track ropes. Haul-rope lubrication is provided by drip
feeders at the loading and discharge terminals. Pe-
riodic tightening of bolts in structures and constant
checking of the track ropes is also achieved during
the running cycle.

Perhaps the most time-consuming area of main-
tenance is that concerned with the track and haulage
ropes. As soon as a broken wire is spotted on a track
rope, a metal cuff must be fitted before the wire comes
out of lock. As may be expected from studying the
entry and exit of the car from a tower, the majority of
the damage occurs within 20 to 30 ft (6.1 m to 9.15 m)
of the tower. To relieve constant wear on the rope in
one area, a program of rope slipping is carried out on
a scheduled basis. Generally the rope is slipped in its
direction of travel, but this is sometimes changed in
order to ‘bury’ the damage within the saddle area.
Rope slipping and retensioning now takes about 1%
days/rope, as the rope may be moved 10 ft (3 m) to
12 ft (3.5 m), at 6 inches (15.25 cm) at a time. Ten-
sioning itself is a time-consuming item; this is done
at least twice a year, in fall and spring. The tension
is adjusted by means of hydraulic jacks to a pre-set
value. (Table 4).

However, because of the friction between rope and
saddle, the rope must first be broken free, often with
the use of a chain hoist. Getting the rope to the right
tension and properly balanced with its partner can be
a long and frustrating exercise. Although grease fit-
tings are designed into the new type of saddles to help
reduce friction, it is very obvious that we must design
something to speed up the slipping and tensioning
process.

Once a rope develops too many broken strands in an
area, it must be replaced. The method employed for
replacing the bottom ropes is to first suspend the cars
from the top ropes using load binders and chains. A
winch, the new rope and the empty drum are then
positioned at one end, with a second winch at the other
end. The old rope is pulled out and wound directly onto
the empty drum. At the same time, a rope from the
winch at the fore-end is attached to the old rope and
pulled through the towers. Once the old rope is moved
out of the way, the end of the new rope is attached to
the winch line and pulled back into place. The initial
tension of 80,000 lb is put into the new rope by using
the winch and an 8:1 block and tackle. Final tensioning
is done using hydraulic jacks.

Changing the top ropes requires a different tech-
nique. On the first attempt, the cars were pulled back
from the section being changed. However, the haul
ropes became so tangled that it was later decided to
remove all the cars from that section and store them
on the ground. This obviously is a time-consuming job.
On the next rope change, we plan to install a dummy
rope to support the cars during the change. How suc-
cessful this will be we can only guess — having not
yet tried it.

Haul-rope inspection is also done visually, with a
close inspection every three weeks when the cars and
pins are greased. The replacement program being used
for haul ropes is to have the ends cut off, resocketed
and tested at about 1.5 x 10° tons and to replace the
whole rope at about 3 x 10° tons. As we have only car-
ried 2 x 10° tons on the tramline to date, it is impos-
sible to say if this is the right formula. It is, however,
recommended by the manufacturer of the ropes and
other operations.

Up until now, all the in-situ rope tests have been
visual, but we hope to try a tramcar-mounted electro-

The Cassiar tramline, with typical mountain scenery in the
background.

TABLE 4 — Chart of Tensions for Ropes

Tension in Fall

Tension in Spring
(Tension in Kips)

(Tension in Kips)

2-%4-in. 2-in.
Top Bottom
Track Track

190 145 145
180 138 138
170 131 131
160 124 124
150 117 117

2-in.
Bottom
Track

magnetic unit in the near future. If successful, this
would indicate any broken strands inside the rope as
well as on the surface.

Other maintenance procedures, such as shimming
tower rails to maintain a good rail rope transition
or changing the grip units on the drive wheel, are still
being done on an as-required basis until we have suf-
ficient information to indicate the best timing. In fact,
with the number of modifications now being incor-
porated, it will probably be at least two more years
before we will be able to formulate a reliable scheduled
maintenance program.

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