Trucks Tramline

A prime example of this is the hydraulic pressure
packing system. Faced with continuous electrical prob-
lems from the electrical control system and leaks and
failures from the hydraulic piping, Cassiar staff re-
designed and simplified the electrical circuit and had
a solid manifold built for the hydraulic circuit on
which are mounted all the control solenoids (Fig. 3).

This type of change, together with the use of new
lining materials in heavy wear points, different types
of belts, etc., is beginning to result in very noticeable
improvements in the operation.

Power Plant

One of the important parts of Cassiar’s operation is
its powerplant. Without it we would have no electricity
or steam heat in the plant, the mine or the townsite.

The powerplant started in 1952 as a small log cabin
housing two small diesel generators of 50-kw capacity.
By the mid 60’s, the plant had grown to an 80-ft
(24.4-m) by 82-ft (25-m) Butler building housing eight
2300-volt diesel generators with a total capacity of
3673 kw. Power was then distributed to the mill,
plant and townsite via four 2300-volt feeders. The
mining shovels and drills, being either diesel powered
or having separate diesel generators, were not con-
nected to the powerplant system. There was, however,

FIGURE 5 — 1400-kw generator in the powerhouse.

Shovels

a 13.8-kv overhead line with step-up and step-down
transformers to supply mine auxiliary power and the
crushing plant.

Ten years later, the power consumption at the site
has risen from 1964’s output of 14 x 10° kw hours to
the present 43.3 x 10° kw hours, with a projected in-
crease of 12.9 x 10° kw hours/year due to a new plant
in 1978. To keep up with this, the size of the diesel
generating units has had to be changed and an extra
bay added to the building. There are now nine units
installed, with a total rated capacity of 11,672 kw. Only
one of these dates back to 1964. (Table 1 and Fig. 4.)

All units generate at 2300 volts and feed onto an
ITE switchboard, with feeders supplying the mine,
mill, townsite and powerplant auxiliaries.

It is a simple statement to say that additional en-
gines have been installed to cope with a threefold in-
crease in power. However, many other changes have
had to be made to cope with the increased installations.

A new control room, new crane and lube systems
have been installed over the past 18 months. Within
the next few months, a new engine cooling system will
be commissioned, using forced-draught cooling towers
in a closed-loop system. The present system, one that
has been in use for many years with little change, is
open ended. Cooling water is pumped from a nearby

FIGURE 6 — Main 2300-volt switchboard in the new control
room.

450

ae en a Ne ee ee ee