(f) Indicated torque is the torque as indicated by a torque-
(g) Horsepower input is ind. torque x base r. p.m.
(h) Horsepower output is corr. g. p. m. x 0.000583 x p. s. L
(i) Overall efficiency is the horsepower output divided by
the horsepower input.
4.6 Test conditions. -
4.6.1 Tests specified hereinafter will be based on:
(a) A sample constant or variable delivery pump loaded by
throttling the discharge port, using a heat exchanger,
where necessary, to maintain proper operating tempera-
ture (see 3.3.10) or,
(b) A sample matched constant or variable delivery pump and
hydraulic motor operating as a transmission and loaded
by m cans of a dynamometer. Under either condition,
the pumps shall be driven at designed speed and delivery
rate through a torquemeter by a suitable electric motor.
4.6.2 Tests shall be performed in the order specified in 4.10.
4 . 6 . 3 During each of the tests for classes I, II, III, and IV pumps, the
s uction oil temperature shall be maintained as near constant as practicable at
For class V pumps the suction oil temperature shall
be maintained at
These temperatures shall be maintained through all
tests, except those specified in 4.10.11 and 4.10.12. Each test shall be con-
ducted at the following suction pressures: (1) 20 p.s.i. (2) 0 inch Hg.
(3) 10 inch Hg.
4.6.4 Oil temperatures shall be measured by means of a thermometer
which has been securely fastened in direct contact with the main pressure pipe
near the pump. Additional test thermometers may be secured at other locations
in the hydraulic circuit as desired.
4.6.5 Measurement of fluid flow shall be accomplished by means of a
positive displacement meter with an accuracy of at least 99 percent or by
appropriate weighing equipment.