Abstract: The invention relates to a device at a rotator and grapple unit intended for tree handling and suspended at the end of a boom. The rotator (8) and grapple (11) are connected each to a pair of flexible operating lines (6,7 and, respectively, 9,10) from a hydraulic pump (1) via a control valve (3). For rendering possible completion of the unit with a hydraulic sawing device without adding two additional hydraulic hoses for this purpose, which would give rise to problems due to the combined bending and rotary movement at the crane tip and resulting heavily increased strains and wear on a bundle consisting of six hoses, according to the invention a branch line (13) is taken from the operating line (10) used for closing the grapple (11), which branch line is located in a place after the rotator (8). The branch line (13) extends to a hydraulic sawing device (15,16) via a pressure-sensing valve (14).

Abstract: Cutting horizontal, cantilevering objects of splittable material, such as de-barked tree trunks and the like is carried out with the aid of a guided, endless circulating saw chain (10), the upper cutting part of which is moved from below and upwards through the object. The lower edge portions of the cut surfaces at the cut are allowed to bear against each other under the action of the bending moment of the cantilevering object, while the return portion of the saw chain in the cutting area is kept free from the cut surfaces. The saw chain is guided by a chain guide (12) extending curvilinearly under the object and guides the return part of the chain. The chain guide and the guided return part are both outside and below the object during the whole of the cutting operation, while the upper cutting portion of the chain runs straight between the end points of the curved portion of the chain guide.