shall be extended 0.6 m 2 ft lower. Testing shall be inclusive for the
speed involved. Tests shall be made using heads and a suction water
elevation specified in the paragraph CAPACITIES. Test results with this
sump elevation shall meet all specified conditions of capacity, head, and
bkW bhp. Head differentials between adjacent test points shall not exceed
0.9 m 3 ft, but in no case shall less than 10 points be plotted in the
pumping range. If the plot of data indicates a possibility of instability
or a dip in the head-capacity curve, a sufficient number of additional
points on each side of the instability shall be made to clearly define the
head-capacity characteristics.
2.10.1.2
Test Results
Test results shall be plotted to show the total head, static heads, bkW bhp,
and efficiency as ordinates. The results should be plotted against pump
discharge in l/s gpm as the abscissa. Curves shall be plotted showing pump
performance to a scale that will permit reading the head directly to 0.15 m
0.5 ft, capacity to 30 l/s 500 gpm, efficiency to 1 percent, and power
input to 20 bkW 25 bhp. It shall be established that the performance
requirements of these specifications and the warranties under this contract
have been fulfilled. The performance test shall be made with the pump and
motor assembled as an operating unit to simulate field installation unless
otherwise approved in writing by the Contracting Officer. Readings shall
include one point each within 2 percent of the rated total head, minimum
expected head, and maximum expected head. The test shall be conducted in
accordance with accepted practices at full speed; and, unless otherwise
specified, the procedure and instruments used shall conform to HI 2.6.
2.10.2
[Cavitation Test
The net positive suction head required (NPSHR) by the pump shall be
determined by the testing procedures provided in HI 2.6. The Contractor
shall select the test arrangement and procedure, from the choices provided
in HI 2.6, that best suits the Contractor's test facility. NPSHR shall, as
a minimum, be determined for five or more capacities over the total range
of the specified operating conditions. The Contractor shall plot the test
results and define NPSHR as the point where a 3% drop in performance
occurs. The value of NPSHR shall be 0.6 m 2 ft less than the corresponding
net positive suction head available (NPSHA). NPSHA shall be determined
using the temperature of the water at the time the tests are run. The
water elevations specified in paragraph CAPACITIES shall be used to
determine the NPSHA for pumps.]
2.10.3
Instrumentation and Procedures
Each instrument shall be described in detail, giving all data applicable,
such as manufacturer's name, type, model number, certified accuracy,
coefficient, ratios, specific gravity of manometer fluid to be used, and
smallest scale division. When necessary for clarity, a sketch of the
instrument or instrument arrangement shall be included. A fully detailed
narrative description of each proposed method of instrumentation,
procedures to be used, and a sample set of computation shall be included.
The lowest equivalent static head that is obtainable with the testing when
operating along the head-capacity curve of the proposed pump shall be
stated.
2.10.3.1
Head Measurements
Head measurements shall be made using either a direct reading water column,
SECTION 15132A
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