Definition

Noun: A type of fastener consisting of a bolt and a separate sleeve or mechanism that expands outward when the bolt is tightened. This expansion creates a secure grip within a pre-drilled hole in a base material like concrete, brick, or masonry, allowing the bolt to be anchored securely.

Usage

An expansion bolt is used to attach objects to solid, brittle materials that cannot be threaded. It is installed by inserting the bolt assembly into a hole and then tightening the bolt, which forces the expansion mechanism to press against the walls of the hole.

Examples

• Noun:
  • We used an expansion bolt to securely mount the heavy shelf to the concrete wall.
  • The safety railing was fixed in place with several heavy-duty expansion bolts.
  • For this installation, you will need a drill bit sized specifically for the expansion bolt.

Advanced Usage

• "To set an expansion bolt": The process of installing the bolt by tightening it to cause the sleeve to expand.
  • After drilling the hole, the next step is to set the expansion bolt by turning the nut with a wrench.

Variants and Related Words

• Anchor bolt: A general term for bolts designed to be embedded in concrete, which can include expansion bolts as a subtype.
• Sleeve anchor: A common specific type of expansion bolt where a metal sleeve expands around the bolt.
• Wedge anchor: Another specific type where a wedge is pulled into a sleeve to cause expansion.

Synonyms

• Masonry anchor
• Concrete anchor
• Wall plug (though this often refers to a plastic anchor used with a screw, the function is similar)

Related Phrases

• Expansion bolt assembly: Refers to the complete set of parts (bolt, sleeve, nut, washer).
  • Make sure you have the entire expansion bolt assembly before starting.
• Expansion shield: An older or alternative term for the expandable sleeve part of the assembly.

Noun

1. a bolt that has an attachment that expands as the bolt is driven into a surface