Figure 7-14.--Typical eductor system.
and throat bushings. Always check the shaft align-
ment with all the piping in place.
Some driving units are connected to the
pump by a FLEXIBLE COUPLING. A flexible
coupling (fig. 7-15) is intended to take care of
only a slight misalignment. Misalignment should
never exceed the amount specified by the pump
Figure 7-14 is an example of a typical ship-
board eductor system. Note that the eductor
discharge piping is below the water line. The
swing-check valve above the overboard-discharge
valve prevents water from backing up into the
system if the system pressure drops below the out-
side water pressure. To prevent engineering spaces
from flooding, you must follow the step-by-step
procedures that are posted next to eductor
ALIGNMENT OF SHAFT
When you install or assemble pumps driven
by electric motors, ensure that the unit is aligned
properly. If the shaft is misaligned, you must
realign the unit to prevent shaft breakage and
damage to bearings, pump casing wearing rings,
Figure 7-15.--Grid-type flexible coupling.