Bridge cranes

An overhead crane, commonly called a bridge crane, is a type of crane found in industrial environments. An overhead crane consists of two parallel rails seated on longitudinal I-beams attached to opposite steel columns by means of brackets. The traveling bridge spans the gap. A hoist, the lifting component of a crane, travels along the bridge. If the bridge is rigidly supported on two or more legs running on two fixed rails at ground level, the crane is called a gantry crane (USA, ASME B30 series) or a goliath crane (UK, BS 466). Another variant is the semi-goliath crane, where one fixed rail is at ground level, and the other fixed rail is overhead, commonly used along the exterior of an existing building. Unlike mobile or construction cranes, overhead cranes are typically used for either manufacturing or maintenance applications, where efficiency or downtime are critical factors.