Page 24 - CEN 13 Apr.indd

22
APRIL 2013
mining
The Joy 4FCT is a single-operator, continuous
haulage system that conveys product from the face
to the panel belt, while simultaneously tramming
and following the continuous miner through multiple
drive sequences. From this truly continuous mining
method, operations are greatly enhancing zero harm
initiatives while realising a considerable increase in
tonnage output when compared to their previous use of
typical batch haulage methods.
Continuous haulage advantages
The Joy 4FCT improves safety by combining all haulage
into a single system, operating at a low tram speed and
following a fixed path of travel, while requiring only one
operator using remote control. This reduction in the
total number of mobile machines in the section reduces
visibility concerns as well as dust generation from
multiple travelways. Owing to a chain traction system
distributed along the entire length of the machine, the
4FCT offers greater traction and a lower ground bearing
pressure over that of conventional haulage machinery.
Also, the 4FCT’s integral continuous mining power cable
management reduces trailing cable damage.
The machine delivers improved productivity through its
ability to more than double tonnage output per miner
personnel, when compared to batch haulage applications
– first by eliminating the bottlenecks and car wait times
typically associated with batch haulage – and next, through
a number of design innovations.
The Joy 4FCT incorporates an integrated inby lumpbreaker,
which eliminates the need for a separate feeder-breaker in
the section. The system also offers belt advance automation
as well as automated retreat mining capabilities, made
possible by the inclusion of a Dynamic Move-Up Unit
(DMU). Acting as an interface between the Joy 4FCT and
Joy 4FCT continuous
haulage systems
With seven installations of the Joy Flexible Conveyor Train
(Joy 4FCT) globally – all operating in room and pillar
extraction and an upcoming installation in longwall entry
development – more and more operations are reporting
significant advances in safety and productivity through
the use of continuous haulage technology.
the mine’s panel belt, the DMU and Joy 4FCT are available
in two configurations: a side discharge for low seam
heights and wide entries; or an over-the-top unit (OTT)
suited to higher seams and restricted widths. Note that the
OTT system is a self-advancing unit with remote controlled
panel belt move-ups; and can also be designed for retreat
mining. The side discharge design must be advanced using
the continuous miner to pull up.
Productivity data from the field
The first Australian installation of the Joy 4FCT began in
2010, the first 4FCT system with retreat mining capability
and dual-function radio remote control. Depending
upon the panel layout and entry dimensions, mines such
as the one in Australia may realise up to 75 percent
additional utilisation of reserves when using the retreat
mining method.
A room and pillar installation in the US Illinois Basin
operates in a seam height of 2.4m and has reported a best
month of 200 914 tons. It’s best day, consisting of two nine-
hour production shifts, is recorded at 413m advancement,
totalling 10 250 tons. Also significant is that the continuous
miner in front of the Joy 4FCT, was a Joy 12CM27, that
had already recorded 3.1-million tons.
Continuous haulage methods deliver an average of 30
percent more productivity over batch haulage methods.
The Joy 4FCT increases the safety and productivity of
mining operations by eliminating car waiting times,
decreasing the amount of section equipment and
the number of section personnel required, easing
the management of cable systems and equipment
proximities, and boosting production through automated
belt advancement and retreat mining capabilities.
T he VZ-400, purchased from 3D Laser Mapping,
will be used to determine off-line and grade mining
at the Mponeng Mine in South Africa, where depths
are currently over two kilometres below sea level.
The use of high speed, high accuracy, non-contact
laser data acquisition will help improve operational
efficiencies and reduce the risk to personnel working
in the active mine.
“We tested laser scanners from many manufacturers
before selecting the RIEGL VZ-400,” comments
Michael Harcombe, Senior Mine Surveyor at
Anglogold Ashanti’s Mponeng Mine. “The virgin
rock temperature is around 60 degrees Centigrade
and working temperatures tend to be between 30
and 35 degrees. At these ambient levels, sensitive
equipment, such as laser scanners, simply do not get
the opportunity to disperse the heat they generate, so
tend to overheat and stop operating! This is not an
issue with the RIEGL VZ-400.”
Laser scanner at world’s
deepest gold mine
Anglogold Ashanti has purchased a high speed laser
scanner to support mining operations at the world’s
deepest and most substantial gold mine.
Joy Flexible Conveyor
Train (Joy 4FCT).