A roller circle assessment (center of gravity test + roller load test + spall test) was conducted on a Marion Dragline to determine the center of gravity, the remaining useful life of the roller circle components, and the best way to extend the existing component lives without a wholesale component replacement.
The center of gravity test identified the machine was under ballasted, and the recommended weight of ballast to add.
The roller load test identified the lead-in rails on the revolving frame had improper tapers, the exact locations where geometry issues existed in the revolving frame rail pad, and where machine loads were concentrated around the rail gaps. Procedures to remove these load concentrations, and reduce the high roller forces and stresses were provided.
The spall test identified which rails had spalling and their detailed location, depth and severity. Actionable solutions were provided to double the remaining useful roller circle component life, using the existing components.
