Abstract: A method for connecting components using friction stir welding and a device for carrying out the stir friction welding method. A friction stir welding tool having a pin and a shoulder rotates about an axis of rotation and is moved along an advancement direction to connect the components. To obtain a high-quality weld with a simultaneously high welding speed, a friction stir welding tool having a shoulder movable relative to the pin is used and a rotational speed of the pin about the axis of rotation corresponds to at least 1.15 times, preferably at least 1.5 times, in particular 2 to 12 times, the rotational speed of the shoulder about the axis of rotation. The advancement speed is at least 1.0 m/min, preferably 2.0 m/min to 15 m/min.

Abstract: A friction stir welding tool for a machine tool having a frame and a spindle rotatable relative to the frame. The friction stir welding tool includes a pin, a shoulder, and a drive shaft connectable to the spindle to set the pin and the shoulder in rotational motion about a rotation axis, wherein the shoulder is rotatable relative to the pin about the rotation axis. To obtain different speeds of the pin and shoulder in a simple and robust manner, a planetary transmission having a ring gear, a planet carrier, and a sun gear is connected to the drive shaft, pin, and shoulder. The pin or the shoulder is connected to the planet carrier so that the pin and shoulder are set in rotation about the rotation axis at different rotational speeds, but in the same rotation direction, by driving the drive shaft by the spindle.