Most of the draglines currently operating in Australia were supplied with OEM designed access systems (walkways, platforms, stairs etc) that do not comply with Australian design codes. Safety reviews combined with high maintenance costs, due to fatigue cracking, have lead to mining companies seeking design solutions that are AS 1657 compliant. CMP Engineers has designed access systems (walkways, platforms, stairs etc) for BE 1370W and Marion 8050 draglines which incorporate a number of innovative features.
Tri-axial accelerometers have been used to measure the loading on the supports connecting the access systems to the dragline structures (boom, mast etc) and an equivalent fatigue load calculated. Using these loads the supports and access system has been designed for a 25 year life, using finite element analysis to calculate the stresses.