| 摘要 |
A drill column for producing bores in the roof area of a coal face is known. The drill column has no flushing means. In order to keep the accumulation of dust as small as possible, especially at the face, the known drill column is provided according to the invention with an axial through-channel which consists of channelled end-side insert bodies 4, 5 as well as an inner tube 32 connecting the insert bodies 4, 5. In this way, a continuous flushing channel 28, 32 is created but without impairing the sound coupling between two drill pipes 1, 1a in the longitudinal direction and the direction of rotation. <IMAGE>
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