ARI Eliptix R-20 SM Series, Руководство пользователя

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R-20 SM
2.3. Initial Start-up - The Control Valve
1.
Make sure that the upstream and downstream isolation valves are closed.
2. Turn adjusting screw [ 3 A] clockwise until the screw head touches the pilot's bonnet.
3. Turn adjusting screw [ 5 A] counter-clockwise until the screw head touches the pilot's bonnet.
4.
Turn the
3
-way manual selector ball valve [
4
] to Auto position.
5. Slowly open the upstream isolation valve.
6.
Slightly open the downstream isolation valve.
7. The following is a general description of the Accelerated Pressure Sustaining, Manual Control, Downstream Vent
Application:
This R-
20
SM automatic control valve is a Normally Close Valve (N.C.) activated by the line pressure, which
maintains a minimal preset upstream pressure by releasing excessive pressure to the downstream system. Even
with the valve's large diameter its accelerating pilot ensures efficient and rapid response to line pressure
fluctuations.
When the line upstream pressure rises above the preset point the valve opens to release the excessive pressure to
the downstream system and maintains the upstream pressure at the pre-set level.
When the upstream pressure drops below the setting the valve closes.
The Pressure Sustaining Pilot operation (Pilot #
3
):
When the upstream pressure is higher than the settings, the pilot decreases the internal pressure of the control
chamber by releasing water to the downstream port of the valve, causing the valve's diaphragm to slightly open
and decrease the upstream pressure back to the required settings level.
When the upstream pressure is lower than the settings, the pilot increases the internal pressure of the control
chamber by introducing water to the chamber, causing the valve's diaphragm to slightly close and decrease the
downstream pressure, so the upstream pressure returns back to the required settings level.
The Acceleration Pilot operation (Pilot # 5 ):
When the upstream pressure is higher than the settings, the pilot closes the water passage through port # 2 ,
allowing the Pressure Sustaining Pilot (pilot # 3 ) to decrease the upstream pressure back to the required level.
When the upstream pressure is lower than the settings, the pilot increases the internal pressure of the control
chamber by introducing water to the chamber, and together with the water introduced by the Pressure Sustaining
Pilot (pilot #
3 ) the valve decreases the downstream pressure so the upstream pressure returns back to the
required level.
The Manual Selector operation (Selector #
4 ):
This selector allows the system's operator to set the main valve operation mode to either manually open or to
automatic operation mode.
The Orifice Plate (Plate # 8 ):
The orifice plate is an optional addition for cases where the downstream pressure is expected to be lower than
0.4 bar. The orifice plate builds back pressure across the control valve suitable for the required flow-rate.
8.
Make sure that there is a downstream flow demand.
9. Make sure that the upstream pressure is higher or equal to the required pressure.
10.
Turn the pilot valve’s locking nut (
3
B) counter clockwise, until it touches the adjusting bolt (
3
A) head.
11.
Turn adjusting bolt (
3
A) counter-clockwise until you reach the required upstream pressure.
12. Turn the accelerator adjusting bolt ( 5 A) clockwise until the upstream pressure begins to rise above the required
set point.
13.
Turn the accelerator adjusting bolt (
5
A) counter-clockwise one turn.
14. Turn the locking nuts ( 3 B, 5 B) clockwise until it touches the pilot bonnet. Tighten the nuts carefully.