Crane Duty Helical Equipment Boxes
SELECTION PROCEDURE
Satisfactory performance of the gearbox depends upon correct selection. Selecting a gear unit can be influenced by the course of duty of the crane that ought to be determined and specified. Single, Dual and Triple stage Horizontal equipment products type HA, HB and HC are crane duty helical gearbox 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 should 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 table, observe in the ratio column and predicated on input rpm examine the gear box rating horizontally for various course of duty of the crane.
4. The size ought to be selected such that the ranked HP is equal or more compared to the consumed HP.

EXAMPLE
1. Decide on a unit to transmit 9 HP from 720 rpm electric motor for hoist drive in a course II duty crane, the reduction ratio required is 31.50.
· For hoist drive a two stage horizontal gearbox type HB will become suitable.
· Start to see the ratio column and in the size HB-350, for input rpm of 720 in course II duty the rated HP is 9.5
· Because the consumed HP is 9, the machine HB-350 will end up being suitable.

2. Select a unit to transmit 3 HP from 960 rpm electric electric motor for cross travel drive in a course IV duty crane, the reduction 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 input rpm of 960 in class IV duty the ranked HP is 3