Crane Duty crane duty helical gearbox Helical Equipment Boxes
SELECTION PROCEDURE
Satisfactory performance of the gearbox is dependent upon correct selection. The selection of a gear unit is usually influenced by the course of duty of the crane that ought to be determined and specific. Single, Double and Triple stage Horizontal equipment devices 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 should be specified while purchasing the gear units.
1. Compute the mandatory reduction ratio.
2. Determine the horsepower necessary for the prime mover.
3. Make reference to the rating desk, find in the ratio column and predicated on input rpm examine the gear box ranking horizontally for various class of duty of the crane.
4. The size ought to be selected such that the ranked HP is equal or even more compared to the consumed HP.
EXAMPLE
1. Decide on 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.
· See the ratio column and in the size HB-350, for insight rpm of 720 in course II duty the rated HP is 9.5
· Since the consumed HP is 9, the 
unit HB-350 will be 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.
· See the ratio column and in the size VC – 32Q, for input rpm of 960 in course IV duty the rated HP is 3