FOUR GIRDER EOT CRANE
FG EOT crane is a type of electric overhead travelling crane in which there are four nos. girders. A pair of girders is called main girders and other pair of girders is called auxiliary girders.
FG EOT crane have two nos. trolleys/ crabs. One trolley is mounted on main girders and other trolley is mounted on auxiliary girders. The two trolleys move one below the other.
FG EOT cranes are generally used for hot metal handling purpose.
Bridge/ GirderBridges consist of double web box type structural construction on which the trolleys move. Long travel drive assembly is provided on either sides of the bridge for movement of the crane on the gantry rails.
Trolley/ CrabTrolleys consist of structural frame on which hoist mechanism and cross travel mechanism of crane are mounted. The hoist mechanism is used to lift the load. The cross travel mechanism is used to move the lifted load across the span of crane. The upper trolley is bigger trolley and lower trolley is smaller trolley.
Four Girder EOT Crane
Hoist MechanismThe Hoist Mechanism consists of assembly of motor, gearbox, brake, coupling, drum, wire rope and hook block. The hook block consists of sheave assembly which supports a swivel hook. The hook block is suspended from drum through wire rope. The wire rope is wound on grooved drum which is long enough to accommodate the length of rope required for the specified lift. Selection of wire rope size is dependent upon load to be lifted and the number of rope falls. Depending upon rope reeving arrangement either rope balancer or equiliser sheave may be provided on the trolley frame. The hoist drum is driven through motor- brake- gearbox- coupling arrangement.
As a safety feature Gravity Limit Switch & Rotary Limit Switch are provided for hoist motion.
Cross Travel MechanismThe Cross Travel Mechanism consists of assembly of motor- brake- coupling- gearbox - wheel. The cross travel wheel runs on rails installed on the bridge/ girder of the crane.
As a safety feature two way lever operated Limit Switch is provided for CT motion. Also spring buffers are provided at the four corners of the trolley for safety purpose.
Long Travel MechanismThe Long Travel Mechanism consists of assembly of motor- brake- coupling- gearbox - wheel. The LT wheel runs on rails provided on the gantry. Crane wheels are generally double flanged. However Flange-less wheels with guide rollers are also used.
For safety purpose spring or hydraulic buffers are provided at the four corners of the bridge of crane. Also a two way lever operated Limit Switch is provided for LT motion.
The crane is operated from either operator cabin installed below the bridge or radio remote control of the crane.