Innovative Automatic
Control Valves
Hydraulic Control Valves
for Water Works & Irrigation
1
Ooval valves are self-acting, pilot operated
diaphragm control valves that provide remarkable
benefits and unparalleled value in both basic on/off
operations and sophisticated functions - controlling
pressures, levels and flows.
The valves are hydraulically operated automatic valves that
combine the simplicity and reliability of a diaphragm valve
with the control capabilities of a pilot operated, self-acting
regulator. The unique design of the valve optimizes both flow
capacity and control. The revolutionary body design provides
a streamlined flow path and incorporates the multi-functional
oval diaphragm in an efficient hydrodynamic design. This
design provides superior resistance to cavitation and erosion
and insures smooth flow without turbulence or noise.
One basic valve…
At the heart of the valve lies the unique oval diaphragm, which
is capable of opening and closing at 0.4 bar, as well as normal
operation up to 16 bar. The valve’s incomparable versatility
offers pressure reduction over a wide range of flows. Other
valves have limitations and require special accessories or
different diaphragms to achieve optimum results. Ooval valve’s
greater range of flows overcome these restrictions, providing
immediate solutions for general water supply and irrigation.
Ooval valves are used in water works,
agricultural, landscape, industrial, mining
and wastewater applications.
2
Consistent Performance
• Reliable trouble free valve operation; controlled,
smooth and accurate closing and opening at low
flows with drip-tight sealing.
• Extremely stable and accurate control during
shut-off and regulation; provides versatile
rangeability and low flow control.
• High flow capacity and very low head loss
resulting from the innovatively designed body
and flow path.
• Positive drip-tight sealing is guaranteed by the
oval diaphragm’s design and its resilient sealing
surface.
• Easy inline maintenance is provided by top
entry design.
• Rugged, high quality construction meets
applicable engineering standards.
• Proven pressure, flow and level regulation pilots,
electric solenoids and control accessories.
one valve spring…
one diaphragm…for all
applications. Provides
operational flexibility;
no need for different
diaphragms and springs
to meet varying pressures
or flow conditions.
3
Dependable Control
Design based on simplicity. Engineered to perform under the most demanding
conditions. Each valve assures a closing close, which minimizes water hammer and
absorbs the pressure shock caused by system shut-off.
Open Mode
High Efficiency – Low Head Loss
The flow path is wide and clear of obstructions for superior hydraulic performance and
lower pressure loss.
Pressure Reduction Over A Wide Flow Range
Ooval valves are capable of reducing pressures at extremely low flow rates, as well as
high flow rates, due to the multi-functional oval diaphragm. The same diaphragm can
open, close, and reduce pressures down to 0.4 bar.
Closed Mode
Protective Coating
The interior and exterior of the valve are treated with a pliable electrostatic spray
polyester coating that will not chip, is rust resistant, and stands up to sun, salt
and other corrosive elements. The coating process includes pre-treatment blasting,
electrostatic spraying of polyester, and oven-heated curing to bond the paint.
Easy Maintenance
Ooval valves require minimal maintenance. The valve never needs to be removed from
the line. The bonnet is easily removed revealing the diaphragm and spring that may
require upkeep.
Diaphragm
Hydraulic Accessories
Ooval offers a complete line of multi-purpose pilots and accessories. By combining
Ooval valves with precise hydraulic accessories, solutions to both common and more
complex valve requirements are readily attained. The plastic pilot in particular, has
new innovative features not available in similar type products; such as larger passages
for quick reaction time and non-breakable directional assembly.
All Ooval valves can be controlled by 3-way pilots or 2-way control loops.
Standard valves can be controlled manually or by Electric, Pressure Reducing, Pressure
Sustaining/Relief, Hydraulic Relay, and Quick Reacting Pressure Relief.
Additional valve control features include Surge Anticipating-Quick Relief, Pump Control,
Flow Rate Control, Two Stage Opening, Float Control, and Check Valve options.
