Hoist Drum Audits

Global’s Aftermarket Replacement Cardan Shaft

Hoist Transmission Cardan Shaft

• Retro-fit to Bucyrus 495HR/HF/HD Models fitted with Series 21 Hoist Transmission.
• Removes the need for accurate motor alignment.
• Allows for floor movement and misalignment up to 5mm.
• Radial loading on transmission and motor bearings is reduced by removing misalignment issues.
• 125kg lighter in weight meaning less inertia, an increase in acceleration / breaking performance and increase the fatigue life of the assembly.
• Designed such that the Fatigue Torque greater than Transmission Stall Torque (49,612Nm).
• Fits the same space envelop as existing OEM coupling shaft.
• Easily serviced, greased, sealed for life joints.

Managing Fatigue Cracking on Haul Trucks

Global’s ACFM program can reduce unnecessary downtime due to fatigue cracking on haul trucks and how it can complement any Reliability Centered Maintenance Program.

Typically maintenance personal generally utilize a preventative maintenance plan which consists of three service levels at varying intervals, with varying maintenance tasks performed at each service level. During this scheduled downtime, the haul trucks undergo routine maintenance procedures such as engine and transmission oil changes. A visual inspection is also made to detect any new cracks, which on any given inspection can number 5 – 10 per haul truck. Of those cracks, between 1 – 3 are generally identified as critical, but will not undergo repairs at this time due to maintenance bay scheduling constraints.

Once a crack has been identified on a haul truck, the maintenance team is currently limited to one of two available options; unscheduled downtime or visual inspection. Each of these options are not only exceedingly expensive, but are often inadequate in their ability to accurately predict critical failure. In addition, each of the above options reduces the mechanical availability of the haul truck.

The solution is to implement a pre-inspection routine concentrating on the critical areas of the truck frame. Using electromagnetic techniques, a pre-inspection can identify and size any fatigue cracking in a very short period of time. Using this method allows planners to schedule the appropriate maintenance personnel to repair critical fatigue cracking during the planned maintenance shutdown.

The prospect of monitoring cracks electronically, without the need for constant visual inspections, was of great value to the preventive maintenance team.