A T-shaped tool is configured by fastening a head having cutting blades to a cylindrical shank, the shank is made of cemented carbide and has a tapered male thread formed at a tip end portion thereof, the tapered male thread becomes smaller in diameter toward the tip end, and the head is made of steel and has a tapered female thread formed therein, and the tapered female thread comes into engagement with the tapered male thread.

A screw-in tool and a tool holder for such a screw-in tool. The screw-in tool contains a tool head and a tool shank having an outer thread and a supporting region arranged between the tool head and the outer thread. The supporting region is formed by two conical bearing faces having different cone angles.

A replaceable face-milling head configured for rotating about a central rotation axis A.sub.R. The head includes a cutting portion and an integrally formed threaded shank-connector portion, the latter of which being configured for connecting to a shank. A length-diameter ratio LDR, defined as a cutting portion length L.sub.C divided by a cutting portion diameter D.sub.E, fulfills the condition: LDR≦1.00.

A rotatable chuck for clamping a shank portion of a rotatably operating machining tool includes a rotatable chuck body provided with a cylindrical bore concentric with a rotation axis of the chuck body. The circumferential surfaces of a clamping portion of the bore are arranged to apply a clamping force around the circumference of the shank portion of the tool when it is mounted in the chuck to fixate the tool in the chuck. The chuck is provided with auxiliary pull out preventing means for preventing inadvertent pull out of the tool in the axial direction of the bore during machining operation, as well as auxiliary rotary preventing means for preventing inadvertent rotation in at least one direction in relation to the chuck during machining operation. The auxiliary pull out and rotary preventing means include an attachment member positionable in an inner portion of the bore and attachable to the shank portion to be clamped, such that the tool and the attachment member will be prevented from being pulled apart in the axial direction and from being rotated in at least one direction in relation to each other.

A tool arrangement with a screw-in tool and a tool receiver, the screw-in tool having a thread for engagement in a counter thread on the tool receiver. The counter thread and the thread have different thread contours and therefore, in the screwed condition, these adapt to one another by elastic deformation.

A rotary cutting tool includes a replaceable cutting head and a tool holder. The replaceable cutting head includes a forward cutting portion and a rearward mounting portion. The mounting portion includes a male coupling member that includes a straight external thread. The tool holder includes a female coupling member that includes a conical internal thread. When the rotary cutting tool is in a locked position, the external thread is threadingly engaged with the internal thread.

A rotary cutting tool includes a replaceable cutting head and a tool holder. The replaceable cutting head includes a forward cutting portion and a rearward mounting portion. The mounting portion includes a male coupling member that includes a back-tapered conical external thread. The tool holder includes a female coupling member that includes an internal thread. When the rotary cutting tool is in a locked position, the external thread is threadingly engaged with the internal thread.

A rotary cutting tool includes a replaceable cutting head and a tool holder. The replaceable cutting head includes a forward cutting portion and a rearward mounting portion. The mounting portion includes a male coupling member that includes a back-tapered conical external thread. The tool holder includes a female coupling member that includes an internal thread. When the rotary cutting tool is in a locked position, the external thread is threadingly engaged with the internal thread.

A T-shaped tool is configured by fastening a head having cutting blades to a cylindrical shank, the shank is made of cemented carbide and has a tapered male thread formed at a tip end portion thereof, the tapered male thread becomes smaller in diameter toward the tip end, and the head is made of steel and has a tapered female thread formed therein, and the tapered female thread comes into engagement with the tapered male thread.

A rotatable cutting tool, which extends along a tool axis defining an axial direction, includes a cutting formation in a first axial longitudinal end region, which is configured for material ablation on a workpiece, and includes a screw-connection formation in a second axial longitudinal end region opposing the first, which is configured for screw connection with a coupling unit. The cutting tool includes key-contact surface formations diametrically opposing each other with respect to the tool axis, which are configured for torque-transmitting abutting engagement with key surfaces of a key. Each of the key-contact-surface formations includes at least two key-contact surface regions provided with spacing from each other in the circumferential direction about the tool axis, which key-contact surface regions are inclined away from each other such that they form a vertex projecting away from the tool axis.