Crane Duty Helical crane duty helical gearbox Equipment Boxes
SELECTION PROCEDURE
Satisfactory performance of the gearbox depends upon correct selection. Selecting a gear unit is influenced by the class of duty of the crane that ought to be determined and specific. Single, Double and Triple stage Horizontal equipment systems type HA, HB and HC are suggested for Hoist and Long Travel drive. Three stage vertical gear models type VC are suggested for cross travel drives of the EOT crane. Assembly arrangement must be specified while purchasing 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 verify the gear box ranking horizontally for various course of duty of the crane.
4. The size ought to be selected such that the rated HP is equal or even more than the consumed HP.

EXAMPLE
1. Select a unit to transmit 9 HP from 720 rpm electric motor for hoist drive in a class II duty crane, the reduction ratio required is 31.50.
· For hoist drive a two stage horizontal gearbox type HB will become suitable.
· 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
· Because the consumed HP is definitely 9, the unit HB-350 will end up being suitable.

2. Decide on a unit to transmit 3 HP from 960 rpm electric engine 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.
· Start to see the ratio column and in the size VC – 32Q, for insight rpm of 960 in class IV duty the ranked HP is 3