Gantry Cranes

These are sometimes called portal cranes and consist basically of two `A' frames joined together with a cross member on which transverses the lifting appliance. In small gantry cranes (up to 10 tonnes lifting capacity) the `A' frames are usually wheel mounted and manually propelled whereas in the large gantry cranes (up to 100 tonnes lifting capacity) the `A' frames are mounted on powered bogies running on rail tracks with the driving cab and lifting gear mounted on the cross beam or gantry. Small gantry cranes are used primarily for loading and unloading activities in stock yards whereas the medium and large gantry cranes are used to straddle the work area such as in power station construction or in repetitive low to medium rise developments. All gantry cranes have the advantage of three direction movement

1 . Transverse by moving along the cross beam.
2. Vertical by raising and lowering the hoist block.
3. Horizontal by forward and reverse movements of the whole gantry crane.