These gates are used to control the flow of water in a river. The gate structure incorporates a torque tube along the bottom edge which transfers the water load through to the actuator, this is normally a hydraulic cylinder.
Advantages
The gate installation is unobtrusive.
Torsion tube allows operation from one side.
Good overflow discharge characteristics.
Disadvantages
Limited to short spans due to gate deflection.
The actuator is located in a pit alongside the water channel and passes through a seal in the side wall giving additional civil costs.