Watts M1115-2 - Manual

12541 Gulf Freeway • Houston, Texas 77034 • (Ph) 713.943.0688 • (Fx) 713.944.9445 • www.watts.com
○ X – Isolation Cocks
○ FC – Flo-Clean Strainer
○ Y – Y-Strainer (Replaces Flo-Clean)
○ ACS – Adjustable Closing Speed
(Replaces Fixed Orifice)
○ AOS – Adjustable Opening Speed
○ P – Position Indicator
○ L – Limit Switch
05/09
M
ustang
s
eries
Standard Components
Options & Accessories
(3)
(3)
(3)
(2)
(2)
(1)
(1)
Standard 3” & Smaller
Standard 4” & Larger
Optional All Sizes (3)
(2)
(1)
Schematic
910 link
1
X
X X
Y/FC
P/L
3
4
2
CLOSES VALVE
OPENS VALVE
FLOW
(AOS)
M115-2 (Globe)
M1115-2 (Angle)
Operations
PRESSURE REDUCING CONTROL VALVE
WITH PRESSURE SUSTAINING FEATURE
• Throttles to reduce high upstream pressure to constant
lower downstream pressure
• Throttles to maintain minimum upstream pressure
• Reducing and Sustaining setpoints are separately
adjustable
1 – Main Valve (Single Chamber)
2 – Pressure Reducing Control
3 – Pressure Sustaining Control
4 – Fixed Orifice
The Combination Pressure Reducing and Pressure Sustaining Control Valve is designed to automatically
reduce a fluctuating higher upstream pressure to a constant lower downstream pressure regardless of
varying flow rates, and will throttle to sustain a minimum upstream pressure. It is controlled by a normally
open, pressure reducing pilot designed to: 1) Open (allowing fluid out of the main valve cover chamber)
when downstream pressure is below the adjustable setpoint, and 2) Close (allowing fluid to fill the main valve
cover chamber) when downstream pressure is above the adjustable setpoint. A decrease in downstream
pressure causes the valve to modulate toward an open position, raising downstream pressure. An increase
in downstream pressure causes the valve to modulate toward a closed position, lowering downstream
pressure.
The normally closed sustaining pilot remains open when upstream pressure is above the adjustable setpoint,
and modulates toward a closed position if upstream pressure falls below the setpoint. As the sustaining pilot
closes, fluid is directed into the main valve cover chamber, allowing the valve to modulate toward a closed
position, raising upstream pressure. Normal pressure reducing operation resumes when upstream pressure
is above the sustaining pilot setpoint, and downstream pressure is below the reducing pilot setpoint.