4
Technical Specifications
Flow Chart
1”+1½”
1½S”
Valve Specifications
Body
3R”+2”
2A”
4A”
6” 8” 10”
Bonnet
Diaphragm
Spring
Seat
Bolts
Estimated
12”
Cast Iron/ASTM A 45 CI S25 A
Cast Bronze/BS 1400 LG
Ductile Iron/ASTM A-536
Same as above
Natural Rubber
Stainless Steel
Acetal
Steel Cobalt Coated
3N” 3S”
2000
4500
8800
Valve Dimensions
Straight
Angle
Inch
1"
1.5"N
1.5"S
2"
2"
323"
3"
3"
3"
3"S
3"S
4"
4"
6"
6"
8"
10"
12"
2"
323"
3"
3"
3"
3S"
3S"
4"
4"
Size
mm
25
40
40
50
50
80-50-80
80
80
80
80
80
100
100
150
150
200
250
300
50
80-50-80
80
80
80
80
80
100
100
Material
cast iron
cast iron
cast iron
Bronze
cast iron
cast iron
cast iron
cast iron
cast iron
cast iron
cast iron
cast iron
cast iron
Ductile Iron
Ductile Iron
Ductile Iron
Ductile Iron
Ductile Iron
cast iron
Cast iron
cast iron
cast iron
cast iron
cast iron
cast iron
cast iron
cast iron
Connections
threaded
threaded
threaded
threaded
threaded
threaded
threaded
Flanged
Grooved
threaded
Flanged
Grooved
flanged
Grooved
Flanged
Flanged
Flanged
Flanged
threaded
threaded
threaded
Flanged
Grooved
threaded
Flanged
Grooved
Flanged
Length (L)
Inch
mm
5
127
5.51
140
6.9
176
7.32
186
7.32
186
9.88
251
10
254
10
254
10
254
12.48
317
10
254
12.01
305
12.01
305
17.17
436
15.98
406
20.5
521
24.92
633
29.9
753
6.34
161
8.11
206
9.64
245
10.39
264
8.61
218.7
9.64
245
10.39
264
9.37
238
11.73
298
Height (H)
Inch
mm
2.16
55
2.76
70
3.11
79
3.35
85
3.29
84
4.37
111
5
127
7.87
200
4.52
115
5.73
146
7.89
201
5.64
143
8.7
221
8.36
212.31
11.38
289
13.5
343
15.98
406
18.9
480
6.34
161
8.11
206
9.64
245
10.39
264
8.61
218.7
9.64
245
10.39
264
9.37
238
11.73
298
Width (W)
Inch
mm
3.07
78
3.07
78
4.96
126
4.96
126
4.96
126
4.96
126
6.4
162.4
7.87
200
6.4
162.4
8.35
212
8.35
212
8.34
212
8.7
211
11.81
300
11.8
300
13.5
343
20.7
527
20.7
527
4.96
126
4.96
126
8.31
211
8.31
211
6.34
161.2
8.31
211
8.31
211
8.31
211
8.31
211
Weight
Lbs
Kg
1.98
0.9
2.65
1.2
5.94
2.7
6.61
3
6.61
3
10.8
4.9
16.7
7.6
29.3
13.3
13
5.93
28.44
12.9
36.82
16.7
26.45
12
47.8
21.7
53.35
24.2
84.9
38.5
114.7
52
274
124.5
337
153.5
7.1
3.2
12.8
5.65
29.8
13.5
38.5
17.45
12.8
5.8
29.8
13.5
38.5
17.45
27.77
12.6
47.8
21.7
Recommended Working Conditions
Nominal Diameter
Inch
2”
323”
3”
3S”
4”
6”
8”
mm
50
80-50-80
80
80
100
150
200
Inlet Pressure, PSI & Bar
Minimum
Maximum
Bar
PSI Bar PSI
0.4
16
228
6
0.4
16
228
6
0.4
16
228
6
0.4
16
228
6
0.4
16
228
6
0.4
16
228
6
0.4
16
228
6
Flow Rate, GPM & (m3/h)
Minimum
Maximum
GPM (m3/h) GPM (m3/h)
0.5
40
175
2.2
0.5
55
240
2.2
0.5
80
350
2.2
0.5
105
460
2.2
0.5
165
720
2.2
0.5
1630 370
2.2
0.5
1938 440
2.2
Fully Opened Valve
*Cv Factor
109
109
195
307
312
862
885
*Kv Factor
95
95
160
260
270
740
760
Cv=Q/√ΔP Where Q=Flow Rate (GPM), ΔP=Head loss across the valve (PSI)
Kv=Q/√ΔP Where Q=Flow Rate (M3/h), ΔP=Head loss across the valve (BARI)
5
Pilot Specifications
P-21
P-22
P-23
P-24
P-31
P-32
P-33
P-36
P-22
P-24
2-way Pressure Reducing metal pilot. 7-230 PSI (0.5-16 bar)
