SPREIZDUEBEL MIT SETZKRAFTANZEIGE

摘要

PCT No. PCT/EP84/00059 Sec. 371 Date Sep. 4, 1984 Sec. 102(e) Date Sep. 4, 1984 PCT Filed Mar. 2, 1984 PCT Pub. No. WO84/03741 PCT Pub. Date Sep. 27, 1984.An expanding bolt anchor with setting force indication, has a slitted expanding sleeve which can be expanded by at least one expander engaging the bore-internal end. In the bore-internal expander (26) there is held a threaded bolt (30) which is carried in a freely displaceable manner through the expanding sleeve (20), and a spacing sleeve (32) adjoining on the bore-orifice end, the bolt terminating in a bolt head (34) or in a nut threaded thereon, under which a washer (30) is disposed which lies on the upper side of a workpiece (10) to be fastened and through which the spacing sleeve displaceably passes. Between the spacing sleeve (32) and the spreading sleeve (20) there is disposed at least one sleeve-like tube section (36) of soft steel having a pronounced yield point, which bears along its surface a thin carburized layer which is hardened, and whose thickness is such that, when a bolt anchor-specific setting force is applied, compressive forces will prevail in this tube section at which the hardened layer breaks up, whereupon the rest of the material is axially compressed with perceptible reduction of the setting force.