Expanding plug has slotted spread sleeve with annular groove - and spread element with together at least three different:conicity portions

摘要

Expandable plug (1) comprises a spread sleeve (2) with female screw end (3) to receive an anchor bolt, which sleeve is provided with longitudinal slots or break grooves in the expanding region, and a spread element (8) which is driven into the sleeve to spread it. The sleeve bore and the element are, between them, provided with at least three conical portions (4,6 and 10,12) with different coincities. The sleeve has at least one circumferential groove (13) in its expanding region, the ratio of groove depth to width being at least 1 to 5. The groove(s) are free of notches and the most forward groove (13) is positioned near the forward end of the sleeve so that it can be produced in one operation together with the forward chamfer (2a).