Before contacting Lubrication
Engineers, the only option open to the
maintenance team at Tahmoor was to
manually lubricate the drift rope. This
process was not only time consuming
and messy but also required the staff to
directly interact with the rope, which
increased the risk of injury.
Further, the process of manually
lubricating wire ropes does not achieve
the same end result with uneven
application and minimal penetration of
the lubricant into the core of the rope.
This reduces the effective protection the
rope has once it is placed in service and
will lead to reduced wire rope life.
The process of manually lubricating
the drift rope at Tahmoor included:
n
Rope detail: 67 mm dia. (2-5/8 in.)
drift rope, approximately 370 m in
length.
n
Time frame: two men, working 12 hr
each (24 hr in total), were required
to manually lubricate the rope by
hand with paint brushes.
n
Lubricant usage: they were using
approximately 10 x 20 kg pails of
grease – a total 200 kg of grease on
each occasion, which equates to
800 kg/yr.
n
Lubrication frequency: every three
to four months (i.e. four times per
year).
The following is the basic cost
breakdown of this manual process:
n
Lubricant: Caltex Moly Grease
§
US$275 per 20 kg pail x 10 =
US$2750 per lubricant.
§
Four times per year (every three
months) = US$11 000/yr.
n
Labour:
§
Two men, 12 hr at US$60/hr,
(24 hr in total) = US$1440 per
lube.
§
Four times per year (every three
months) = US$5760/yr.
n
Annual cost: approximately
US$16 760/yr to manually lubricate
the drift rope.
Lubrication Engineers introduced the
Viper Mid Wire Rope lubricator to the
maintenance staff at Tahmoor and
demonstrated how straightforward the
Viper WRLmade it to lubricate wire
ropes from 8 mm up to 165 mm in dia.
The heart of the Viper WRL is the
specifically designed Viper Seal that
works to force lubricant into the valleys
and ultimately the core of the rope.
Contained within a cast alloy collar that
is easy to fit onto the rope and then
matched to the lubricant supply pump
arrangement, the Viper WRL is
considered an effective method of
lubricating almost all wire ropes.
Once the maintenance team at
Tahmoor had a clear understanding of
how the Viper WRLwas set up and
operated, they were keen to give it a try
on the drift rope at the site.
The Viper Mid MKII WRLwas set up
on the drift rope, with the correctly
selected VSEAL (seal) and associated
VSCs (scrapers). In addition to the basic
set up, Tahmoor agreed to use one of the
Viper WRL rope cleaners to remove old
lubricant and contamination from the
rope before it entered the Viper Mid
collar. By removing the old lubricant and
any contamination stuck to the rope, the
physical lubrication process is much
more effective, with more lubricant
covering and penetration.
The company also recommended the
use of the VCG‑1 lubricant for this
application, due to its ability to cling to
the rope, while gradually working into
the core. The following are the details of
the process, with the Viper WRL
performing the task:
n
Time frame: using the Viper it now
takes two men only 4 hr (8 hr in
total) to lubricate the rope with Viper
Mid Mk II Wire Rope Lubricator.
n
Lubricant usage: 1 x 180 kg drum of
VCG‑1 was used, which is sufficient
to complete two lubrication
process (approximately 90 kg per
lubrication).
n
Lubrication frequency: due to
the increased effectiveness of the
lubrication process using the Viper
Mid WRL, the site now only has to
lubricate this drift rope every six
months (twice per year).
While the obvious benefits of a more
effective, simpler and safer rope
lubrication process were significant to
the site maintenance staff,
improvements in the cost of lubrication
are also worth noting.
n
Lubricant: VCG‑1 grease
§
190 kg = US$4520.
§
This drum lasts twelve months
(two lubricant sessions) =
US$4520/yr.
n
Labour:
§
Two men, 4 hr at US$60/hr
(eight hours in total) = US$480
per lube.
§
Twice per year (every six
months) = US$960/yr.
n
Annual cost: approximately
US$6890/yr to lubricate the drift
rope using the Viper Mid Mk II Wire
Rope Lubricator.
n
Annual saving: approximately
US$9870/yr.
The move to the Viper Mid MKII
WRL has proven to be an easy decision
The Viper Mid MKII WRL in place ready
to lubricate the drift rope.
The drift rope exiting the Viper Mid MKII
WRL, clean and lubricated.
24
|
World Coal
|
December 2015
