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3.2.1 Reliability.
The requirements of this specification are imposed exclusively to
obtain equipment of  utmost reliability for the intended service.  The assurance of maximum
reliability shall be the paramount controlling principle in the design. fabrication.
assembly and testing of this l quipment.  Users of and suppliers to this specification are
urged to communicate to Naval Ship Engineering Center (NAVSEC) any findings related to the
requirements or lack of requirements of this specification whereby improvement of equipment
reliability can be achieved.
3.2.2 The equipment specified herein shall be operated, maintained and repaired on-
board Navy ships. Attention is directed to the high equipment density of shipboard machin-
ery spaces, to the fact that maintenance and repair must be made underway in heavy seas,
that equipment must operate unattended, and that maintenance personnel may not be seasoned
mechanics.  The requirement for maximum reliability directly related to these shipboard
environmental and service conditions and they shall be fully considered in the pump design.
The aspects of "human engineering" shall also be fully explored and considered in the equip-
ment design to minimize the possibility of failure through improper operation and maintenance
and to preclude personnel safety hazards.  In no ease shall parts be physically interchange-
able or reversible unless such parts are also interchangeable functionally and from con-
siderations of strength. The equipment shall be designed for maximum repair accessibility, for ease of
examination of wearing parts and for simplicity of disassembly and proper reassembly.  Posi-
tioning and alignment of parts in assembly shall employ positive means such as shoulder,
tongue and groove or other locating techniques whereby correct reassembly is repeatedly
assured.  In consonance with the concept of ease of maintenance and where not already speci-
fied, the pump designer shall consider all of the following features for incorporation in
the design and technical documentation wherever such incorporation will significantly con-
tribute to ease of maintenance without compromising performance reliability:
Lifting lugs.
Casing assembly guide pins.
Alignment and positioning dowels.
Jacking screws.
Ease of access to couplings.
Re-makeable piping connections.
Piping out of way of maintenance access.
Ease of packing, seal cage, mechanical seal, bearing and wearing ring replace-
Split casings, bearing housing, etc.
. (i)
Guards over rotating and moving components.
Warning places to prevent casualties to equipment and personnel.
Provisions for connecting instruments for performance evaluation.
Attached instruments for monitoring performance.
Visibility and access to attached instruments.
Thoroughness of operating instructions.
Thoroughness of preventive maintenance instructions.
Explicit assembly and disassembly instructions.
Exploded views of critical assemblies.
Adequate system diagrams.
(s) Each pump shall be designed to have a service life of 30 years of which 40
percent shall be actual operation.  There shall be no limit on the number of starts during
the life of the pump.  It shall be assumed that during the life of the pump, parts subject
to unavoidable wear and deterioration (with the exception of packing and rolling contact
bearings) will be replaced at intervals not shorter than 12 years. The parts subject to
wear, deterioration and normally requiring replacement at 12 year intervals during the s ervice
life of the pump (with the exception of packing and rolling contact bearings) shall be de-
signed for a life of 40,000 l atual operating hours, and they shall be identified in appro-
priate drawings and manuals.  The requirements set forth above shall not be construed or
interpreted as a warranty requirement nor otherwise affect the manufacturer's warranty.
3.2.3 Shock and vibration. The boiler feed pump and driver with all appurtenances and controls shall be
capable of passing a shook test in acordanoe with MIL-S-901 as specified in
# Shock mounts (resilient mounts for shook attenuation) shall not be used
unless specified (see 6.1).  When noise attenuation mounts are specified (see 6.1), the pump
shall be designed to pass the specified shock test on the noise attenuation mounts.

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