WINNING
to prevent undulations developing. The
material should, however, not become
too moist when wet, to the extent where
wheels sink into the haul road, bringing
the sidewalls of the tyre in contact with dirt
and wear away the rubber. If there is high
rolling resistance on the haul road, the tyres
are not biting into the road and in effect are
burning rubber off the tyre.
Dust control is also required as part of the
environmental management plan at quarries
and usually entails regular grading and
spraying or wetting of the haul road surface.
Main causes of tyre damage
Vista Training, a US-based company, has
identified the main causes of quarry vehicle
tyre damage. The most common cause is
sidewall damage leading to tyre failure. This
happens when trucks and earthmoving
equipment gets too close to berms and high
bank faces, normally on narrow haul roads
where trucks operators steer to the outside
edge of the road to pass trucks coming from
the opposite direction.
Drivers should avoid hazardous surfaces to ensure all tyres remain in working order.
“The most common
cause is sidewall
damage leading to
tyre failure.”
Hazards associated with loading includes delivering material to the plant where backing up over
a stockpile or other material can cause severe damage to tyres.
Corners are another area where tyres
can run over berms. Other hazards are
associated with loading at a shovel or
tipping point and can include backing up
over spilled material or backing up too far
until the truck's rear duals are resting upon
the edge of the pit face.
Running a tyre on a rutted road is
identified as another hazard as it can cut the
sidewall and put stress on the carcass when
entering and leaving the rut. A rut will cause
the tyre to wear unevenly due to surface
variations. Vehicle operators should be
encouraged to use different areas within the
haul lane to avoid ruts as much as possible.
Underinflated tyres experience significant
sidewall deflection, especially when the
truck is travelling with a load. The result is
The design of bench and dump areas can increase tyre life and reduce spillage. The turn
should be broad enough to enable to turn the equipment quickly without dry steering on
loose material.
QUARRY SA | MAY/JUNE 2018 _ 17