The casting bridge crane is the main lifting and transportation equipment in the steel smelting workshop, used for the transportation, pouring, and mixing of liquid metal during the smelting process. Below 125t, it is generally a YZ type double beam structure. 125t and above are generally YZS type four beam structures. The YZS model adopts a main and auxiliary double trolley, four beam and four track structure, mainly composed of a bridge, main trolley, auxiliary trolley, hook beam, crane operation and electrical parts. The main trolley runs on the main beam track on the outer side of the bridge, and the auxiliary trolley runs on the auxiliary beam track on the inner side of the bridge. The main trolley lifting device is a fixed spacing hook beam.