2-way Pressure Sustaining metal pilot. 7-230 PSI (0.5-16 bar)
2-way Quick Relief metal pilot. 7-230 PSI (0.5-16 bar)
Altitude metal pilot. 7-230 PSI (0.5-16 bar)
3-way Pressure Reducing/Sustaining plastic pilot. 7-145 PSI (0.5-10 bar)
3-way differential pressure plastic pilot. 7-145 PSI (0.5-10 bar)
3-way Pressure Reducing/Sustaining Metal pilot. 7-230 PSI (0.5-16 bar)
3-way differential pressure metal pilot. 7-145 PSI (0.5-10 bar)
P-21
P-31
Principal Operation 3-way Pressure Reducing
Port
1
2
3
4
Pressure Reducing
Sensing / Downstream
Vent
Control Chamber
Pressure / Upstream
Pressure Sustaining
Sensing / Upstream
Pressure / Upstream
Control Chamber
Vent
Principal Operation 2-way Pressure Reducing
Port
1 or 2
3
4
6
Pressure Reducing
Sensing / Downstream
Pressure / Upstream
Control Chamber
Pressure Reducing Valve
Applications
Ooval reducing configurations for general water
supply systems with medium pressure rating.
The plastic pilot model is best for irrigation and
low-pressure applications. The plastic materials
and straightforward design provide high
corrosion resistance and cost-effective prices.
The 2-way pilot configuration, together with the
unique diaphragm, enables smooth and precise
pressure control.
Use Ooval valve for domestic, water works,
and filtration networks.
Description
Ooval valves are piloted hydraulic valves activated
by line pressure. The pilot valve has a spring-loaded
diaphragm that is sensitive to downstream pressure.
The pilot’s spring is preset to the desired reduced
pressure. The pilot valve maintains a constant
downstream pressure by gradually opening and
closing the Ooval valves at any flow rate.
Available Models
• 3-way Pressure Reducing Valve for sizes 2”-8”
with pressure ratings up to 145 PSI (10 bar).
• 2 and 3-way Pressure Reducing Valve with
pressure rating up to 232 PSI (16 bar).
Adjustment
• Adjust the reduced pressure set point with the
adjusting screw on the pilot.
Function
The Ooval Pressure Reducing Valve is activated
by line pressure and controlled by the pilot valve.
The pilot includes a spring-loaded diaphragm
that is exposed to the downstream pressure. The
displacement of the membrane due to downstream
fluctuation defines the flow direction inside the
pilot. When the downstream pressure is lower than
desired, the valve is automatically directed to open.
In the reverse case, it is automatically directed to
close. When line pressure is inserted into the control
chamber of the valve (above its diaphragm) the
valve closes. When the control chamber drains, the
valve opens as a result of the line pressure from
below its diaphragm. In two-way configurations, the
control chamber drains downstream, enabling faster
reaction time and gradual opening without water
discharge.
Control Mode –
3-way Plastic/Metal Pilot
Control Mode –
2-way Pilot
Manual: Use the three-way selector to close
or open the valve by turning the handle to C
(closed) or O (open) positions.
