Abstract: A hydraulic hammer having a sealing bushing includes a percussion piston that delivers strokes to a tool. A lower part of the percussion piston is sealed with respect to a frame by the sealing bushing, which includes one or more lower seals. The sealing bushing does not contribute to the bearing of the percussion piston and it is arranged in place through the lower end of the hydraulic hammer.

Abstract: The invention relates to a hydraulic hammer comprising a percussion piston (12) for delivering strokes to a tool (8). The lower part of the percussion piston is sealed to the frame (9) by means of a sealing bushing (31) comprising one or more lower seals (15). The sealing bushing does not contribute to the bearing of the percussion piston and it is arranged in place through the lower end of the hydraulic hammer (1). Further, the invention relates to a tool bushing (28) into which the sealing bushing (31) is integrated.

Abstract: The invention relates to an arrangement in connection with a hydraulic breaking apparatus, the arrangement comprising a housing (4) placed around a percussion hammer (1), and a changeable wearing element (6) arranged at the lower part of the housing. The wearing element (6) receives blows and forces directed at the lower part of the housing (4). The wearing element (6) is fastened in such a way that it can be detached and changed easily and rapidly, if required. Further, the structure of the breaking apparatus may also be such that when the wearing element (6) is removed, it is possible to carry out the maintenance and repair operations of the lower frame (1b) of the percussion hammer without disassembling the upper frame (1a) of the percussion hammer.