracks being respectively a first track, a second track, a third track arranged in order. Each one of the three tracks defines a respective guiding direction, and the three guiding directions of the three tracks are mutually parallel. The headstock assembly is connected to the bed, and is located near one of two ends of the second track. The at least one supporting assembly is mounted on one of the three tracks and is used for supporting the cylindrical workpiece. The at least one machining assembly is mounted on one of the three tracks, is slidable along the track, and is located on a position at a spaced interval from the at least one supporting assembly.

A tooling assembly for a lathe machine includes a tool platform configured to be mounted on the lathe machine, a milling tool holder fixedly secured to the tool platform and workable to releasably secure a thread milling tool therein, and a milling tool drive. The milling tool drive is operatively connected to the milling tool holder and operable to rotate the milling tool holder independently of a work holder to mill threads on the workpiece when a pipe thread milling tool is secured in the milling tool holder. Computer numerical control threading lathes and methods of milling threads in tubular workpieces are also described.

A machine tool includes a first main shaft, a first drive source for moving the first main shaft, a second main shaft, a second drive source for moving the second main shaft, and a control means for carrying out a control so as to bring the workpiece held by the first main shaft and the workpiece held by the second main shaft into contact with each other while rotating them relative to each other, thereby to carry out the friction-heating, and to stop the relative rotation of the pair of workpieces and move only the second main shaft in the axial direction while holding the first main shaft stationary, thereby to carry out friction-welding of the pair of workpieces. The control means controls the operation of the first drive source upon the friction-welding of the pair of workpieces, so as to maintain the axial position of the first main shaft.

A turning method for performing a turning on a workpiece in a machine tool includes: feeding a tool in a rotation axis direction and/or a radial direction of a workpiece while rotating the workpiece, the tool including an insert having a side cutting edge, the side cutting edge including a straight line portion; and feeding the tool in the rotation axis direction and the radial direction and in a predetermined inclined direction that is non-parallel to a final machining surface of the workpiece, so as to perform a turning such that a cutting edge angle as an angle formed by the straight line portion of the side cutting edge and the inclined direction becomes less than 90°.

A turning method for performing a turning on a workpiece in a machine tool includes: feeding a tool in a rotation axis direction and/or a radial direction of a workpiece while rotating the workpiece, the tool including an insert having a side cutting edge, the side cutting edge including a straight line portion; and feeding the tool in the rotation axis direction and the radial direction and in a predetermined inclined direction that is non-parallel to a final machining surface of the workpiece, so as to perform a turning such that a cutting edge angle as an angle formed by the straight line portion of the side cutting edge and the inclined direction becomes less than 90°.

Provided is a machining method for a workpiece that is rotated in a machine tool having a main spindle, in which modification of the machine tool is not necessary when machining the workpiece. The machining method for the workpiece includes: a first mounting step in which a workpiece holder that is holding the workpiece is mounted onto the main spindle of the machine tool; and a first machining step in which the main spindle is rotated and the workpiece is machined by a first tool installed on a table of the machine tool.

Provided is a machining method for a workpiece that is rotated in a machine tool having a main spindle, in which modification of the machine tool is not necessary when machining the workpiece. The machining method for the workpiece includes: a first mounting step in which a workpiece holder that is holding the workpiece is mounted onto the main spindle of the machine tool; and a first machining step in which the main spindle is rotated and the workpiece is machined by a first tool installed on a table of the machine tool.

A manufacturing machine is capable of subtractive manufacturing and additive manufacturing for a workpiece. The manufacturing machine includes: a first headstock and a second headstock disposed in a machining area and configured to hold a workpiece; a tool spindle and a lower tool rest disposed in the machining area and configured to hold a tool to be used for subtractive manufacturing for the workpiece; an additive manufacturing head configured to discharge a material during additive manufacturing for the workpiece; a workpiece gripper configured to grip the workpiece during transportation of the workpiece into and out of the machining area; and a robot arm on which the additive manufacturing head and the workpiece gripper are mountable. Accordingly, the manufacturing machine improving the productivity in the simple and easy manner is provided.

A manufacturing machine is capable of subtractive manufacturing and additive manufacturing for a workpiece. The manufacturing machine includes: a first headstock and a second headstock disposed in a machining area and configured to hold a workpiece; a tool spindle and a lower tool rest disposed in the machining area and configured to hold a tool to be used for subtractive manufacturing for the workpiece; an additive manufacturing head configured to discharge a material during additive manufacturing for the workpiece; a workpiece gripper configured to grip the workpiece during transportation of the workpiece into and out of the machining area; and a robot arm on which the additive manufacturing head and the workpiece gripper are mountable. Accordingly, the manufacturing machine improving the productivity in the simple and easy manner is provided.