HALE Silencer AP Series, Инструкция по установке, эксплуатации и техническому обслуживанию

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❑
Introduction
20
Section 2: Introduction
Hale Products, Inc., May 2006, Rev-B
Transferring Between Volume and Pressur Operation
Transferring between volume and pressure operation is evidenced by a
metallic click, which results from the check valves closing. If the click is too
loud or, perhaps, somewhat violent, the pumping pressure is too high for
switching. In this case, you should ease back on the engine throttle.
Switching between volume and pressure operation is generally governed by
prevailing fire department policy. However, there are some general guide-
lines if your fire department does not have an established policy:
1. The pump should be operated so that engine speed is within its
best operating range.
2. Transfer to volume (parallel) operation if the pump has to dis-
charge more than 50 percent of its rated capacity. Be certain to
warn everyone involved before switching between volume and
pressure operation.
3. Reduce the pump pressure to 50-60 PSI (3-4 BAR) before
switching. The engine speed should especially be reduced
when switching from volume to pressure operation with hand
held hoses in use.
2.4 PUMP DRIVES
Hale pumps produce the volumes and pressures shown on their perfor-
mance curves. However, maximum pump performance is sometimes lim-
ited by the power capacity and speed limits of the engine, transmission, and
PTO, as applicable. (See Figure 2-6: “Pump / Engine Rotation.”)
Three common pump drives are
used:
❑
Split-shaft gearbox from the
apparatus drive shaft.
❑
Operation from a Power Take-
Off (PTO) from the truck trans-
mission or drive train.
❑
A stand-alone drive with sepa-
rate engine (auxiliary engine).
Note: Also see Plate #843A “Vehi-
cle Mounted Pump Applications”
located at the back of this manual.
Figure 2-6: Pump / Engine Rotation