CHAPTER 7
AUXILIARY MACHINERY
Information related to much of the auxiliary
machinery aboard ship is provided in Engineman
3 & 2, NAVEDTRA 10541 (current revision).
This chapter provides additional information on
the care and maintenance of compressed air
systems and equipment, auxiliary boilers,
hydraulic systems, distilling plants and pressure
valves.
COMPRESSED AIR SYSTEMS
Qualifications for lower rates require that you
know not only the purpose and principles in-
volved, but also the operation and performance
of routine maintenance on many auxiliary systems
and units which use compressed air. As an EN,
you have already used compressed air for such
jobs as starting diesel engines, blowing out and
cleaning various units, and operating numerous
pneumatic tools. When working with any of the
three types of compressed air systems (low,
medium, and high pressure), you have probably
found that the principal source of many troubles
is to be found in the compressor. Even though
the design and capacity of compressors vary, the
maintenance procedures are essentially the same
for all of them. However, the care and
maintenance of high pressure compressors require
additional safety precautions and adherence to
procedures recommended by the manufacturer.
Because of your past experience, parts of the
following discussion will serve only as a review,
while other portions of the discussion will benefit
you in your study for advancement, and will be
helpful when you are called upon to train others.
To avoid unnecessary damage to equipment,
always use proper tools and take all necessary
precautions. The correct use of proper tools
should be kept constantly in mind when a machine
of any kind is being serviced. Remember, the im-
proper use of tools and methods may cause serious
casualties to both machinery and personnel.
Although rugged and dependable, modern
auxiliary machinery is not designed to withstand
abusive treatment. Gasketed joints, pipe joints,
and bolts are designed to safely withstand the
strain required for a tight connection when the
specified torque is applied with the correct tool.
Whenever a joint or bolt cannot be tightened
without the use of an oversized wrench or wrench
handle extension, there is usually something
wrong with the assembly.
Pounding on a wrench to acquire additional
force usually results in damage to the equipment.
Use of a wrench extension is likely to distort the
gasketed surface or twist off the bolt without
achieving a tight joint. The application of any
force in excess of the force prescribed usually
results in breakage.
CARE AND MAINTENANCE OF
AIR COMPRESSORS
To keep the ship’s air compressors operating
efficiently at all times and to prevent as many
troubles as possible, it is necessary to know how
to care for air intakes and filters; how to main-
tain and replace air valves; how to take care of
air cylinders, pistons, and wrist pins; how to
adjust bearings and couplings; and how to
properly maintain the lubrication, the cooling, the
control, and the air systems.
Air Intakes and
Intake Filters
The satisfactory operation of any compressor
is based on a supply of clean, cool, dry air. To
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