| 摘要 |
The invention relates to a boring device comprising a rotary percussion external hammer drill (1) which is arranged outside the borehole (2) and with which boring energy can be generated. The boring device also comprises a boring rod (5) which is connected to the rotary percussion external hammer drill (1) on one side and with which the boring energy can be transferred from the rotary percussion external hammer drill (1) in a direction toward the bottom (3) of the borehole. In addition, a bore-crown (7) is provided which is connected to the end of the boring rod (5) located at the bottom of the borehole, and with which the boring energy transferred thereupon by the boring rod (5) can be converted into a boring advance. In order to improve the flushing of the borehole and the removal of drillings which accumulate on the bottom (3) of the borehole during boring advance, the inventive boring rod (5) has an inner rod (4) with which the boring energy can be transferred from the rotary percussion external hammer drill (1) to the bore-crown (7), and in which a first flushing channel (10) is configured which extends from a first flushing medium feed connection (11) up to the bore-crown (7). In addition, the boring rod comprises an outer rod (6) which encircles said inner rod (4) in an interspaced manner and which constructs a second flushing channel (26) between the inner casing surface thereof and the outer casing surface of the inner rod (4). Said second flushing channel is connected, on the entry side, to a second flushing medium feed connection (27) and is connected, on the outlet side, to the annulus (17) configured between the outer casing surface of the outer boring rod (6) and the borehole wall (18) via the borings (31) which penetrate the outer rod (6). |
