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|  MIL-P-18682D(SH)
(g) Components subject to attack from corrosion, erosion,
cavitation, etc. shall be in a condition commensurate with
500 hours of service.
(h) Wear rates for wearing parts, critical for proper operation,
shall show a rate of wear for the test period that shall be
consistent with the specified design life requirements.
(i) No failures shall have occurred throughout the 500-hour test.
4.6.7.1.6 Post endurance test procedures. The unit subjected to the
500-hour endurance test shall be restored to the as-new condition by replace-
ment of all parts worn beyond the as-new design tolerances. The restored unit
shall successfully pass the tests specified in 4.6.1, 4.6.3(a), and 4.6.4, if
applicable. The quality conformance test documentation shall indicate that
the unit was subjected to the endurance test and subsequently restored, tested,
and that it shall be certified as fully conforming to the specification for
unrestricted service.
4.6.7.2 Shock test. The pump shall undergo a shock test to ascertain
that the pump has the necessary shock resistance. The shock test shall be
performed in accordance with MIL-S-901, grade A, and the specific shock test
requirements (see 6.2.1).
4.6.7.2.1 Before and after shock test, the pump and driver and other
components susceptible to internal derangement shall be disassembled to the
extent necessary and the critical dimensions and running clearances measured,
calculated, and recorded. During this disassembly, the critical components
and assemblies subject to shock damage and derangement shall be identified and
listed in the Inspection record and after completion of the test, the condition
of each component and assembly shall be determined and recorded. Shafts,
impellers, and turbine rotors, motor rotors, and reduction gears shall be
inspected by one of the applicable non-destructive test procedures, other than
radiography, specified in MIL-STD-271.
4.6.7.2.2 Before and after the shock test, tests in accordance with 4.6.3
shall be performed to determine the changes in performance characteristics of
the pump. Vibration measurements shall be taken at the bearing caps or housings
of the pump and driver at equal speeds during the initial and final capacity
test to determine the changes in mechanical operation.
4.6.7.2.3 The unit shall be mounted on the shock machine or barge essenti-
ally identical to the actual shipboard installation. The contracting activity
will furnish the contractor a drawing of the shipboard mounting arrangement and
foundation's stiffness. Horizontal pumps, when tested in the inclined position
on the medium weight shock machine, shall be oriented so that the direction of
shock is perpendicular to the axis of the pump rotation. The pump shall be in
operation during the first, third, and fifth blows of the shock test on the
floating barge. Variable speed pumps shall be operated at the minimum speed and
pressure required to insure lubrication of bearings and wearing parts. Other
pumps shall be operated at the lowest rated speed.
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