No. 1 Chain Breaker Suits 25 to 60 ASA & BS Pitch Chain

A chain breaker — also sold as a chain puller — is a hand tool that presses a roller chain's connecting pin out to disconnect the chain at any link, or presses a pin back in to rejoin it, without needing a connecting (master) link at that point. It's the standard way of shortening roller chain to the exact number of pitches a drive calls for, and of breaking a worn chain out during replacement.

Pitch Range

This No.1 chain breaker suits ASA 25 to 60 pitch (BS 06B to 12B) — light-to-medium chain, covering the common conveyor and agricultural drive sizes. For larger chain, see our No.2 Chain Breaker (ASA 60 to 100 / BS 12B to 20B), or contact the AIMS team for chain outside either range.

Using This Tool

Check how your chain is riveted before starting: centre-sink riveted chain can go straight onto the tool with no preparation, while double or quad-stake riveted chain needs the rivet heads ground back with an angle grinder first. The tool must be firmly secured — bench-mounted or clamped over solid support — before applying pressure, and safety glasses should be worn.

For the full how-to, including common mistakes and rejoining with a connecting link, see our Chain Breaker Guide.