e
general arrangement of the special auxiliary plant necessary for
carrying through a consumption test, when the turbine exhaust passes
through a surface condenser. The condensed steam, after leaving the
condenser, passes along the pipe A to the pump, and is then forced along
the pipe B (leading under ordinary circumstances to the hot-well),
through the main water valve C directly to the measuring tanks. To enter
these the water has to pass through the valves D and E, while the valves
F and G are for quickly emptying the tanks when necessary, being of a
larger bore than the inlet valves. The inlet pipes H I are placed
directly above the outlet valves, and thus, when required, before any
measurements are taken, the water can flow directly through the outlet
valves, the pipes terminating only a short distance above them, away to
an auxiliary tank or directly to the hot-well. Levers K and L fulcrumed
at J and J are connected to the valve spindles by auxiliary levers. The
valve arrangement is such that by pulling down the lever K the inlet
valve D is opened and the inlet valve E is closed. Again, by pulling
down the lever L the outlet valve F is closed, while the outlet valve G
is also simultaneously closed.

[Illustration: FIG. 70]

During a consumption test the valves are operated in the following
manner: The lever K is pulled down, which opens the inlet valve to the
first tank and closes that to the second. The bottom lever L, however,
is lifted, which for the time being opens the outlet valve F, and
incidentally opens the valve G; the latter valve can; however, for the
moment be neglected. When the turbine is started, and the condensed
steam begins to accumulate in the condenser, the water is pumped along
the pipes and, both the inlet and outlet valves on the first tank being
open, passes through, without any being deposited in the tank, to the
drain. This may be continued until all conditions are right for a
consumption test and, the time being carefully noted, lever L is quickly
pulled down and the valves F and G closed. The first tank now gradually
fills, and after a definite period, say fifteen minutes, the lever K is
pushed up, thus diverting the flow into the second tank. While the
latter is filling, the water in the first tank is measured, and the tank
emptied by a large sluice valve, not shown.

The operation of alternately filling, measuring, and emptying the two
measuring tanks is thus carried on until the