Crane Duty Helical Gear Boxes
SELECTION crane duty helical gearbox PROCEDURE
Satisfactory performance of the gearbox is dependent upon correct selection. The selection of a gear unit is influenced by the class of duty of the crane that ought to be determined and specified. Single, Double and Triple stage Horizontal gear products type HA, HB and HC are recommended for Hoist and Long Travel drive. Three stage vertical gear models type VC are recommended for cross travel drives of the EOT crane. Assembly arrangement should be specified while buying the gear units.

1. Compute the mandatory reduction ratio.
2. Determine the horsepower required for the prime mover.
3. Refer to the rating desk, find in the ratio column and predicated on input rpm verify the gear box rating horizontally for various course 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 reduction 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 course II duty the ranked HP is 9.5
· Because the consumed HP is 9, the machine HB-350 will end up being suitable.

2. Decide on 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 become suitable.
· Start to see the ratio column and in the size VC – 32Q, for input rpm of 960 in class IV duty the rated HP is 3