Crane Duty Helical Equipment Boxes
SELECTION PROCEDURE
Satisfactory performance of the gearbox depends upon correct selection. Selecting a gear unit is usually influenced by the class of duty of the crane that ought to be determined and specific. Single, Double and Triple stage Horizontal gear units type HA, HB and HC are recommended for Hoist and Long Travel drive. Three stage vertical equipment products type VC are recommended for cross travel drives of the EOT crane. Assembly arrangement must be specified while 
ordering the gear units.
1. Compute the required reduction ratio.
2. Determine the horsepower necessary for the prime mover.
3. Refer to the rating desk, discover in the ratio column and predicated on input rpm crane duty helical gearbox verify the gear box rating horizontally for various class of duty of the crane.
4. The size ought to be selected in a way that the ranked HP is equal or more than the consumed HP.
EXAMPLE
1. Select a unit to transmit 9 HP from 720 rpm electric electric motor for hoist drive in a class II duty crane, the decrease ratio required is 31.50.
· For hoist drive a two stage horizontal gearbox type HB will end up being suitable.
· Start to see the ratio column and in the size HB-350, for insight rpm of 720 in class II duty the ranked HP is 9.5
· Since the consumed HP is usually 9, the machine HB-350 will be suitable.
2. Select a unit to transmit 3 HP from 960 rpm electric motor for cross travel drive in a course IV duty crane, the decrease ratio required is 14.26.
· For cross travel drive, a vertical gearbox type VC will end up being suitable.
· See the ratio column and in the size VC – 32Q, for insight rpm of 960 in class IV duty the ranked HP is 3