- Keep the oil cooler free from leaks (since
pressure on the water side exceeds that of the oil) to
prevent oil contamination and emulsification.
- Properly adjust the lubricator for the specified
quantity of oil feed.
COOLING SYSTEM
Proper care of a compressor cooling system
includes the following inspections and maintenance
procedures:
- Periodically inspect the intercoolers and
aftercoolers.
- Remove collections of gummy oils or tarry
substances from the cooler tubes by washing tube nests
with a suitable solvent and drying them thoroughly
before reassembling.
- Correct any leakage in tube nests to prevent
leaks of water into the compressor while secured or
leaks of air into the water side during operation.
- Inspect and clean the cylinder water jackets
periodically with a cleaning nozzle.
When filling the cooling water system after the
compressor has been drained, open the water inlet
slightly to allow the water to rise slowly in the cooler
shells and water jackets. Vent valves fitted to the water
spaces should be opened to permit entrapped air to
escape and to remove any air pockets.
CONTROL DEVICES
Because of the great variety of regulating and
unloading devices used on compressors, you will have
to consult the manufacturer’s technical manual for
information regarding the adjustment of these devices
on particular compressors.
If a control valve fails to work properly, it should be
taken apart and cleaned Some valves are fitted with a
filter filled with a sponge or woolen yarn to prevent
particles of dust or grit from being carried into the valve
chamber. These filters remove gummy deposits from the
oil used in the compressor cylinders. When repacking,
use only genuine wool. Cotton will pack and stop the
airflow. Relief valves are very important for safe
compressor operation. They should be set as specified
by the manufacturer and lift-tested by hand each time
the compressor is placed in operation. To check the
setting periodically, test by raising the pressure in the
spaces to which they are attached.
SUMMARY
Since an Engineman may encounter so many types
of compressed air systems, air dryers, and air
compressors both ashore and aboard Navy vessels, this
chapter presented only general procedures and facts. To
maintain, repair, and overhaul specific compressed air
systems, air dryers, or reciprocating air compressors,
you must refer to the manufacturer’s technical manuals.
A definite preventive maintenance schedule with
frequency and assignment of responsibility is required.
You should have the manufacturer’s manual handy to
establish minimum requirements and to follow its
recommendations for maintenance.
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