OPERATION AND MAINTENANCE OF
Electric solenoid valves will usually require
SUPPORT AND AUXILIARY SYSTEMS
component replacement instead of repair. The whole
assembly is divided into two parts, the solenoid and the
Up to now, we have talked about some of the
valve. The diaphragm in the valve is the only minor part
components associated with the support and auxiliary
in the whole assembly that can be replaced to effect a
systems. You should realize, however, that these
minor repair. In most cases, you will have to replace
components are just a small portion of the total design
and operation of these systems. In this section, we will
tell you how these components interact to make the
Valve Operator Mechanical Linkages.
support and auxiliary systems work. Although we will
Mechanical linkages are designed to provide years of
briefly describe how the systems operate, we will focus
trouble-free service when properly maintained.
primarily on their maintenance and repair.
Probably the leading cause of operator failure is
negligence. This statement pertains to both types of
SHIP'S SERVICE AIR SYSTEMS
operators we have discussed. For example, an operator
will work fine until it has to be detached from the valve
or component it is operating. Then, during reassembly,
The ship's service air system (SSAS) on a gas
a bracket bolt may be missing. Instead of finding a
turbine-powered ship is used extensively everyday. It
replacement, you might think "Oh well, one bolt will
supplies air for maintenance, service, control,
hold it." The problem is there are usually two bolts per
pneumatic power, and other utilities. All of these
bracket. Using one bolt will definitely cause a
services come under one or more of the four subsystems
misalignment in the operator. If both bolts are missing
we will describe in the following paragraphs.
and you are tempted to install bolts of the wrong size,
you will still cause the operator to be out of alignment.
Electronics Dry Air System
Shipboard repairs to rigid rod-type operators will
The electronics dry air system is a vital system in
normally consist of freeing up a binding universal joint
which the air is dried twice. Before entering the system,
or gearbox, replacing the packing, and tightening or
the air passes through a condenser filter and then a type
replacing any loose or missing support bracket bolts.
11 dehydrator. The electronics dry air system services all
Binding universal joints are usually caused by excessive
electronic systems, AC plants, and gun and missile
bends or operator misalignment, as we have already
control panels that require dry air.
discussed. Depending on the operator's age, however,
the joint may be worn out and you will need to replace
Ship's Vital Air System
it. In most cases, the joint will be attached to the operator
rod end by a removable pin. If necessary, you can drive
The ship's vital air system produces air that is dried
out the pin with a punch. You can then remove the joint
only once. The only difference between the vital and
and install a new one.
nonvital air systems is the equipment serviced. The
Gearbox repairs will be more difficult and in some
ship's vital header services the sonar dome, ammo
cases impossible to perform. Many of the gearboxes are
elevator, close-in weapon system (CIWS), No. 3 GTG
sealed units and repairs cannot be made. Even if the
signal air, and many others.
gearboxes can be opened, you must call on your
machinery repairman to manufacture the new gears. If
MER Vital Air System
the materials and equipment are available, you might be
successful. In most cases, however, it is easier to order
Like the ship's vital air system, the MER vital air
a new part.
system is tapped off the main header just before the
Even though the flexible valve operators have fewer
priority valve. This tap location ensures that all vital
parts than the rigid operators, shipboard repairs to
equipment will have air if there is high air use or a leak
flexible valve operators are usually limited by the
occurs in the nonvital subsystem. This air is for vital
propulsion equipment. It is also the receiving piping for
availability of parts. This means most repairs must be
emergent y air from the HP/LP air reducing station. On
accomplished by outside activities. Depending on the
the CG-47, DD-963, DDG-993 class ships, there is one
problem, sometimes the repair personnel can make the
repairs while leaving the operator in place. If this is not
HP/LP air reducing station located in MER No. 1. On
possible, the whole operator should be removed and sent
the DDG-51 class ships, there are two HP/LP air
reducing stations, one in each MER.
to an outside repair facility.