Dragline capacity assessments


  • Current safe capacity of the dragline structure unknown
  • No design standard for design in public domain - loading undefined
  • Forcing functions significantly changed by digital control systems
  • Ageing structures & increased duty with time


  • Based on leading edge reliability engineering principles
  • Force spectra defined by instrumentation and testing
  • FEA & structural design compliance to AISC & BS 7608
  • Recommendations for member upgrades for operating at higher mean RSL levels within a safe working envelope
  • Dragline capacity & components life assessment of key mechanical components and electrical motors for operating at higher mean RSL levels
  • Optimal bucket sizing for maximizing production and reliability


  • Dragline capacity assessments completed on 65 draglines for BHPB (Australia, USA & SA), RioTinto, Anglo, Xstrata, Peabody (USA)
  • Draglines operating at 115%RSL to 125%RSL within safe working envelope after up grades
  • Upgrades recommended for improved reliability