- Annal A 3 1 Helical Reduction Gearbox Is Required To Drive A Roller Chain Transmission On A High Speed Hoist The Helic 1 (115.44 KiB) Viewed 11 times
AnnAL. A 3:1 helical reduction gearbox is required to drive a roller chain transmission on a high speed hoist. The helical gearbox is in turn driven by a 50 KW AC Induction motor, via a V-Belt system as illustrated in the diagram above. The helical gears are machined with a 20° normal pressure angle and a 30° helix angle. The pinion has 15 teeth and a normal module of 5.5 mm. The pinion is made from En24(U) alloy steel, 302 BHN and the gear from En9(5), 277 BHN. A contact ratio of 1.3 exists between the gear and pinion. The pinion will experience 50% chance of failure after 1700 hours of operation. The following series of questions will be used to determine the ideal face width of the gear and pinion to ensure the satisfactory operation of the gearbox. Base your final answer on the surface endurance strength and surface fatigue strength of the pinion. Assume no reserve factor.