straightening, facing, remachining, or resurfacing) to
restore serviceability to an item by correcting specific
damage, fault, malfunction, or failure in a part,
This appendix provides a summary of the maintenance
subassembly, module (component or assembly), end
operations for PH-637D/PFP. It authorizes categories of
item, or system.
maintenance for specific maintenance functions on
That maintenance effort (service
repairable items and components and the tools and
action) necessary to restore an item to a completely
equipment required to perform each function. This
serviceable/operational condition as prescribed by
appendix may be used as an aid in planning
maintenance standards (i.e., DMWR) in appropriate
technical publications. Overhaul is normally the highest
degree of maintenance performed by the Army.
Maintenance functions will be limited to and defined as
Overhaul does not normally return an item to like new
a. Inspect. To determine the serviceability of an
Consists of those service/actions
item by comparing its physical, mechanical, and/or
necessary for the restoration of unserviceable equipment
electrical characteristics with established standards
to a like new condition in accordance with original
manufacturing standards. Rebuild is the highest degree
b. Test. To verify serviceability and to detect
of materiel maintenance applied to Army equipment.
incipient failure by measuring the mechanical or
The rebuild operation includes the act of returning to zero
electrical characteristics of an item and comparing those
those age measurements (hours, miles, etc.) considered
characteristics with prescribed standards.
in classifying Army equipments/components.
c. Service. Operations required periodically to
keep an item in proper operating condition, i.e., to clean
(decontaminate), to preserve, to drain, to paint, or to
a. Column 1, Group Number. Column 1 lists group
replenish fuel, lubricants, hydraulic fluids, or compressed
numbers, the purpose of which is to identify components,
assemblies, subassemblies, and modules with the next
d. Adjust. To maintain, within prescribed limits, by
bringing into proper or exact position, or by setting the
b. Column 2, Component/Assembly. Column 2
operating characteristics to the specified parameters.
contains the noun names of components, assemblies,
e. Align. To adjust specified variable elements of
subassemblies, and modules for which maintenance is
an item to bring about optimum or desired performance.
Calibrate. To determine and cause corrections
c. Column , Maintenance Functions. Column 3
to be made or to be adjusted on instruments or test
lists the functions to be performed on the item listed in
measuring and diagnostic equipment used in precision
column 2. When items are listed without maintenance
Consists of comparisons of two
functions, it is solely r purpose of having the group
instruments, one of which is a certified standard of
numbers in the MAC and RPSTL coincide.
known accuracy, to detect and adjust any discrepancy in
d. Column 4, Maintenance Category. Column 4
the accuracy of the instrument being compared.
specifies, by the listing of a "work time" figure in the
G. Install. The act of emplacing, seating, or fixing
appropriate subcolumn(s), the lowest level of
into position an item, part, module (component or
maintenance authorized to perform the function listed in
assembly) in a manner to allow the proper functioning of
column 3. This figure represents the active time required
the equipment or system.
to perform that maintenance function at the indicated
h. Replace. The act of substituting a serviceable
category of maintenance. If the number or complexity of
like type part, subassembly, or module (component or
the tasks within the listed maintenance function vary at
assembly) for an unserviceable counterpart.
different maintenance categories, appropriate "work
Repair. The application of maintenance services
time" figures win be shown for each category. The
(inspect, test, service, adjust, align, calibrate, replace) or
other maintenance actions (welding, grinding, riveting,
Change 2 C-1