Gantry cranes are a type of crane built atop a gantry, which is a structure used to straddle an object or workspace. Gantry cranes for marine application are imposing, multi-story structures prominent at most container terminals, used to load intermodal containers on and off container ships. They can range from these enormous "full" gantry cranes, capable of lifting some of the heaviest loads in the world, to small shop cranes, used for tasks such as lifting automobile engines out of vehicles.
They are also called portal cranes, the "portal" being the empty space straddled by the gantry. The terms gantry crane and overhead crane (or bridge crane) are often used interchangeably, as both types of crane straddle their workload. The usual distinction drawn between the two is that with gantry cranes, the entire structure (including gantry) is usually wheeled (often on rails). By contrast, the supporting structure of an overhead crane is fixed in location, often in the form of the walls or ceiling of a building, to which is attached a movable hoist running overhead along a rail or beam (which may itself move). Further confusing the issue is that gantry cranes may also incorporate a movable beam-mounted hoist in addition to the entire structure being wheeled, and some overhead cranes are suspended from a freestanding gantry.
Full Gantry Crane
Full gantry cranes (where the load remains beneath the gantry structure, supported from a beam) are well suited to lifting massive objects such as ships' engines, as the entire structure can resist the torque created by the load, and counterweights are generally not required. These are often found in shipyards where they are used to move large ship components together for construction. They use a complex system of cables and attachments to support the massive loads undertaken by the full gantry cranes
Rubber Tyred Gantry Crane
Smaller gantry cranes are also available running on rubber tyres so that tracks are not needed. Rubber tyred gantry cranes are essential for moving containers from berths throughout the rest of the yard. For this task they come in large sizes, as pictured to the right, that are used for moving to straddle multiple lanes of rail, road, or container storage. They also are capable of lifting fully loaded containers to great heights. Smaller rubber tyred gantry cranes come in the form of straddle carriers which are used when moving individual containers or vertical stacks of containers.
Portable gantry crane systems, such as rubber tyred gantry cranes, are in high demand in terminals and ports restricted in size and reliant on maximizing vertical space and not needing to haul containers long distances. This is due to the relatively slow speed yet high reach of rubber tyred gantry cranes when compared to other forms of container terminal equipment.
Workstation Gantry Crane
Workstation gantry cranes are used to lift and transport smaller items around a working area in a factory or machine shop. Some workstation gantry cranes are equipped with an enclosed track, while others use an I-beam, or other extruded shapes, for the running surface. Most workstation gantry cranes are intended to be stationary when loaded, and mobile when unloaded. Workstation Gantry Cranes can be outfitted with either a wire rope hoist or a lower capacity chain hoist.
Specifications of Gantry Crane-
Smooth and Noise Less Operation with Testing of 5 to 75 Ton Lifting Capacity Electric Operating Hoists are Centrally Drive Unit and fully tested on Load, Vibrations and Noise at our work and Site for Smooth Operation of Gates from our Quality Control Engineers.