What was the design methodology for the portal conversion?
We selected a target vehicle weight (6000 lbs), engine torque (500 ft-lb), gearing and tire size to guide the design of the case, gearing, and attachment knuckles. Target life for gears and bearings is 10,000 hours before failure. Target loading for the wheel end follows our normal combat vehicle design guidelines of 5g (5 times normal axle loading – 1g static + 4g dynamic). Target vehicle speeds ranged from crawl speed up a 60% grade to 80 mph. Finite element analysis (ABAQUS software) and gearing/bearing performance simulation (ROMAX software) were used extensively throughout the design process. Our overriding concern was an easy interface to the axle. We retained the standard Dana 60 yoke / u-joint and kingpin mounting interfaces. This approach allows you to take advantage of existing upgrades that have been developed over time.