Automatic: Position the three-way
selector handle to A (automatic). When the
downstream pressure is lower than that of
the pilot spring, the valve’s control chamber
drains via ports 3 and 2 of the pilot to open
the valve. When the downstream pressure is
too high, the pilot diaphragm moves upward
allowing ports 3 and 4 to connect, thus
permitting line pressure to close the valve.
Manual: To open the Ooval valve, open
isolation valves 1 and 2. To close the Ooval
valve, close the downstream isolation valve.
Automatic: When the downstream
pressure is lower than that of the pilot
spring, the control chamber drains
downstream and the valve opens. In this
case, there is a connection between port
3 (inlet upstream), port 1 or 2 (outlet
downstream) and the control chamber.
When the downstream pressure rises above
the preset spring load, the pilot’s diaphragm
is forced upward, closing port 1 or 2. The
valve then begins closing and downstream
pressure decreases.
In three-way configurations, the control
chamber drains out to atmosphere,
permitting the valve to open entirely.
7
Pressure Sustaining / Relief Valve
Applications
Use the pressure sustaining/relief valve to
maintain constant upstream pressure and to
avoid undesirable high-pressure situations.
This protection is required for most irrigation
systems, domestic and industrial utilities, and
for general water supply systems. The 3-way
plastic pilot model provides high resistance to
corrosion at a cost effective price. It is best for
irrigation, filtration manifolds, water treatment
circulation and low-pressure domestic
applications. The 2-way pilot command provides
smooth and precise pressure control.
Description
The pilot valve has a spring-loaded diaphragm
that is exposed to upstream pressure. The valve
is normally closed. With Pressure Relief Valves,
only when the line pressure rises above a preset
point does the valve open to reduce the excessive
upstream pressure. The excess pressure is released
off-line. Pressure Sustaining Valves reduce the
excessive downstream pressure without causing
surge hazards. When the line pressure drops
beneath the desired point, the valve closes.
Available Models
• 3-way plastic piloted pressure sustaining/relief
valve for sizes 2”-8” with pressure rating up to 145
PSI (10 bars).
• 2 and 3-way Pressure Sustaining/Relief Valve with
pressure rating up to 232 PSI (16 bars).
Adjustment
• Adjust the sustained pressure with the adjustment
screw on the pilot.
Function
The Pressure Sustaining/ Relief Valve is activated
by the line pressure and controlled by a pilot valve.
A sustained pressure is preset by adjusting the
pilot retaining spring. The pilot is connected to line
pressure (upstream). The displacement of the pilot’s
spring-loaded diaphragm due to upstream pressure
defines the flow direction inside the pilot. When the
upstream pressure is higher than the set point, the
valve is piloted to open. Otherwise the valve remains
closed, maintaining the upstream pressure. The
excess line pressure is relieved downstream. In 3way pilot configurations, the valve control chamber
drains out, enabling the valve to open fully. In 2-way
pilot configurations, the control chamber drains
downstream, enabling faster reaction time and
gradual closure without water discharge.
8
Control Mode –
3-way Plastic/Metal Pilot
Control Mode –
2-way Pilot
Manual: Use the three-way selector to close
or open the valve by turning the handle to C
(closed) or O (open) positions.
Automatic: Position the three-way selector
handle to A (automatic). When the upstream
pressure is low, the pilot’s diaphragm is in its
lowest position. The valve’s control chamber
is exposed to line pressure through ports
2-3 of the pilot. The valve closes to sustain
the upstream pressure. When the upstream
pressure is higher than preset, the pressure
overcomes the pilot’s spring and forces the
pilot’s diaphragm to move upward. The
connection between ports 3-4 opens and
port 2 closes. The control chamber drains
and the valve opens to relieve the excessive
pressure downstream.
In 3-way configurations, the control
chamber drains out to atmosphere,
permitting the valve to fully open.
Manual: To open the valve, open isolation
valves 1 and 2. To close the valve, close the
downstream isolation valve. The upstream
isolation valve should remain open.
