HALE AP, Руководство по эксплуатации и обслуживанию

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Sec I- 2
Introduction
Booster Pumps
The centrifugal pump is preferred by the fire
protection service due to its ability to fully utilize
any positive inlet pressure, reducing the strain
on the pump.
For example, if the required discharge pressure
is 120 PSI (8 BAR), and the inlet pressure is 45
PSI (3 BAR), the pump must only produce the
difference in pressure of 75 PSI (5 BAR). This
contributes to low engine and pump speeds
which reduces wear on the pump. Another
important benefit is the centrifugal pump has
basically only two moving parts; the impeller
and the shaft.
Pump Stages
The number of impellers on a common shaft
determines the number of pump stages. Hale
single-stage booster pumps use a single
impeller to develop the required volume and
pressure. Two stage pumps have two impellers
on a common shaft.
During operation water enters the suction eye of
the impeller. The rotating impeller vanes
develop discharge pressure and direct the water
to the discharge opening. The cutwater is a
wedge that divides the water between the volute
(pump body) and the pump discharge.
There are three models of Hale booster pumps.
(The anticipated use determines which model is
selected.) The AP and CBP booster pumps are
single stage and provide initial attack pump
performance per NFPA 1901 standards. The
2CBP is a two-stage series operation pump, is
used as a high-pressure booster pump.
The available Booster Pump Models and their
flow capacities are shown in Table 1-1.
Figure 1-2: Pump Stages
Figure 1-3: Single-stage Water Flow
Model Type Capacity Pressure
AP
Single-Stage High
Volume Attack Pump
100 to 700 GPM (379 to
2650 LPM) NFPA1901 Rated
@250 to 500 GPM (946 to
1893 LPM)
100 to 350 PSI
(7 to 24 BAR)
CBP
Single-Stage High
Volume
Attack/Booster Pump
50 to 400 GPM (189 to 1514
LPM) NFPA1901 Rated
@250 GPM (946 LPM)
100 to 400 PSI
(7 to 28 BAR)
2CBP
Two-Stage High
Pressure Booster
Pump
20 to 100 GPM (76 to 379
LPM)
300 to 1000 PSI
(21 to 69 BAR)
Table 1-1: Booster Pump Models and Capacities