ha ve one control port plugged. See technical manual
monitor the pressure in the AFFF concentrate piping,
NAVSEA S6435B1MMO010, Solenoid Operated
and one to monitor the firemain pressure. The pressure
Pilot Valve, Model CSM5M3A , for more information
differential between these lines moves the diaphragm
in the control valve. As the AFFF/seawater flow
increases, the firemain sensing line pressure drops, and
the control valve adjusts by forcing more AFFF
concentrate into the proportioner.
VALVE SEA T
Figure 6-11. Hycheck valve.
Figure 6-13. Balancing valve.
Balanced-Pressure Proportioner (Type II)
The Type II balanced-pressure proportioner
c o n c e n t r a t e n e c e s s a r y t o p r o d u c e e ff e c t ive
AFFF/seawater solution over a wide range of flows and
pressures. The system is actuated by activating an
SOPV, electrically or manually. The SOPV will vent the
operating chamber of the hycheck valve and pressurize
the operating chamber of the powertrol valve. The
PORT NO. 2
switch assembly of an SOPV will cause electrical
activation of the pump assembly (positive displacement,
PORT NO. 1
sliding vane, or rotary gear) via the motor controller.
The pump assembly will pressurize the AFFF
Figure 6-12. Solenoid-operated pilot valve (SOPV).
concentrate piping to the demand proportioned and
balancing valve. Water flow through the proportioner
BALANCING VALVE.-- The balancing valve
will move the water float towards the large opening of
the water sleeve, depending on the number of gallons
amount of AFFF concentrate with seawater. The
required for fire fighting. The AFFF concentrate float is
balancing valve is a diaphragm-actuated control valve
directly controlled by the movement of the water float,
that responds to pressure changes between the AFFF
concentrate supply line and the firemain. Two sensing
enters the water stream.
lines are attached to the balancing valve, one to