Open Cut » Maintenance & Equipment
Tyre handling is a major source of risk in surface mining operations, and in an incident in 2018, a fatality occurred when a tyre slipped from the grip of a tyre handling machine whilst being washed down.
Project C29043 designed, developed and commissioned a tyre handler gripper friction test rig to enable the frictional force between gripper and tyre to be quantified for a range of tyre types, pressures, tyre tread and sidewall wear modes, and surface wetting conditions.
This project covers the next phase of test work made possible by the fully commissioned test rig. The aim being to scientifically address the industry wide knowledge gap around how operation and tyre parameters effect tyre handler gripper/tyre traction performance.
The project's objectives were to:
- Quantify the maximum lift force for various pad-to-tyre contact conditions;
- Identify the critical parameters that influence Factor of Safety (FoS);
- Provide observations for improvement in tyre handling operations.
Observations in the following areas are fully described in the final report:
- Slip mechanism;
- Tyre wear;
- Tyre orientation;
- Tread wetting;
- Vertical tyre handling;
- Horizontal tyre handling.
From the perspective of minimising potential pressure energy release, it is desirable to handle tyres at the lowest pressure that will ensure adequate handling. This must ensure that there is no bead-seat displacement when lifting tyres, which is more likely to occur when lifting a tyre from the horizontal position due to shear forces prevailing on the bead seat.