These inspection requirements are for the LO
monitored. By consistently using good maintenance
filter/strainer assemblies installed in the CG-47,
habits and the PMS as a scheduling tool for routine tests
DD-963, and DDG-993 class ships. The inspection
and inspections, you can ensure the optimum
requirements for the LO filters installed on the DDG-51
performance from your system. In the following
and FFG-7 class ships are different. That is why you
paragraphs, we will describe some of the components in
should always strictly follow the requirements listed in
the LO system and the most commonly performed tests
the EOSS and PMS for your ship.
and inspections. As a GSM, you will be responsible for
either performing these tests and inspections or making
sure they are completed correctly.
Lube Oil Pump Logics
Lube Oil Strainer/Filter Assembly
On most gas turbine ships, the LO pump logics are
routinely tested semiannually. In reality, however, this
test is usually performed more frequently because your
Of all the components in the MRG LO service
ship will perform safety checks for various training and
system, the strainer or filter assembly will probably
inspection evolutions throughout the year. These checks
receive the most attention. On CG-47, DD-963, and
and inspections will include tests of the LO pump logics.
DDG-993 class ships, the filter/strainer assemblies are
frequently cleaned and inspected. In inspecting and
The LO pump logics test is fairly simple to perform.
cleaning your ship's LO strainer/filter assembly, always
I t does, however, require two people and
remember to follow the requirements listed in the EOSS.
communication lines between the LO pressure switch or
You should also follow the requirements listed in NSTM,
pressure transducer and the control console. The
chapter 262, "Lubricating Oils, Greases, Hydraulic
performance of this test is almost the same as that for
Fluids and Lubricating Systems." The requirements
the FO pump logics test. For the LO pump logics test,
listed in NSTM, chapter 262, may exceed those listed in
however, the desired results are different because the
your ship's EOSS. In this case, you should follow all the
operational design of the LO system is different from
requirements in your EOSS and those described in
that of the FO system. During a continuous loss of
NSTM, chapter 262, that are not included in your EOSS.
pressure, for example, the FO system will stop, whereas
In the following paragraphs, we will tell you about the
the LO pumps will continue to operate. Analysis has
requirements set forth in NSTM, chapter 262, as they
shown that a continuous small amount of oil provided
pertain to your responsibilities for maintaining the
to a multimillion dollar MRG is less likely to cause
components of the MRG LO service system on CG-47,
massive damage than no oil at all.
DD-963, and DDG-993 class ships.
Normally, you should shift and inspect the main
propulsion LO strainer baskets once a day. Under the
CLEANING AND LUBRICATION
following circumstances, you must shift and inspect
these baskets once each watch:
Cleaning and lubrication of the MRG LO service
system are continuous tasks. Proper lubrication of the
When you detect any indication that pressure
components of this system is vital for system
differential has shifted from normal or when any
performance and safety. Let's take a look at some of the
other symptom of abnormal operation (such as
components that will need frequent cleaning and
high bearing temperatures) is seen
lubrication.
For the first 24 hours of operation following a
shutdown in excess of a week, after rough
weather, or any time you notice an abnormal
Valves
pressure differential (in excess of 1.5 lb/in2)
through the strainer
Most of the components in the MRG LO service
system that will require frequent cleaning and
For the first 48 hours of operation after repairs to
lubrication are valves. In cleaning and lubricating these
the LO system or to any equipment serviced by
valves, you must pay close attention to details because
the LO system have been made
most of this system's piping and valves are located in
the bilge area. Being in the bilge area means that the
When the propulsion plant is operating at more
than 85 percent full power
valves are constantly exposed to corrosive elements.
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