singlegirder

Singlegirder is a type of overhead crane used in industrial settings to move loads within a workshop or warehouse. It features a single bridge girder spanning between two end trucks, on which a hoist and trolley travel. The hoist is mounted on the trolley and can move along the length of the bridge; the end trucks ride on runway rails fixed to supporting beams or columns.

Two common configurations exist: top-running, where the hoist travels above the bridge girder on a trolley; and under-running (or under-slung), where the hoist and trolley are supported from below by the bridge. Top-running cranes are typical for larger clearances and heavier hoists, while under-running cranes save headroom in low-ceiling environments.

Singlegirder cranes are generally lighter and less expensive than double-girder designs and are suitable for light- to medium-duty loads and moderate spans. Typical rated loads range from a few tons up to around 20–25 tons, with spans often in the range of 6 to 25 meters, depending on design. Maintenance is simpler, but deflection under load can be greater than in double-girder configurations; the choice of girder section (I-section or box) and end-truck design affects wheel loads and runway performance.

Applications include manufacturing lines, automotive plants, metal fabrication shops, and general warehousing where space is limited or a lighter crane suffices. Design and installation follow national and international standards to ensure safety and compatibility with hoists and end-trucks.