BERMAD 700 SIGMA EN/ES series are hydraulically operated, oblique pattern control valves with high cavitation resistance, excellent flow capacity and double chamber unitized actuator, that can be disassembled from the body as a separate integral unit. The valves hydrodynamic body is designed for unobstructed flow path and provides an excellent and highly effective modulation capacity for high differential pressure applications, with minimal noise and vibrations. The 700 SIGMA EN/ES series meet all flange connection standards. 700 SIGMA EN – Full port valve with extraordinarily high flow capacity enabling optimized used of resources and minimizing energy costs. 700 SIGMA ES - Designed mainly for regulating applications achieving the best performance under variable flow velocities in pipes
BERMAD’s 700 SIGMA EN/ ES series has various plug options to enable different valve characteristics.
Flat plug - standard plug for on-off and high flow applications.
V-Port plug - uniquely designed throttling plug. It changes the ratio of flow to stem travel allowing very wide flow range with relatively high pressure reduction and provides more accurate, stable and smoother response during pressure and flow regulation, while reducing noise and vibration.
BERMAD’s 700 SIGMA EN/ ES series plugs can easily be change before or after valve installation on site.
The cavitation phenomenon has a significant affect on control valve and system performance.
When the fluid’s static pressure reaches liquid vapor pressure, vapor cavities (bubbles) form and grow until they violently implode by the recovered pressure downstream to the valve seat.
The implosion of these cavities generates high-pressure surges, micro jets and intensive heat, which erode valve components and downstream piping. In its final stage, cavitation flashes and chokes the flow.
The Cavitation Guide is based on the formula commonly used in the valve industry:
σ= (P2-Pv) / (P1-P2)
Where:
σ= Sigma, cavitation index, dimensionless
P1 = Upstream pressure, absolute
P2 = Downstream pressure, absolute
Pv = Liquid vapor pressure, absolute
(Water, 18°C = 0.02 bar-a ; 65°F = 0.3 psi-a)
Notes:
1. An alternate cavitation index formula introduced by
ISA is:
σISA = (P1-Pv) / (P1-P2) which equals σ+1
2. The below charts should be considered only as a general guide.
3. For optimum system and control valve application please contact us.
The BERMAD Single Cavitation Cage trim is designed to reduce cavitation, noise and vibration under higher differential pressure operation, as well as smart pressure reducing.
The BERMAD Double Cavitation Cage trim is designed to resist cavitation, cavitation damage, noise and vibration under extreme differential pressure operation, as well as smart pressure reducing.
Valve Patterns: “Y” (Globe)
Pressure Rating: 25 bar; 400 psi
End Connections: Flanged (all standards)
Plug Types: Flat disc, V-port , Cavitation cages
Temperature Rating: 60°C; 140°F for Cold water applications.
Optional higher temperature: Available on request
Body & actuator: Ductile Iron
Bolts, nuts & studs: Stainless Steel
Internals: Stainless Steel, Bronze & Coated Steel
Diaphragm: Fabric-reinforced synthetic rubber
Seals: Synthetic rubber
Coating: Dark blue Fusion bonded epoxy
For other materials please contact us.
* Charts represents fully open valves. Please contact us for proper valve sizing.
Valve Patterns: “Y” (Globe)
Pressure Rating: 25 bar; 400 psi
End Connections: Flanged (all standard)
Plug Types: Flat disc, V-port, Cavitation cages
Temperature Rating: 60°C; 140°F for Cold water applications.
Optional higher temperature: Available on request
Body & actuator: Ductile Iron
Bolts, nuts & studs: Stainless Steel
Internals: Stainless Steel, Tin Bronze & Coated Steel
Diaphragm: Fabric-reinforced synthetic rubber
Seals: Synthetic rubber
Coating: Dark blue Fusion bonded epoxy
For other materials please contact us.
The BERMAD Independent Lift Check feature is an integral, lift type, spring loaded non return trim that allow full control and regulation in the required direction and smoothly closes drip tight before flow changes direction, regardless of control status.
The BERMAD Back-up Safety feature is a Triple Chamber actuated valve, where the third control chamber enables a fail safe mechanism and is recommended in critical or sensitive water systems to ensure continuous operation of the system.
The BERMAD Insertion Flow Meter can be inserted into the upstream side of the 700-Sigma EN/ES valves, adding accurate flow measurement function.
The BERMAD Valve Position Indicator Assembly provides a visual indication of valve opening and regulation behavior.
The BERMAD Single Limit Switch Assembly includes mechanical electrical change over contacts (NO + NC), enabling remote signaling of the closed valve position.
The BERMAD Double Limit Switch Assembly includes two mechanical electrical switches, enabling remote signaling of the closed and the open valve positions.
The BERMAD Flow Stem Assembly enables limiting the opening stroke of the control valve or for safety ensured mechanical closure.
The BERMAD Lifting Spring Assembly enables the valve to remain open at zero pressure conditions and to minimize pressure losses.
The BERMAD Analog Valve Position Transmitter Assembly enables remote signaling of the valve’s relative position.