Dam top gantry crane can be divided into two kinds: unidirectional crane and bidirectional crane. The unidirectional hoist is fixed on the gantry frame. The Gantry runs along the track on the dam. And its service zone is a line, which can only be used to lift a gate of the same row, while the double direction gantry crane is with a trolley running perpendicular to the crane traveling. Thus, the double direction gantry crane can lift the floodgate or trash racks of different rows of upstream side and the downstream side.

There are two kinds of dam top gantry crane: 1. Single direction: The lifting mechanism (slings/hook) is fixed on trolley and only travel along the rails direction on main beams, thus it can only lift one side floodgate/trash rack. 2. Double directions: The lifting mechanism on trolley can move vertically against the main beam rails direction, thus it can be used to lift 2 sides’ floodgates/trash racks of upstream and downstream.

Features: 

1. Steel plate or box-type girder, electric driving motor of lifting mechanism, gear reducing hoist;

2. The operating mechanism of the crane is driven by the motor, and the closed operating room is mounted on the frame;

3. Running buffer device and windproof rail clamp are equipped under the gantry leg;

4. The spreader moves up and down along the gate slot or around the hinge of the gate;

5. The opening and closing of the gate in the movable water is related to the size of the load and the water hydrodynamic pressure.

The dam top floodgate gantry crane is mainly used for hydraulic equipment transport, installation and maintenance of hydroelectric generating units such as floodgates, trash rack etc.

In terms of hydraulic equipment transport, the crane plays a crucial role in moving large - scale floodgate components. These components, often fabricated at remote locations, need to be precisely transported to the dam site. The gantry crane's large - span structure and high - capacity lifting mechanism enable it to hoist and transfer the heavy floodgate segments along the dam top, ensuring a smooth and safe journey from the storage area to the installation position. For trash racks, which are essential for filtering debris from water intake systems, the crane can efficiently transport the pre - assembled racks to their designated spots near the water inlets.

During the installation of hydroelectric generating units, the dam top floodgate gantry crane is indispensable. When it comes to floodgate installation, the crane precisely positions each floodgate section into the pre - constructed slots. Its high - precision control system allows for millimeter - level adjustments, ensuring a tight seal between the floodgates and the dam structure. This is crucial for the proper functioning of the flood control system. For trash rack installation, the crane carefully lowers the racks into place, aligning them with the water intake channels to optimize water flow while effectively blocking debris.