At some operations, the initial
installation of the voice
communications and tracking system
was safety driven in order to control
risks should an emergency situation
arise. Obviously, the ability to
communicate rapidly to all miners
underground combined with tracking
their location in real-time provides a
significant tool in the mine’s overall
emergency preparedness plans. With
that connectivity and location data in
place, the day-to-day use of the
systems grew to where it becomes
integral to the efficient running of the
mine. This use not only gives a mine
direct cost benefit, but importantly
ensures the system is always
operational since it is being used
virtually every minute of the day. If
an emergency situation were to arise,
the system is known to be operational
and available to play its role in the
management of the crisis.
On the productivity side, longwall
automation has been growing in
acceptance as a proven way to
increase production from a longwall,
as it has delivered a key aspect of any
productive process: consistent and
repeatable actions. This has been
achieved by taking away the human
element that caused so much
variation from shearer driver to
shearer driver, and shear to shear.
One of the first areas in which
automation proved itself was in
sumping at the end of, or beginning
of, a new cutting sequence. Early
adopters quickly gained significant
cycle time advantages in this part of
the shearing cycle alone, motivating
them to automate wider areas of the
cutting and advance cycle.
OEMs, such as Joy Global and
Caterpillar, are pursuing the power of
data to better understand the
operation and maintenance of the
longwall equipment. Sophisticated
monitoring through onboard
diagnostics has given an opportunity
to optimise machine performance,
plan maintenance to minimise
breakdowns and prevent catastrophic
failure. But to realise this opportunity,
the data needs to be analysed in real
time. For example, Joy has its
JoySmart Services to provide
high-level analytic services to its
mining fleet around the world from a
few of its key remote facilities.
The machines have the smart
sensors and transducers, and the mine
office is connected to the world via the
internet, and hence to Joy’s JoySmart
centres. What has been often missing is
the link between those smart machines
underground and the surface.
High‑bandwidth IP networks provide
that link by the use of good network
and management tools, as well as
techniques, such as Virtual LANs
(VLANs), that allow the IP network to
prioritise data streams and operate
securely and reliably with high data
integrity.
Focusing on underground
connectivity
Mine Site Technology (MST) has
focused its development efforts on
delivering this IP connectivity
underground. In particular, the
development efforts have not been so
much in the communication protocols
as such, that is the Wi-Fi and ethernet
communications, but in specifically
designing the devices and network
elements to meet the unique challenges
of an underground coal mine. There are
myriad Wi-Fi access points (APs)
available, but they can be termed ʻmade
for use in the carpeted spaceʼ, that is the
office and home environment and not
an underground mine.
Apart from the obvious requirement
for intrinsic safety standards, these
devices often require 110 or 240 V AC
power at each individual AP, which is
not practical in the underground
environment. Also, the physical layout
of an underground roadway means that
APs need to be easily connectable and
able to branch in different directions at
many locations. Incorporating four fibre
switches in each AP gives the required
network flexibility at each location in a
single device, thus simplifying
installation, providing power and
on-going network management.
Hence, delivering an open standard
network did require customised
components to suit the physical and
regulatory environments a coal mine
operates in.
With a suitable network in place,
higher‑level applications, such as
automation and remote monitoring, are
enabled. Besides these larger
applications, having a real-time
communications network can bring
many other smaller benefits on a
shift‑by‑shift basis that improves
performance and safety.
An hour or two saved in getting a
longwall back into production is a
benefit resulting from good
NS40 Wi-Fi AP and switch – a key
component of an underground IP
network.
MP70 MinePhone: a VoIP phone for coal
mines.
46
|
World Coal
|
June 2016
