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|  MIL-P-17881D (SHIPS)
(c) Operate the electric motor-driven unit for a minimum of 1 minute in
reverse rotation at maximum rated speed.
Acceptance criteria: The unit shall not be damaged by the reverse rotation test. Con-
formance to hydraulic and noise requirements shall be demonstrated subsequent to the reverse
rotation test.
4.3.1.4 Noise test. When required (see 6.1), a noise test shall be conducted and re-
#
ported in accordance with MIL-STD-740. The noise test stand details, instrumentation, and
testing technique shall be submitted by the supplier for review by the design review agency
prior to test commencement. Airborne noise tests shall be conducted on the lead unit only
on each contract or order.
Acceptance criteria:
The unit shall meet the noise level limits specified (see 6.1).
4.3.1.5 Radiographic inspection. Radiographic, magnetic particle and liquid penetrant
inspection of castings and weldments shall comply with MIL-STD-278 and MIL-STD-271. Pump
casings shall be radiographed in those areas which act as pressure boundaries subject to
pressures of 550 pounds per square inch gage (psig) and above.
4.3.2 Performance evaluation tests. One pump of each type, design and size on each
#
contract or order, complete with driver and all appurtenances and controls, shall suc-
cessfully undergo the performance evaluation tests to establish the complete pump perform-
ance map and to ascertain compliance with the specified performance requirements. when pumps
of identical type, design and size are being produced under two or more contracts within a
2 year period, only one series of performance evaluation tests shall be required for that
production run. The following tests shall comprise the performance evaluatation tests.
(a) Performance test (see 4.3.2.1).
(b) Mechanical shaft seal and alignment procedure (see 4.3.2.2).
(c) Thrust test (if specified in 6.1) (see 4.3.2.3).
#
4.3.2.1 Performance test. The performance test shall be conducted, recorded and
reported in accordance with the requirements for the shop test specified in 4.3.1.3, except
that the use of a substitute driver shall not be permitted and that, in addition to the head-
capacity curve at maximum rated speed, a full performance map shall be established. The
proposed test procedure for this test shall be submitted to the design review agency, for
approval approximately at the time of drawing submittal. Test data shall be converted to
specified operating conditions for plotting of all performance curves. The performance
curves shall be determined at maximum and minimum operating speed for variable speed pumps
and at each operating speed for multi-speed pumps. The following curves shall be established;
(a)
Capacity
versus
total head.
(b)
Capacity
versus
pump efficiency.
(c)
Capacity
versus
brake horsepower.
(d)
Capacity
versus
steam consumption or electric power input.-
(e)
Capacity
versus
net positive suction head.
-
Acceptance criteria: The acceptance criteria specified in 4.3.1.3 (a) and (b) shall be
met. The performance map shall exhibit the specified pump performance characteristics and
meet the steam rate requirements where applicable. All controls and safety devices shall
function as intended throughout the full operating ranges of capacity and speed.
#
the technical manual. The mechanical seals shall be run in and the pump operated at maximum
rated speed with the fluid pumped at maximum operating temperature. The tests shall verify
seal installation and back-up packing installation procedures. Stuffing box leakage, if
any, shall be determined. The dynamic balance shall be checked by use of a vibration
indicator (see 4.3.1.2).
Acceptance criteria: Mechanical seal leakage shall not exceed 5 drops per minute. The
vibrations shall not exceed the limits specified in 4.3.1.2.
#
4.3.2.3 Thrust test. When required (see 6.1), the pump and driver shall be operated
in accordance with the requirements for the shop test specified in 4.3.1.3 at the maximum
operating speed. The magnitude and direction of axial thrust loading at the thrust bearing
shall be measured. This test may be conducted concurrent with the performance test specified
in 4.3.2.1. A curve of thrust versus capacity shall be l stablished. The effect on axial
thrust of operating conditions, such as temperature and suction pressure, shall be determined
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