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|  MIL-P-17840C(SH)
3.2.2.4 In-order to ensure comparability of parts, calculations of the
worst-case cumulative effect of dimensions- and tolerances for parts and location
shall be provided. These calculations shall demonstrate:
(a) There will be no interferences between rotating and stationary
parts as-assembled.
(b) There will be no interference between rotating and stationary
parts, and hence no reduction in life of wearing parts, when
these worst-case cumulative effects are combined with
operational, environmental, and thermal loading.
3.2.3 Shock and vibration.
3.2.3.1 Pumps and drivers, all appurtenances and controls shall pass a
shock test in accordance with MIL-S-901, grade A, as specified in 4.6.6.
3.2.3.2 Shock mounts (resilient mounts for shock attenuation) shall not
be used. All pumps shall pass the specified shock test solidly mounted,
whether or not noise attenuation mounts are specified for mounting the- unit in
the ship.
3.2.3.3 Bolts designed to be stressed in shear shall be installed in
holes with a minimum of clearance. Hole diameters shall be not more than 1/32
inch larger than the bolts for sizes up to and including 3/4 inch, and no more
than 1/16 inch larger than bolts of greater than 3/4 inch size. Mounting bolts
for fastening the equipment shall conform to grade 2 or better of MIL-S-1222.
3.2.3.4 Pumps shall not be damaged or caused to malfunction by either the
environmental vibrations or by internally excited vibrations. Units furnished
under this specification shall be tested to meet the requirements of MIL-STD-
167-1, type I and II (see 6.2.1).
3.2.4 Alignment.
3.2.4.1 The design of the pump units shall be such as to permit handling,
shipment, and Installation of the units on board ship without disturbing align-
ment and such that the normal distortion, weaving, or vibration of the
supporting structures on board ships cannot cause fracture or appreciable
distortion.
3.2.4.2 Alignment between separate components of a unit shall be maintained
by means of keyways, rabbeted or tongue and groove joints, fitted bolts, or
other means. Parts manufactured to the same drawings shall be interchangeable.
3.2.4.3 In no case shall a piece of equipment be rigidly supported from
more than one plane.
3.2.4.4 The alignment shall be rechecked by the installing activity after
final installation. This can be done by rotating the shaft by hand at least
three revolutions.
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