Rational structure is of box construction (As per IS - 800 Bridge Girder structural calculation) adequately designed and reinforced by stiffening ribs. It is connected with bridge trolley, which is moved by motors, coupled up with speed reducers. The crab carriage is in steel section. It comprises of special crane duty motor, connected to speed reducers and is coupled to a grooved steel drum. Electromagnetic brakes are used to control the smooth lifting of weight. AC drive is also provided (on demand) for smooth operation of long travel.
The hook is equipped with a forged steel forked revolving hook. Wire Rope is of 6 x 37 construction. Electric operations are controlled with push button control unit independent from the position of Winch Trolley and sliding in loop through cable carriers. Limit switches are provided for all operations, to ensure accident free operations.