To solve the problem, the company standardized its pilers and processing plants on one suite of gear drives from Rexnord Corp., Milwaukee.
In the conveyors’ planetary gear drives, Rex tapered roller bearings support overhung and thrust loads on both input and output shafts. Spline connections isolate the gear train from external forces. Taconite duty-rated seals and two seals on each shaft sport greasepurgeable cavities that keep out dirt and moisture. An internal backstop ensures safety for the incline conveyor. When required, the drive’s standard subassemblies allow fast gear ratio changes in the field without shimming bearing clearances, bearing adjustments, or even special tools.
Falk Ultramite gearmotors drive the tracks that move the pilers, stacker boom swing, and hoist. The gearmotors’ generate low speed directly, which is important because previous multireducer drives were prone to ill-timed failures. Gearbox bearings, not motor bearings, support a built-in high-speed pinion. The gearbox accepts standard NEMA C-face motors, so they are easy to remove and replace.