Automatic: When the upstream pressure
is lower than that of the sustained pressure
set point, the valve’s control chamber is
connected to the line. This connection occurs
through ports 1 or 2 (inlet upstream) and
port 3. The valve closes until the desired
upstream pressure is achieved. When the
upstream pressure rises above the set point,
the pilot’s diaphragm is forced upward.
Port 5 (outlet downstream) opens and the
control chamber of the Ooval valve drains
downstream, alleviating the excess pressure.
Pressure Reducing/Sustaining Valve
Applications
Use the pressure reducing/sustaining valve to
define two pressure zones along a supply line.
Typically, this occurs along a downhill flow.
Description
Pressure Reducing/Sustaining valves are piloted
hydraulic valves activated by line pressure and
controlled by pilots. Both pilots have spring-loaded
diaphragms. One pilot is responsive to upstream
pressure and the other to downstream pressure.
The combined operation of the two pilot valves
sustains the preset minimum upstream pressure
of the valve, and at the same time, reduces the
downstream pressure to a preset maximum
pressure. The valve opens or closes gradually to
maintain both required pressures simultaneously.
Available Models
• 3-way plastic piloted Pressure Reducing/
Sustaining valve. Plastic pilot is used for 2”-8”
sizes with pressure rating up to 145 PSI (10 bar).
• 2 and 3-way pressure Reducing/Sustaining valve
with pressure rating up to 232 PSI (16 bars).
Adjustment
• Adjust the pressure set points with the adjusting
screws on the pilots.
Function
The Pressure Reducing/Sustaining valve is
activated by the line pressure and controlled by
two pilot valves. Both pilots include spring-loaded
diaphragms. The sustaining pilot is preset to
sustain the upstream pressure at a preset point.
The reducing pilot reduces the downstream
pressure and maintains it at a lower preset level.
Under normal flow conditions, the valve is partly
open to sustain the upstream pressure and reduce
the downstream pressure. It partly closes when the
downstream pressure rises above the lower set
point or when the line pressure drops below the
upper set point. It opens again when the upstream
pressure rises. In 3-way pilot configurations,
the control chamber of the valve drains out to
atmosphere, enabling the valve to fully open.
In 2-way pilot configurations the control chamber
drains downstream, enabling faster reaction time
and gradual opening without water discharge.
Control Mode –
3-way Plastic/Metal Pilot
Control Mode –
2-way Pilot
Manual: Use the three-way selector to close
or open the valve by turning the handle to C
(closed) or O (open) positions.
Automatic: Position the three-way selector
handle to A (automatic). When the upstream
pressure is low, the line pressure flows
through ports 2-3 of the sustaining pilot
and flows into the valve’s control chamber.
The valve closes to sustain upstream pressure.
When the upstream pressure reaches the set
point, the diaphragm of the reducing pilot
moves upward and connects ports 2-3. The
control chamber drains through the sustaining
pilot and exits port 2 of the reducing
pilot. The valve then opens to the preset
downstream pressure. When the downstream
pressure is greater then the desired level, the
reducing pilot’s diaphragm moves up, allowing
water to flow into the control chamber
through ports 4-3 of the sustaining pilot.
Manual: To open the valve, open isolation
valves 1 and 2. To close the valve close the
downstream isolation valve. The upstream
isolation valve should remain open.
Automatic: When the upstream pressure
is low, the control chamber is connected
through the 2-way sustaining pilot to the line
pressure and the valve closes. When the line
pressure rises and overcomes the spring of the
sustaining pilot, the pilot’s diaphragm moves
upward to open port 5 (outlet downstream).
The control chamber then drains downstream
through the 2-way reducing pilot. The
valve then opens and reduces the upstream
pressure. As the line pressure is reduced, the
sustaining pilot closes, as does the valve. If the
downstream pressure is greater than the set
point of the reducing pilot, the reducing pilot’s
diaphragm moves upward and closes port 1
or 2 (outlet downstream). The control chamber
is connected to the upstream pressure and the
valve closes.
