Xylem AC Fire Pump 8100 Series, Инструкция по установке, эксплуатации и обслуживанию

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AC6102 Rev 0
5
24
Globe valves should not be used, particularly where NPSH is
critical.
The pump must never be throttled by the use of a valve on
the suction side of the pump. Suction valves should be used
only to isolate the pump for maintenance purposes, and
should always be installed in positions to avoid air pockets.
Fig. 18 Suction piping arrangements
7.6.4 Discharge piping
If the discharge piping is short, the pipe diameter can be the
same as the discharge opening. If the piping is long, the pipe
diameter should be one or two sizes larger than the
discharge opening. On long horizontal runs, it is desirable to
maintain an even a grade as possible. Avoid high spots, such
as loops, which will collect air and throttle the system or lead
to erratic pumping.
A slow closing check valve and an isolating gate valve should
be installed in the discharge line. The check valve (triple duty
valve), placed between pump and gate valve, protects the
pump from excessive back pressure, and prevents liquid
from running back through the pump in case of power failure.
The gate valve is used in priming and starting, and when
shutting the pump down.
7.6.5 Bypass Piping
Where the suction supply is of sufficient pressure to be of
material value without the pump, the pump shall be installed
with a bypass.
The bypass pipe diameter shall be at least as large as the
discharge pipe diameter.
7.6.6 Cooling System
NOTICE
This section is only applicable to engine-
driven pump units that have water cooled
heat exchangers.
The cooling water supply for a heat exchanger-type engine
shall be from the discharge of the pump taken off prior to the
pump discharge check valve.
The cooling water flow shall be set based on the maximum
ambient cooling parameters provided by the Engine
Manufacturer.
7.6.7 Exhaust system
NOTICE
This section is only applicable to engine-
driven pump units.
WARNING
Exhaust emissions must be discharged to a
safe point outside the pump room where they
shall not affect persons or endanger buildings.
Operation of an engine without an adequate
exhaust system can result in serious personal
injury.
WARNING
Exhaust pipes are hot and will cause serious
injury if touched.
Each pump engine shall have an independent exhaust
system. The exhaust pipe shall not be any smaller in
diameter than the engine exhaust outlet and shall be as short
as possible.