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|  MIL-P-17945A(SH)
4.3.2 Shop test,
4.3.2.1 Pump casings and pressure tank, where funished, shall be tested hydrostatically
to a gage pressure one and one-half times the maximum discharge pressure or total head, which-
ever is greater, but in no case to less than SO pounds per square inch
4.3.2.2 Pumps driven by d.c. motors shall be tested at full load at 25 percent above
designed maximum operating speed by a continuous nonstop run of at least 30 minutes. This
test shall be conducted to check for smoothness of operation of pump and motor unit. Pumps
driven by a.c. motors shall be tested for smoothness of operation at full load and full speed.
4.3.3 Shock.
4.3.3.1 Unless otherwise specified in the contract or order (see 6.2.1), one complete
pumping unit of each type, and size shall be subject to the HI shock tests specified in MIL-
S-901 for type A, shock-proofness, class III equipment, except as otherwise required herein.
4.3.3.2 When the shock tests are on a medium-weight shock machine, three blows shall be
applied with the pumps mounted in its normal orientation; three blows shall be applied with
the pump inclined 30 degrees about one horizontal axis and three blows shall be applied with
the pump inclined 30 degrees about the other horizontal axis for a total of nine blows (three
blows in each of three groups in accordance with MIL-S-901). The pump shall be tested running
and at standstill on alternate blows. Pumps need not be running at rated speed or pumping
at rated capacity during the shock test.
4.3.3.3 Equipment exactly duplicating that previously shock tested as required by
4.3.3.1 and 4.3.3.2 and accepted need not be retested except when evidence of low shock
resistance develops in installed units. The command or agency concerned will initiate action
for correction of deficiencies and reserves the right to require additional shock tests.
4.3.3.4 Pump units shall be shock tested with drivers unless otherwise approved by
NAVSEC. Flexible-coupled pumps shock tested with one driver will not be required to be
shock tested again when supplied with a different drive
f equal or lesser weight, subject
to concurrence of the command or agency concerned. In the vent drivers are not shock tested
with the pump unit, the drivers will have been or will be shock tested in accordance with
MIL-S-901 either separately or with another driver unit.
4.3.3.5 A pump unit shall be considered to have failed to pass the shock tests in the
event of any of the following:
(a) Breakage of any parts, including mounting bolts.
(b) Appreciable distortion, deformation, or dislocation of any part, such as
shaft, mounting feet or bearings.
(c) A mechanical unbalance of more than two times the amplitude of unbalance
measured prior to tests at rated speed or more than that permitted by the
specifications for the driver. The amplitude of unbalance both before and
after the shock tests and the speed at which measured shall be recorded in
the shock test report (see 4.6).
4.3.3.6 Where a manufacturer is unable to conduct these tests at his own plant, he
may arrange to have them conducted at a commercial or Government laboratory equipped to
conduct tests. Where shock tests are conducted at a Government laboratory, copies of the
applicable drawings shall accompany the units.
4.3.3.7 Pump units which have been subjected to the HI shock test and have failed to
conform to the requirements will not be acceptable.
4.3.3.8 Pump units which have been subjected to the HI shock test and have successfully
passed this test shall be considered acceptable for such service as the command or agency
concerned may authorize. Such equipment shall be reconditioned by the manufacturer as
follows:
Minor deformations of mounting flanges shall be corrected.
(a)
(b)
Minor deformations affecting alinement shall be corrected.
(c)
All bearings shall be replaced.
(d)
Each part shall be carefully examined by the manufacturer end any part
which he considers substandard shall be replaced.
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