MINE SAFETY
The longwall system for JSW’s Budryk mine
The new face set will operate in the Cz-2 face
of the 405/1 seam at a depth of 1,290 m at the
Budryk mine. Commissioning will begin with the
extraction of seams 405/1 and 405/2, which have
totally 68.5 Mt of hard coking coal resources.
Extraction is expected to commence later this
year, or early in 2020.
The longwall system to be used in the Cz-2
face consists of 118 Becker Warkop powered roof
supports, each 1.75 m wide. The company also
took special care to ensure the safety of workers
directly at the coal face, designing, among other
things, a walkway for the crew to move through
in front of and behind the powered roof
support shield’s legs.
In accordance with the requirements of the
mine, the safety of the workers to service the
shearer has also been ensured by equipping 24
of the 118 powered roof supports with specially
designed telescopic face heading protecting
shields. This will protect the workers from falling
rocks while in place at the shearer.
Becker’s powered roof supports come with the
latest longwall automation systems and can be
operated either locally, remotely, or semi-
automated, according to the customer’s
requirements.
In seams with a longitudinal inclination of over
12°, the support collaborates with conveyor
stabilisation, roof shield correction, and main gat
face-end protective devices.
shaped steel guides and, according to the
company, offers superior safety and other
operational benefits to underground mining
companies.
It uses steel guides instead of conventional
timber guides to eliminate uncertainties inherent
with wood and provide an enhanced degree of
safety, repeatability and reliability, the company
said.
“The Cage Guardian Safety Brake is strictly
mechanical – no hydraulics, pneumatics or
electricity – for fail-safe operation, even on wet
or contaminated guides,” FLSmidth said.
“Actuation and operation is performed by
redundant mechanical systems, only requiring a
slack-rope or rope break event to bring the cage
to a safe stop.”
It also comes with average deceleration rates
of 0.9 g to 2 g (9 to 20 m/s/s) meaning the Cage
Guardian Safety Brake has a lower jerk rate and
Cages and shafts
FLSmidth says it is delivering on a promise to
provide solutions for a sustainable tomorrow
with its Cage Guardian™ Safety Brake for steel
guides.
Designed for underground mining operations,
the Cage Guardian Safety Brake is used on
conveyances running on tubular or top-hat-
International Mining | OCTOBER 2019
FLSmidth’s Cage Guardian Safety Brake uses
steel guides instead of conventional timber
guides to eliminate uncertainties inherent with
wood and provide an enhanced degree of safety,
repeatability and reliability
provides smoother deceleration than other such
brakes on the market, according to FLSmidth.
The safety brake system also allows for easy
retrieval of the cage after an event, with, unlike
conventional safety dogs for wood guides, the
brake inflicting minimal damage to any cage or
guide components, resulting in faster
redeployment of the cage.
Henry Laarakker, a Product Manager at
FLSmidth, said as wood guides become
increasingly less desirable from both
environmental and economic perspectives, the
use of steel guides is becoming ever more
attractive. “The Cage Guardian opens up a new
world of opportunities for the safe transport of
personnel underground,” he said. “It also allows
for a fully-engineered safety solution, inspiring a
high degree of confidence without reliance on
the variability of nature inherent with wood
guides.”
Still within the underground mining safety
space, Winder Controls Australia, a subsidiary of
the SIEMAG TECBERG group, recently launched a
gravity feed system for safe personnel recovery
in the event of a power loss or control system
malfunction.
This system involves the use of a standalone
control system and generator to ensure the
gravity feed system is isolated from any
malfunctions/power loss with the winder.
The company explained: “This arrangement
ensures that personnel recovery operations are
conducted in a safe and controlled manner
without exposing trapped or recovery personnel
to any additional risks.”
It relies on the drum, brake callipers and
piping to the callipers being fully functional, with
all other components and systems assumed
inoperable. The gravity feed system allows the
conveyance to be lowered at a controlled speed
of 0.7-1 m/s to enable personnel to be safely
evacuated at an underground level.
Single rope drum winders are the primary
application for this system, but the company
says it can be employed on other hoisting
systems where the conveyances are not
balanced. A similar system has also been
developed for a standard friction winder with a
pony drive system capable of bi-directional travel
to enable personnel to be evacuated at surface
or any underground level. This is conducted at a
speed of 0.25-0.5 m/s.
“Without a system in place for personnel
recovery, mines are forced to use primitive or
unsafe recovery methods,” the company said.
These methods often involve acquiring
equipment off-site, which exposes personnel to
more potential risks.
The company worked with regulators and
miners to develop this fit-for-purpose system,
which is SIL-2 compliant. Winders Controls