LEXICONMachine components
Demolition grapple
Also called: Sorting grab, demolition grab, orange peel grab
A hydraulically operated pair of toothed jaws mounted on an excavator arm, used to grip, sort and load irregular material — demolition rubble, scrap, timber — that a bucket cannot hold.
What it does
Where a bucket scoops, a grapple grips. Two or more jaws close under hydraulic pressure with enough force to crush masonry and hold a steel section securely while the machine swings. Most rotate continuously so the operator can align the jaws with whatever is being picked up. Sorting grabs used in recycling have flatter jaws and closer tines; demolition grabs are heavier, with fewer, thicker teeth designed to survive impact against concrete and reinforcement.
Why it becomes an object
A grapple jaw is a shape entirely determined by force: a curved plate with the section deepest where the pivot loads it, teeth at the working edge, and gussets where the cylinder pushes. In use it closes on itself, so the two jaws are mirrored halves of a single form, and the wear appears where they meet. Retirement is usually a cracked jaw or a worn pivot bore. The surviving jaws read as an opened shell — a form with an obvious inside and outside, which is unusual in salvaged steel.
