Hale RSD - Manual (Page 56)

❑ Preventive Maintenance
56 RSD Series Single-Stage PTO Pumps
p/n: 029-0020-92-0
Pumpers should be tested from draft at not over a 10’ (3 meters) lift with 20’ (6
meters) of suction hose. Pumpers rated at 1,500 GPM and above often require
two separate 20’ lengths of suction hose and a lower lift height.
Use smooth bore test nozzles of accurate size with the pitot gauge. The vol-
ume pumped is then determined by reference to discharge tables for smooth
nozzles. Preferably, nozzles will be used on a Siamese deluge gun for greatest
accuracy. A stream straightener, just upstream of the nozzle is advisable.
REFER TO LOCAL PROCEDURES FOR PUMP TESTING PROCEDURES
AND PRACTICES AS WELL AS APPLICABLE NFPA STANDARDS.
For Pitot Gauge accuracy, the nozzle pressures should be between 30 and 85
PSIG (2.1 and 6.0 BAR). Also see “Appendix E: Nozzle Size vs. Pressure” on
page 119 at the back of this manual.
The amount of discharge hose required for the service tests is dependent on
the flow requirements and capacity test point. Provide adequate hose to dis-
charge the rated capacity with a flow velocity less that 35 ft./sec.
Also see “Appendix D: Hose Friction Loss” on page 117 at the back of this
manual.
Since NFPA standards specify both GPM and pressure, it is usually necessary
to restrict the flow somewhat to build up the pump pressure. In normal pump-
ing, this restriction would be caused by the friction loss in the lines. It is com-
mon practice to gate the discharge valves as required to maintain pressure.
Notes:
● For 750 GPM (2,839 LPM) test, two 2-1/2” (64 mm) lines should be laid from the
pumper to the nozzle
● For 1,000 GPM (3,785 LPM) test, three lines are required
● For the 1,250 (4,731 LPM) and 1,500 GPM (5,677 LPM) tests, four or more lines
are required between the pumper and the nozzle.
Because deluge guns are not always available, other hose layouts may be used, such
as one, 2-1/2” (64 mm) line to a 1-3/8” (35 mm) nozzle for 500 GPM (1,892 LPM).
Generally, the nozzle used on one, 2-1/2” line should not be larger than 1-1/2” (38
mm) for accuracy in measuring GPM (LPM).
Another alternative when a deluge gun is not available consists of a 1-1/4” (32 mm)
nozzle on one and a 1-1/2” (38 mm) nozzle on the other to pass 1,000 GPM (3,785
LPM). The sum of the flow from both nozzles is the GPM (LPM) delivered by the
pump. For good pitot gauge accuracy, the nozzle pressures should be between 30
and 85 PSIG (2.1 and 5.8 BAR).