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

1. Compute the required reduction ratio.
2. crane duty helical gearbox Determine the horsepower necessary for the prime mover.
3. Refer to the rating desk, discover in the ratio column and based on input rpm check the gear box ranking horizontally for various class of duty of the crane.
4. The size should be selected in a way that the ranked HP is equal or more than 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 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 input rpm of 720 in course II duty the rated HP is 9.5
· Since the consumed HP is usually 9, the machine HB-350 will become suitable.

2. Select 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.
· See the ratio column and in the size VC – 32Q, for input rpm of 960 in class IV duty the rated HP is 3