Crane Duty Helical Gear Boxes
SELECTION PROCEDURE
Satisfactory performance of the gearbox depends upon correct selection. The selection of a gear unit is usually influenced by the class of duty of the crane which should be determined and specified. crane duty helical gearbox Single, Double and Triple stage Horizontal equipment models type HA, HB and HC are recommended for Hoist and Long Travel drive. Three stage vertical equipment models type VC are recommended for cross travel drives of the EOT crane. Assembly arrangement must be specified while buying the gear units.
1. Compute the mandatory reduction ratio.
2. Determine the horsepower required for the prime mover.
3. Make reference to the rating desk, see in the ratio column and based on input rpm check the gear box ranking 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 engine for hoist drive in a course II duty crane, the decrease ratio required is 31.50.
· For hoist drive a two stage horizontal gearbox type HB will be suitable.
· See the ratio column and in the size HB-350, for input rpm of 720 in course II duty the ranked HP is 9.5
· As the consumed HP is 
definitely 9, the machine HB-350 will be suitable.
2. Decide on a unit to transmit 3 HP from 960 rpm electric motor for cross travel drive in a class IV duty crane, the reduction ratio required is 14.26.
· For cross travel drive, a vertical gearbox type VC will become 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