LO holding tank. When applicable, return
MAIN LUBE OIL SYSTEM
satisfactory samples to the sump to prevent
inadvertent depletion of the sump. Never dispose
All GTE-powered ship classes have the same
of oil samples in the bilges or other pollution-
basic LO service system. In this section we will
producing areas.
describe the basic system and components and
Each ship is required to have a LO manage-
point out (where applicable) the differences in the
ment program. The LO management program has
design of some ships' LO systems. If no difference
two parts.
is noted in the description, the reader can assume
the component to be basically the same on all
1. An onboard sampling and testing program
classes of GTE-powered ships.
2. The Navy Oil Analysis Program (NOAP),
which is an off ship oil test program
SYSTEM LUBE OIL FLOW
In the onboard LO program, all designated
The pumps take suction from the MRG sump
operating machinery is sampled on a periodic
through check valves. The check valves maintain
basis. The samples are then compared to samples
system prime (that is, they ensure the suction line
of the original oil installed in the machinery. A
to the pump and the pump casing remain full) and
LO sample rack is installed in a designated area
prevent reverse flow of oil through a secured
that contains the sample bottles. The original oil
pump. The pumps supply oil under pressure to
installed in each piece of machinery is sampled.
a common line where the unloader valve returns
This sample is dated and used as the basis of
oil in excess of demand to the MRG sump. Oil
comparison for all other samples. Samples are
from the common line flows to the LO cooler,
taken on the following schedule:
where its temperature is reduced to about 120F.
From the cooler, oil flow is divided into two
1. Daily--operating machinery at sea or in
paths, one to supply the MRG and the other to
port
supply the two LOSCA coolers. Oil to the MRG
2. Prior to starting all machinery
flows through the duplex filter into the MRG lube
oil header. From the MRG header, oil is
distributed to lubricate and cool the reduction
3. After casualty to machinery
gear components, the clutch/brake assemblies,
4. When ordered by the engineering duty
and the thrust bearings. The oil then returns
officer (EDO)/EOOW
to the sump. Oil to each LOSCA passes through
a pneumatically controlled valve. This valve
controls oil flow to the synthetic LO cooler to
regulate temperature at the synthetic oil discharge.
Service system LO from the LOSCAs join in a
The sample rack contains one sample bottle
common line to return to the MRG sump.
for each piece of machinery. A log of all
SYSTEM COMPONENTS
samples taken and the condition of each sample is
maintained and initialed by designated personnel.
The reduction gear LO service system is a
closed loop system with the sump tank vented to
The NOAP provides spectrometric analysis of
the atmosphere. Circulation of the LO (as
a ship's LO at a designated laboratory. This
described in system flow earlier) is accomplished
program can be used to detect accelerated wear
by pumps. In this section we will describe the
in machinery, without the machinery being
components the LO passes through during this
disassembled, long before any other trouble is
circulation. They include (1) the LO sump, (2) the
indicated. Lube oil samples of selected equipment
LO pumps, (3) the unloading valve, (4) the
are submitted to the laboratory on a periodic basis
temperature regulating valve, (5) the LO cooler,
for examination. The ship is advised of the test
(6) the LO filter, and (7) the main LO header.
results by the testing activity. The ship maintains
accurate records of operating hours after major
Lube Oil Sump
overhauls, oil changes, and any repairs effected
as a result of recommendation by the laboratory.
The MRG lube oil sump is located in the
inner bottom beneath the MRG. The sump
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