Gantry crane

A gantry crane is a lifting machine whose hoist trolley runs along a horizontal beam carried on legs that travel on rails or wheels, spanning the load rather than rotating over it like a jib crane. At a port the family covers the rail-mounted ship-to-shore (STS) quay crane, the rail-mounted gantry (RMG) and automated stacking crane (ASC) in the yard, and the rubber-tyred gantry (RTG) over wheeled lanes. Gantry geometry gives a large clear working envelope and high wheel loads concentrated on the rails or runway, which drive the quay and pavement design. The container variants lift through a spreader engaging the corner castings, the bulk variants through a grab or a fixed shiploader boom.