Cleaning and Lubrication
Cleaning is a continuous task. As a GS supervisor,
you are already aware that good housekeeping practices
must be maintained and passed on to your subordinates.
The responsibilities for cleaning and lubricating the
components of the CRP/CPP systems are very similar
to those for the MRG LO system. This is because the
majority of the components that require cleaning in both
the MRG LO system and the CRP/CPP systems are
valves. When cleaning the valves of the CRP/CPP
systems, be sure to pay close attention to detail.
Attention to detail is important because most of the
valves and piping of the CRP/CPP systems are located
in the bilge area. Valves in the bilge area are constantly
exposed to corrosive elements.
Other components that require cleaning and
lubrication are the two CRP/CPP pump couplings.
These pump couplings are not cleaned and lubricated as
frequently as the valves, but their cleaning and
lubricating are still very important responsibilities.
Alignments and Adjustments
You will routinely supervise alignments and
adjustments to couplings and other system components.
Your personnel usually perform these tasks after general
maintenance (cleaning and lubrication). Alignments
and adjustments are either scheduled or conditional.
During the cleaning process, for example, you may
discover that a coupling requires an alignment check or
adjustment.
The CRP/CPP system is one of the few systems that
you as a supervisor will be required to train your
personnel to closely monitor locally. Local monitoring
is necessary because of the lack of remote monitoring
capabilities.
You will also be required to train your
personnel to make the necessary mechanical and
electrical adjustments. Your personnel will periodically
perform these procedures through your ships PMS.
Remember, first you must monitor the operation of the
CRP/CPP system as a whole, and then isolate individual
components (one at a time) to ensure they are
functioning properly. The following paragraphs contain
some of the components you maybe required to adjust
and the functions they are designed to perform.
UNLOADING VALVE. The unloading valve
unloads the pressure of the attached pump back to the
sump if the electric pump is operating and functioning
properly.
SEQUENCING VALVE. The sequencing valve
serves two purposes:
(1) It maintains a back pressure on the system to
ensure that a minimum of 400 psi is supplied to the inlet
side of the reducing valve, and (2) it provides
high-pressure oil to the OD box.
REDUCING VALVE. The reducing valve
provides control oil to the OD box.
AUXILIARY SERVO RELIEF VALVE. The
auxiliary servo relief valve relieves excess control oil
pressure back to the sump.
MAIN RELIEF VALVE. The main relief valve
relieves excessive pump pressure, either from the
electric pump or attached pump, back to the sump.
Besides adjusting the components at the OD box,
both mechanical and electronic pitch position alignment
checks must be accomplished periodically. These
checks will not only require your expertise to train your
personnel, but also require your presence while they are
being accomplished.
MECHANICAL ALIGNMENT. The mechani-
cal alignment procedure is basically the same for all the
ship classes. This procedure is performed according to
the PMS and is used to detect valve rod separation
(unscrewing) or elongation. Remember, two people
will be required to perform this check One must be
positioned at the OD box and the other at the HOPM,
and they must be able to communicate with each other
(sound-powered phones or walkie-talkies). This test is
normally fairly easy to accomplish if no problems are
encountered. By problems we mean the pitch scale and
the pitch position pointer being off by more than 1/16 of
an inch.
If this difference cannot be explained by
thermal growth or contraction of the valve rod assembly,
it will be necessary to verify that all connections in the
valve rod assembly are tight. If the position of the
pointer and pitch scale is subject to question at anytime,
you must verify actual position of blade 1A to the hub
body marks. If the ship is not in dry dock, you must use
a diver to observe and confirm hub body marks. You
must have confirmation of the hub body marks at design
ahead and full ahead when pitch is ordered at normal
operating temperatures.
NOTE
In most cases, an equipment malfunction is not
the cause of the pointer and scale discrepancy.
Usually, it is an operator error. To avoid this problem,
make sure your personnel strictly follow the MRC
and always take all measurements at the same system
oil temperature.
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