Abstract: An arrangement for performing machining operations at the end faces of pipes includes a tool holder which is equipped with respective tools and is mounted at least for rotation on a carrier. The carrier is mounted on the machine frame for movement normal to the axis of the pipe which is clamped in a clamping device mounted on the machine frame, such that the axis of the pipe extends parallel to the axis of the tool holder. The tool holder has a central passage in which there is guided a spindle having a tapering end portion close to the pipe. A cylinder-and-piston unit pushes the spindle out of the passage and into the interior of the pipe so that the tapering end portion of the spindle becomes coaxially nested in the open end of the pipe, its axis and thus the axis of the tool holder then coinciding with the axis of the inner surface of the pipe. The carrier is then arrested in this working position by a pair of clamping devices, and the spindle is retracted into the passage.