25 November 2015, the MD6420C had
accumulated 2518 engine hrs, of
which 1777 were drill hrs; 4354 holes
were drilled at an average hole depth
of 14.6 m (48 ft). This MD6420C is
configured with a Cat C27 Tier 2
engine operating at 1800 RPM
(previous drills were 2100 RPM),
powering a 2000 ft
3
/min.
low‑pressure compressor with
electronic control interface.
All of the rigs at this site are drilling
the same hole diameter, depth and
drill patterns. The average load factors
and corresponding fuel consumption
improved significantly because of the
electronic controls that unload the
compressor when not in drill mode
and the auto-functions that ensure
smooth and consistent operation,
while levelling and while drilling.
New technologies join
solid structures
The original MD6420 was a simple
design configured with hydraulic
pilot controls, point-to-point wiring
and a pneumatic compressor
regulation package. The solid design
concept combines with heavy-duty
structures and high-performance
components. The latest model
includes structural improvements and
upgrades to the main frame, A-frame
and mast. Plus, the MD6420C is
equipped with a proven Cat engine
and durable Cat undercarriage.
The new MD6420C incorporates
cutting-edge technology in its
controls, monitoring system and
computer interface. Drillers
specifically compliment the drill
functions, touchscreen, gauges,
controls and cab layout.
When the MD6420C drill first went
into production, the mine only
allowed the most experienced drillers
to run the rig. After they gained
familiarity with the controls and
drilling screens, they quickly
appreciated the ease of operation and
production improvements.
Eventually mine management
allowed the use of the MD6420C to all
drillers as a training tool. New drillers
sat in the trainer’s seat and observed
an experienced driller use the
touchscreen, the auto drilling
functions and occasional manual
drilling to demonstrate key elements.
The new drillers watched the
machine navigate through
auto-levelling, auto-mast-raise-and-lock,
and single pass auto drill. The new
drillers learned, while the system
modulated pulldown, water injection
flow rates, rotary torque and RPM,
while drilling through various strata
and ground conditions.
Adapting to new drilling
methods
Experience at this site, and many
others in the Americas, Australia and
Africa, show that different drillers
approach these kinds of
Drill communicates and automates
The Cat MD6420C features a graphical user interface to provide accurate,
concise data and feedback to the operator, which in turn helps improve
productivity and reduce rework costs. Operator data encompasses both drill
health and drill performance. The general layout of the drilling, levelling and
tramming screens easily guides the driller through the processes and functions.
The machine’s onboard processor and CAN Bus design tracks component
status, interlock conditions and other related inputs thousands of times a
minute. Operators are kept informed of machine condition through display
messages, colour codes and symbols.
The MD6420C main functions are completely automated and require only
the touch of a button for each: auto-level, auto-mast raise and lock/unlock
and lower, and single-pass auto-drilling.
The MD6420C also has a full set of manual controls integrated with the
electronic control module (ECM) that allow for smooth and easy tramming,
levelling and drilling. The A-frame design includes multi-stage mast raise
cylinders, integrated mast locking system and a closed loop pulldown circuit
for stability when tramming and drilling.
Drill operators report key performance improvements when comparing the
new generation machine, to its peers, including:
n
n
Lower fuel consumption than the older generation drills.
n
n
Longer bit life.
n
n
More drill footage and consistent hole quality.
The MD6420C drill control system provides a solid base for autonomous operation.
June 2016
|
World Coal
|
41
