RP-01638

simultaneously. A head simulation system
was also fabricated to test the performance
of the handpumps under different water heads.
A detailed testing program for the Waterloo
handpump was undertaken (Table 2). In this
table, the orificelpiston area ratios of 12.5,
17.0, and 22.2% represent an opening in the
piston area of eight holes each having a
diameter of 3/8 inch (9.5 mm), 7/16 inch
(11 mm), and 1/2 inch (12.5 mm), respectively.
For each series of tests, the discharge for
10 strokes of the piston was measured using a
bucket and a graduated cylinder. The test
was performed twice and the average value
was recorded. The volumetric efficiency was
defined as actual divided by theoretical
discharge times 100 where the theoretical
discharge is equal to the stroke length
multiplied by the cross-section of the
cylinder.
In addition to the tests on the performance
of handpumps, several other tests were also
conducted.
The mechanical properties - tensile,
compressive, and fatigue strengths - of the
PVC material were determined. A 300-kN
universal testing machine was used for the
tension and compression tests. For the fatigue
test, a servo-pulsator having a capacity of 15 t
was used.
Leakage was tested to check the performance
of the foot valve, which was the
modified foot valve that was installed in
the field.
100 r-
90
80
70
60
1
20
1
30
STROKE RATE (strokes/minute)
1 1 1
40 50 60
Fig. 2. Influence of stroke lengths on volumetric efficiency of Waterloo pumps having 12.5% orifice/piston area ratio. Mater
head, 15 feet (4.57 m); piston diameter, 3 inches (7.5 cm); valve gap, 0.25 inch (0.6 cm); piston foot-valve clearance, 12 inches
(30 cm).)
24