| 摘要 |
The invention relates to a self-tapping drill screw that is screwable into a sheet piece and comprises a slotted head for accommodating a tool, a threaded shank, a slightly conically tapering hole-forming part and a hole-grinding part having a conical piece. The hole-grinding part has a radial shoulder that forms a hole and coaxially surrounds the conical piece, engagable with the sheet piece, in a ring-like manner, has a much larger diameter than the conical piece and merges with the hole-forming part via a rounded annular edge.
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