Spotlight Feature Articles Joy Global Drilling & Loading Apr17 | Page 4

DRILLING AND LOADING
new projects in the pipeline and remain focussed
on optimising drills in the mining process,
increasing safety and lowering TCO.”
Latest on FLANDERS FREEDOM
automation
ARDVARC ® is the drill control system from
FLANDERS Inc that is compatible with all OEM
rotary drills. The company states that it is one of
the few systems that allows for complete
automation, as opposed to remote control, of the
drilling process. After positioning the drill
manually or autonomously over the collar using
precision GPS, the ARDVARC system levels the
machine; collars the hole; drills to the desired
bottom-hole elevation; retracts the drill string;
and resets the jacks in preparation for moving to
the next hole.
ARDVARC has been successfully installed on
over 60 drills worldwide and has drilled millions
of blast holes in the last ten years. It has
provided measured improvement in overall
operating costs in coal, copper, iron, platinum,
and gold open pit operations. The system was
covered in detail in an award winning ISEE paper
from January 2017 by Eric Gerst, FLANDERS
Global Business Development Specialist, Drill
Automation.
Of the available FREEDOM platforms, One-
Touch is the most popular option. It requires a
driller be on board the machine but controls the
entire drill sequence. Drill hole parameters are
entered into the system wirelessly and once the
driller positions the machine over the hole collar
the drilling sequence is started at the touch of a
button on the HMI screen or purpose built
operator’s chair. “ARDVARC offers the only true
automated drilling process in the world today.
The unique Dynamic Hole Quality Algorithm
monitors the drill performance and dynamically
adjusts rotation, down pressure, and air
pressure each foot of hole drilled to maximise
penetration rates, according to geologic
conditions.”
The Dynamic Hole Quality Algorithm also
clears stuck or clogged bits, finishes the hole,
and frees hung drill strings during retraction
without intervention from the operator. In
addition, each power system on the drill is kept
below OEM operating maximums to prevent
overextending the drill’s capabilities and causing
damage or premature wear to the machine and
ground engaging tools. Fully Autonomous utilises
the same Dynamic Hole Quality Algorithm as
One-Touch but allows one operator to run up to
four drills from a remote Command Centre. Unlike
remote control that requires full operator
intervention for each drill, ARDVARC Fully
Autonomous allows the drill operator to enter a
drilling plan into the system to include hole collar
coordinates, the order in which the holes are
International Mining | APRIL 2017
drilled, and bottom hole elevation. The drill will
execute the plan without operator intervention.
Haz-Cam Object Detection technology prevents
collisions with persons or equipment working in
the area and disables the drill if the hazard zone
is breached.
Finally, the Multi-Pass Option allows for the
semi-autonomous changing of steels. It is
available for One-Touch and Fully Autonomous.
Once the end of a steel is reached, ARDVARC runs
a step-by-step process of the assembly or
breakdown of additional drill steel.
Machine Health Data collected by ARDVARC
shows information on 28 monitored systems on
the drill.
The paper also included a case study from an
open pit iron ore mine that produces
approximately 44.9 Mt of ore annually with a
stripping ratio of 3.5 t of waste per tonne of ore.
The dominant ore body is haematite with a
specific gravity of 3.25 g/cc and compressive
strength of 40,000 psi.
The mine drills a 9 7/8” hole on a typical 20 x
21 pattern to a bench height of 41 ft. Their drill
fleet consists of six diesel powered Cat 6420C
machines. Automation of their drill fleet began in
June 2015 with the installation of a One-Touch
style system on one drill to test the efficacy of
the technology. Two more drills were added in
August 2015, one in September 2015, and the
final two in November 2015. The mine is in the
process of implementing fully autonomous
drilling for the entire fleet.
The percentage of holes drilled using
automation has increased over time as operators
are trained and gain confidence in the
technology. By the end of the study period, 85%
of the holes were drilled using automation.
Productivity is an average measure of various
efficiencies whose inputs include mechanical
availability and the actual drilling activities of the
machine. The mechanical availability of this fleet
was between 85% and 90% through the last few
months of study data. The individual drilling
activities analysed were:
a) Drill Accuracy – Planned Hole Location X, Y,
and Z versus Actual Drilled Location
b) Penetration Rate
c) Drill Metres per Month
d) Number of Holes Drilled Per Month
e) Drill Productivity
f ) Tonnage and Feet Drilled Plan vs. Actual
“Probably one of the more interesting
changes in drilling activity using automation is
how the entire fleet’s performance becomes uniform
with very little variation. This offers tremendous
advantages in planning and forecasting.”
Accuracy of drill hole placement is measured
on three planes – X axis (burden), Y axis
(spacing), and Z axis (bottom hole
elevation/depth). At this operation, surveyors
mark the collar locations prior to drilling. The
drillers tram the machine using a targeting device
on their One Touch System to align the drill over
the hole. When the drill bit contacts the ground
the system records the elevation and coordinates
of the collar. Comparing the surveyed coordinates
pre-drilling and the actual drilled coordinates
illustrates drilling accuracy.
Prior to automation of the fleet anywhere from
10% to as high as 30% of the holes were “out of
spec” – meaning off by at least one hole
diameter in one or all of the three planes. The
introduction of automation saw more than 90%
of the holes being on plan in the last three
months of the study period.
Hole to hole penetration rates show the metres
drilled/hole over the drill cycle time. The drill
cycle time includes time to tram to the hole
collar, level the drill, collaring the hole, drilling
the hole, retracting the drill str