9
Quick Pressure Relief Valve
Applications
A Quick Pressure Relief Valve (QPR) protects
water systems from rapidly increasing excess
pressure. It is recommended to install the
Ooval QPR valve at the start of the system
near the main supply line or booster pump.
Description
The Pressure Relief Valve is a piloted hydraulic
valve activated by line pressure. The 2-way pilot
has a spring-loaded diaphragm that is sensitive
to upstream pressure. The valve is normally
closed. As the line pressure rises above the
preset level, the valve opens quickly to relieve
the excess pressure.
Available Models
The valve is a general application 2-way piloted
Pressure Relief Valve with a pressure rating up to
232 PSI (16 bar).
Function
The Pressure Relief Valve is activated by line
pressure. The displacement of the diaphragm in
the pilot is due to a rise in line pressure against
the spring force. As the pressure increases above
the set point, the water flow inside the pilot is
directed so that the valve quickly opens.
Control Mode
Automatic: When the line pressure is low, the quick relief pilot and the
valve are closed by line pressure. The valve remains closed until the line
pressure is higher than the set point of the pilot. As pressure increases
above the set point, the diaphragm moves upward under the line
pressure and port 5 (outlet downstream) of the pilot opens, allowing
the control chamber to drain through the vent. The Ooval valve opens in
a few seconds relieving the excess pressure.
10
Hydraulic/Electric Control Valve
Applications
On/Off electric valves are used for remote
control of hydraulic valves. Normally open
or normally closed configurations are
available.
Description
The valve opens or closes by electric command
through a selection of either 2-way or 3-way
solenoid valves. The solenoid opens or closes
the valve when energized by an electric signal.
The electric signal originates with a controller,
timer, sensor or remote control device.
Available Models
Three-way normally closed and 3-way normally
open electric control valve.
Two-way normally closed and 2-way normally
open electric control valve.
Function
2-way configuration: The valves control
chamber drains downstream, enabling faster
and gradual opening without water discharge.
3-way configuration: The valve control
chamber drains to atmosphere, allowing the
valve to open fully.
Control Mode
Normally Closed Mode: The line pressure is
connected to the Ooval valve’s control chamber
above its diaphragm via port P (pressure)
and port C (common). The diaphragm is
pressed downward against the valve seat
closing the valve. As an electric signal
energizes the normally open (NO) solenoid,
its plunger changes position and the control
chamber drains out through port V (vent).
The diaphragm is forced upward by the line
pressure and the valve fully opens.
Normally Open Mode: The valve’s control
chamber is connected to port C (common) of
the solenoid. The valve’s diaphragm is pressed
upward by line pressure keeping the valve in
the open position. As the normally closed (NC)
solenoid is energized by an electric signal, its
plunger changes position and the vent closes.
The control chamber of the valve becomes
connected to the pressure source via port P
(pressure) and port C and the valve closes.
N.O. Solenoid
C = Common
P = Pressure
V = Vent
N.C. Solenoid
11
Hydraulic Remote Control Valve
Applications
Use this valve with a hydraulic remote
control in those situations where the
command pressure is lower or higher then
the working pressure, or in situations where
there are topographic differences between
the command source and the line water
pressure at the valve. The hydraulic remote
control is also used where the use of wires
is not feasible.
Description
On/Off hydraulic remote control valves are used
for the remote control of hydraulic valves. In
normally closed (NC) configurations, the valve
remains closed until the hydraulic relay receives
a hydraulic command. In the normally open
(NO) model, the valve is open until the hydraulic
relay receives a hydraulic command to close.
Available Models
Normally open and normally closed
configurations are available. Operating pressure
is up to 145 PSI (10 bar). A pressure regulating
or pressure sustaining pilot may be used in
conjunction with the hydraulic relay.
Function
The valve is activated by line pressure and
controlled by the hydraulic relay. The relay
includes a spring-loaded diaphragm that
determines the pressure required to activate
the command. In the normally closed operation
(NC), the line pressure is connected to the
valve’s control chamber keeping the valve
closed. In the reverse case (NO), the valve
remains in the open position.
