Double Girder Gantry crane is widely used for conveying materials outdoors in mining, seaports, railways and open air storage. It is a kind of bridge crane through the support legs at both sides and beam on the ground. This equipment is made up of trolley, the upper beam, the end beam, the lower beam, supporting legs, driver's room and electric control system and so on.

According to the number of main girder, Gantry crane can be divided into single girder and double girder.

According to the shape of the supporting leg in the plane, Gantry crane can be divided into type A, type U, type C and type L, which type C and type L are belong to single girder gantry crane.

According to the different fetching device, Gantry crane can be divided into hook, grab, or electromagnetic sucker (gantry crane with electromagnet), two or three devices also be used simultaneously.

According to the number of supporting legs, it can be divided into gantry crane and semi-gantry crane. One end of the semi-gantry crane is the supporting leg, which to run on the ground, and the other end is the same mechanism as the bridge crane to run on the track.