| 摘要 |
The present invention relates to a rock drilling tool (10), a reamer means (12) and a body element (11). The drilling tool (10) is foremost intended for down-the-hole drilling by drilling a hole in front of a trailing casing (13). The drilling tool comprises a body element (11) and a reamer means (12). The body element (11) comprises a central pilot bit (16), a shank (15) and a guiding means (18) for guiding the drilling tool and the casing (13) relative to each other. The guiding means (18), the shank (15) and the pilot bit (16) constitute a one-piece unit, wherein the guiding means (18), the shank (15) and the pilot bit (16) cannot be dismounted relative to each other. The reamer means (12) is divided and has, in mounted position, an inner diameter (D2) which is smaller than the largest diameter (D, D1) of both the guiding means (18) and the pilot bit (16).
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