Gantry girders are used to provide support for overhead traveling cranes in environments such as warehouses and construction workshops, according to The Constructor. Gantry girder cranes are used in these environments to move heavy equipment and supplies around the work area by means of a hand-operated or electronically controlled crane.
A gantry girder is the piece of a crane that contains the equipment allowing the crane to roll over during its operation. The girder is designed to support the crane and the loads inflicted on the crane throughout its life. A gantry girder is supported by columns, with little or no support between the columns to avert the twisting and bending of the girder metal. Supports are often only provided over the span of a crane where a walkway is included in the crane design. To support a gantry girder, civil engineers design support columns as either stepped columns or central columns -- depending on the loads the crane will move.
Gantry girders are used in the construction of cranes for use in manufacturing facilities -- such as shipbuilding yards, where large equipment and materials are used, according to EMH Cranes. In power plants, gantry girders are used on cranes that act as hoists for the movement of equipment during installation and maintenance procedures. Industrial applications include the installation of gantry girders for use in facilities that include steel production plants.
Gantry girders are used to provide support for cranes because of the various directions loads are exerted on the cranes during the moving process for loads. Movement of heavy loads via girder cranes exerts vertical and horizontal loads on the gantry girder, with the vertical load applied to the girder by the crane itself. Horizontal movement is exerted on the gantry girder by the surge, or acceleration and braking of the crane operation, and the swinging of loads throughout the movement of loads.
The operation of gantry cranes using girders for strength and stability is completed by an operator in a covered or uncovered cab. Covered cabs are often used in applications open to weather changes and dangerous environments. The gantry girder is attached to a bridge that spans the area the crane is operated over, The Constructor reports. The operating cab is located close to the bridge to provide the operator a full view of the operating area. The crane is attached to rollers that roll over the gantry girder, allowing the crane to move goods around the area.