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|  MIL-P-17881D(SHIPS)
4.3.3 .2.3 The unit shall be, mounted on the shock machine or barge" essentially identical
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to the actual shipboard installation. The procuring agency will furnish the supplier a drawing
of the shipboard mounting arrangement. Horizontal pumps when tested in the inclined position
on the medium weight shock machine shall be oriented so that the direction of shock is perpen-
dicular to the axis of pump rotation. The pump shall be in operation during the first and
third blow in each orientation of the medium weight shock machine. The pumps 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 pasts. Other pumps shall be operated at the lowest
rated speed.
4.3.3.2.4 The pump shall be carefully observed during each shock blow and thoroughly
examined visually after each blow. After each blow the unit shall be operated at as close
to maximum rated speed as possible and checked for abnormal noises and vibrations and proper
..
functioning of controls. Turbine driven pumps may be air driven.
4.3.3.2.5
Shock test acceptance criteria:
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There shall be no breakage of parts including mounting bolts.
(a)
There shall be no distortion or derangement of any part which would render
(b)
the unit incapable of performing as specified.
The amplitude of vibration after test at maximum rated speed shall be less
(c)
than twice the amplitude measured at the same speed before the test.
Lubrication to all bearings shall be maintained.
(d)
(e)
Critical dimensions and running clearances shall have been maintained.
There shall be no significant change in the head-capacity curve.
(f)
4.3.3.2.6 Post shock test procedure. The shock tested unit, if it is to be supplied
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under a contract or order and if approved'hall be restored to the as-new condition by
s
replacement of all parts damaged or-distorted beyond the as-new design tolerances. All
rolling contact bearings shall be replaced regardless of condition. The shock tested rolling
contact bearings shall be destroyed. The restored unit shall successfully pass the shop
tests specified in 4.3.1.1, 4.2.1.3(a). and 4.3.1.4 if applicable. The shop test documenta-
tion shall indicate that the unit was subjected to the shock test and subsequently restored,
shop tested and examined. The completed part examination check list shall be supplied and
shall identify the parts which were replaced (such as the bearings) and shall certify that
the unit fully conforms to the specifications for unrestricted service.
#
4.3.3.3 Inclined operation test. Vertical pumps shall be operated for not less than
30 Minutes inclined at an angle from the normal equal to the combination of the maximum
permanent list and trim as specified (see 6.1). Horizontal pumps shall be tested in accord-
ance with the inclined operation tests specified for the driving unit. However, the pump
and driver shall be tested as a unit. The use of air or low pressure steam to test turbine
driven units is not permitted. Operation in the inclined position shall be as close to
rated speed and-capacity as practicable. The performance point shall be indicated in the
test report. The pumps shall meet all specified performance requirements without damage
while operating in the inclined position.
4.3.3.4 Vibration test. When specified (see 6.1) one pump of a quantity of identical
pumps being supplied shall successfully undergo a vibration test in accordance with the
requirements of MIL-STD-167 and as supplemented in the contract or order. The vibration
test need not be repeated on subsequent contracts or orders for pumps of identical design
to those previously tested, provided the previous tests included the frequencies specified
(see 6.1).
4.3.3.4.1 The unit shall be mounted on typical shipboard foundations during the vibra-
tion test or the shipboard mounting arrangement shall be simulated in springmass charac-
teristics except where this mounting arrangement causes the largest test table capacity to
be exceeded. Inability to vibration test the unit because of excessive weight or size shall
not release the supplier from furnishing equipment which can withstand the specified vibra-
tion inputs. Vibration test l eceptanoe criteria shall be in accordance with MIL-STD-167.
#
4.3.3.5 Design evaluation test documentation. The test reports for the design evalua-
tion tests shall
in accordance with good l ngineering practice. The test arrange-
ment and procedure, the test events, the test instruments used, the measured data; and the
effects, results, and observation shall be accurate and complete l nd shall be presented in
a professional manner and in a usable durable form. Distribution of the test reports shall
be as follows;
Two copies to the design review agency.
(a)
Two copies to the procuring l gency.
(b)
Two to one of the following, as applicable:
(c)
Defense Contract Administration Services Region (DCASR).,
Defense Contract Administration Services District (DCASD).
Defense Contract Administration Services Office (DCASO).
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