Abstract: The present invention relates to a composite tool comprising at least two milling tool holders, to a milling tool holder for such a composite tool and to a milling drum equipped with such milling tool holders. According to the present invention, a milling tool holder is utilized for supporting a tool replacement device during tool replacement of the milling tool in the milling tool holder that precedes it in the peripheral direction. To this end, according to the present invention, a supporting area is provided on the base element of the milling tool holder, which supporting area provides appropriate stabilized guidance for the tool replacement device.

Abstract: A mining device for subsurface extraction of raw materials off rocks includes bracing means for the reversible bracing of the mining device in a hollow space, a frame, and tunneling means stationarily connected with the bracing means, whereby the frame is movable by the tunneling means in a predefined direction. A rotatable roller is arranged on the frame, at the circumference of which cutting tools and clearing devices are arranged such that a rectangular mining cross-section can be created and such that the mining device and also the frame of the mining device is movable into a mining tunnel created by these cutting tools.

Abstract: A machine for improved excavation of underwater rock that eliminates failures due to over-stressed cutting teeth by positioning each hardened tooth for optimized Kinetic Energy. It has a plurality of blades, each with a hub and a plurality of spokes connecting the hub to a rim. Teeth are mounted on the leading edge of each blade approximately equidistant from the cutter axis of rotation, allowing each tooth to have the proper combination of velocity and cutting force required to shatter massive, hard rock. As a result, all teeth have approximately the same peripheral velocity; have adequate Kinetic Energy to shatter rock upon impact, and are subject to approximately the same maximum stress during rock excavation.

Abstract: A method for detaching a manhole frame (7) that is embedded in a road surface, wherein the manhole frame (7) is cut horizontally starting from the inside, without significant exposure of the outside area surrounding the manhole frame (7), by using a horizontally oriented rotating cutting blade (15) that performs eccentric circumferential runs along the inside of the manhole frame.