Control Mode
Normally Closed Mode: In normally closed
applications, when the command is received
by way of port 1, the line pressure port 2 is
prevented from entering the control chamber
through the connection between port 2-4 and
the water in the control chamber drains through
port 3, causing the valve to open.
Normally Open Mode: In normally open
applications, port 3 connects to the upstream
line pressure and water is prevented from
entering the bonnet chamber. When the
command is received by way of port 1, port 3
connects to port 4 and the valve closes.
12
Basic Valve
The basic valve can be operated
manually through the use of a 3way selector. Selector options are:
Closed: Upstream pressure or
pressure from an external source is
applied to the control chamber. The
diaphragm is pressed down to close
the valve drip-tight.
Open: Discharging the water or air
pressure to the atmosphere from
the control chamber causing the
valve to open.
Automatic: The automatic port
of the 3-way selector is connected
to a solenoid, hydraulic relay or
pilot which controls the valve. The
common port of the 3-way selector
connects the control chamber to
either A (automatic), O (open) or C
(closed), depending on the direction
the selector is pointed.
3 Way Plastic Relay
Standard Valves
Pressure Reducing
Maintains a constant downstream pressure regardless of upstream pressure
or flow rate fluctuations. The set point of reduced pressure is adjustable by a
2-way or 3-way pilot valve. A spring-loaded diaphragm inside the pilot moves
according to the downstream pressure changes. The pressure fluctuations are
compensated by gradual opening and closing of the valve.
Pressure Sustaining/Relief
Maintains the minimum preset upstream pressure regardless of changes of
pressure in the downstream or flow rate. Pressure relief is a sustaining valve
that releases excess flow from the system.
Quick Reacting Pressure Relief
A safety valve that opens instantly, but closes slowly to protect the system
against excessive pressure.
Manual
Opens and closes manually by means of a 3-way selector.
Electric
Valve opens or closes in response to an electric command using a
3-way solenoid.
Hydraulic Relay with Shastomit or Galit
A relay installed on the valve in the field is activated by a solenoid at the
control station.
Pressure Reducing/Sustaining
The combined operation of the two pilots sustains a constant pressure
upstream of the valve, and at the same time, reduces the downstream to
a preset pressure. Both pilots have spring-loaded diaphragms. One pilot
is sensitive to upstream pressure and the other to downstream pressure.
The valve opens or closes gradually to maintain both required pressures
simultaneously.
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Specialty Valves
Altitude Control Valve
Used to maintain a preset water level in a reservoir or water tank. The
valve is activated by line pressure according to the hydrostatic pressure.
The valve stays open as long as the water level of the reservoir is below a
preset level. As the water level rises, the valve gradually closes.
Electric Float Control Valve
The valve is a normally closed electric float control valve. A float hanging
over the water surface at the desired height switches the electric circuit.
When the water level drops below the float, the electric circuit is switched
on and opens the valve through a solenoid valve. As the rising water
reaches the float level, the circuit is disconnected and the valve closes.
Flow Rate Control Valve
The flow rate through the valve is determined indirectly using an orifice
plate. Normally the valve is partially open to allow a preset constant flow
rate. The pressure loss across the orifice is proportional to the actual flow
rate. Upon increasing pressure loss, the valve is automatically piloted
to close. When the pressure drops, the valve opens and the flow rate is
maintained in spite of the line pressure fluctuations or the downstream
demand.
Float Level Control Valve
Used to maintain a preset water level in a reservoir or water tank. The line
pressure activates the valve. The valve stays open as long as the water
level in the reservoir is below a preset level. As the water level rises and
floats the pilot’s arm, the valve gradually closes.
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Water Works & Irrigation Solutions
15
P.O. Box 880
Kiriat Malachi 83108 Israel
Tel: +972 8 8601005
Fax: +972 8 8601006
E-mail [email protected]
www.ooval.com
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