<p>The device is fixed to a tractive machine (3) and has inverted U-shaped frame (6) of parts comprising cutting beam with driven cutting tools (14). An upper frame part (9) and vertical frame part (8) removed from the chassis (2) of the tractive machine are pivotable in relation to a second vertical frame part (7), rigidly arranged on the inverted U-shaped frame. The cutting tools of the opposing vertical cutting beams (11,13) in pivoting of the frame parts (8,9) are always directed parallel to one another. The frame parts are pivotable by means of an adjustment device in or opposed to the travel and work direction.</p>