DRILLING AND LOADING
Depending on the specific digging practices
followed in the mine, the Operator Assist –
Enhanced Motion Control system can yield a
number of significant benefits, including more
reliable crowd rope replacement schedules, full
design life for hoist ropes, reduced wear on
crowd brakes, and longer life for hoist gear case
components. By intelligently controlling machine
motions under certain conditions, the system
reduces downtime for maintenance and repair.
This translates to added production and lower
cost per tonne, with a return on investment
typically less than six months according to
Caterpillar.
When developing the system, Caterpillar
engineers reviewed the operating habits of
numerous operators of all skill levels. Based on
this practical information, the new system
addresses specific operating situations that
could potentially jeopardise both the machine
and the production schedule.
Over-crowding the dipper and excessive
loading can stall the dipper and place
detrimental forces on hoist gear-case
components. The system monitors force and
optimises crowd/retract commands in relation to
hoist speed. Optimising the loading cycle
reduces stress and wear on hoist system
components.
The Operator Assist—Enhanced Motion
Control system is available for three 7495
machine classes: 7495 (ER601143
& up); 7495 HF (ER801136 & up);
and 7495 HD (ER701167 & up).
The control system software
update typically requires only two
hours.
The Cat ® LatchFree™ Dipper
System is the first successful
solution to the most common
cause of rope shovel downtime.
The system replaces the standard
maintenance-intensive latch
assembly with a strong steel link
assembly mounted to the dipper
back. The key to the design is the
geometry of the locking
mechanism. The unique
arrangement makes it possible to
locate the components away from the harsh flow
of material.
“The system has been designed and field
proven for a service interval of 3,000 hours, as
compared to the standard system that requires
adjustment as often as each shift. In addition to
delivering greater uptime and lower maintenance
costs, the system eliminates false trips –
releasing the dipper door inadvertently – caused
by dirt buildup or the need for adjusting shims.
The result is fewer delays, consistent production
and lower cost per tonne.”
The LatchFree Dipper System is currently
Cat LatchFree Dipper on 7495 shovel
available for Cat Electric Rope Shovels with
dipper capacities of 45 m 3 or smaller. The system
proved its performance on a Cat 7495 loading Cat
797 trucks in the challenging oil sands of Alberta,
Canada.
“We’re giving it the best challenge – with the
environment along with the volumes we mine
every day – to test this product to the limit,” said
Dino Colbourne, Maintenance Manager of Shell
Albian Sands, during field testing of the
LatchFree Dipper System.