expansion bolt


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expansion bolt

[ik′span·shən ‚bōlt]
(design engineering)
A bolt having an end which, when embedded into masonry or concrete, expands under a pull on the bolt, thereby providing anchorage.

expansion bolt

expansion bolts
An anchoring device having an expandable socket that swells as a bolt is tightened into it; used in masonry walls for attaching timber, etc.
References in periodicals archive ?
Expansion bolts (also called molly bolts) are similar to anchors, except that once the screw is run through the anchor unit, the unit expands behind the wall, creating a true anchor that won't allow the screw to be pulled out by the weight of the item.
Using the longer nails, anchor the two back wall supports to studs (if the small end supports don't span two studs, you may need expansion bolts to secure them).
Service and installation of anchors 234 stainless steel with a capacity of 23kn, anchored with expansion bolts and reinforced epoxy anchor to optimize both by physical methods such as chemical.
Woodscrews attach the central piece to a wall stud; expansion bolts secure branches to the gypsum board wall.
When plants reach full bloom, in early July, they are secured to the wall with clips and expansion bolts (see photograph at bottom right).
7 CY concrete box culverts; 18 SF structural repair of concrete (depth greater than 5"); 88 expansion bolts.
Sockets may require expansion bolts instead of the screws supplied.
Tenders are invited for Annual contract for fixing expansion bolts, strenghening and special repairs to various structure and machine foundation at CSTPS, Chandrapur