A Gantry / Goliath crane is a type of overhead crane with a single or double girder configuration supported by freestanding legs that move
on wheels or along a track or rail system. Gantry cranes are usually considered when there is a reason not to incorporate an overhead
These are typically used for an outdoor application or below an existing overhead bridge crane system . Unlike a bridge crane, a gantry crane does not need to be tied into a building's support structure eliminating the need for permanent runway beams and support columns. In some cases, this can result in a significant reduction in material costs and can be a more cost-effective solution compared to a similarly specified bridge crane.
Larger gantry systems may run on a rail or track embedded in the ground, typically in a straight line in a dedicated work area. Smaller portable gantry systems run on castors or wheels and can be moved about a facility for maintenance or light fabrication work.