Bermad - Model 900 - Engineering Data

The BERMAD Model IR-900-M is a unique product integrating both a vertical turbine Woltman-type water meter and a diaphragm-actuated hydraulic control valve. The vertical turbine impeller drive is magnetically coupled to a vacuum-sealed meter register in the control head. Both the magnetic drive control head and its register(s) are hermetically sealed and are not affected by dirty water or environmental humidity.

The highly sensitive magnetic drive provides superior accuracy that exceeds all water meter standards. The available Reed Switch and Opto-Electric 4-20 mA transmitter options provide greater flexibility in electrical pulse generation. Serving as a Flow Meter and Main Valve, the BERMAD Model IR-900-M controls irrigation together with the irrigation controller.

The IR-900-M provides the full spectrum of metering functions – from simple visual readout, to pulse output for computerized data capture and control – while simultaneously allowing for numerous control valve features such as pressure, level, and flow control. Ranging in size from 11/2"; DN40 through 10"; DN250, the 900-M Series is specifically designed for metering and control applications in agricultural and landscape irrigation as well as in municipal & industrial water supply systems. The flow metering unit is vertical to the pipeline and includes an impeller with integrated inlet and outlet flow straighteners. This internal design eliminates the need for straightening distances, enables vertical or horizontal installation, and ensures accuracy even when the valve is partially open during pressure or flow control tasks. The impeller assembly shaft serves as the closure assembly guide, while also centralizing and tightening all internal parts both in their position and to one another.

The basic Model IR-900-M combines simple and reliable construction with superior performance, while at the same time being virtually free of the typical limitations associated with other single chambered valves. The relatively high impeller housing raises the location of the vulcanized seal seat above the valve body. This results in remarkable cavitation resistance and a smooth mushroom-shaped flow where the valve body is distanced from the flow. The closure assembly, combining a rugged radial disk harnessed to a flexible fiber-reinforced diaphragm, slides on the guide along the full valve travel. The diaphragm is carefully balanced and peripherally supported to avoid distortion, resulting in long-life and controlled actuation even under harsh conditions. One diaphragm and spring fully meet the valve's operating pressure range requirements. The cover is removable via fastening bolts for quick in-line inspection and service. All the internal assemblies can be easily removed from the valve body with no need for disassembling the valve from the line.

Features & Benefits

• Integrated “All-in-One” Control Valve
  • Saves space, cost and maintenance
• Hydraulically Controlled Hydrometer
  • Line pressure driven
• Magnetic Drive Register:
  • Analog rotating hands display
    • Water-free gear train mechanism
    • Various pulse combinations
• Internal Inlet & Outlet Flow Straighteners
  • Saves on straightening distances of pipe
  • Maintains accuracy
• Integrated Flow Metering Calibration Device
  • Precise measurement
• User-Friendly Design
  • Simple in-line inspection and service

Typical Applications

• Computerized Irrigation Systems
  • Irrigation Control Head
  • In-Field Control Head
• Remote Flow Data Read-Out
  • Flow Monitoring & Leakage Control
  • Water Treatment Systems
  • Volumetric Irrigation Systems

Exploded View

[1] Control Head

Includes: Vacuum-sealed meter register, magnetically coupled to the impeller drive. Hermetically sealed control head and its register(s). High sensitivity, providing superior accuracy that exceeds all water meter standards. Range of Reed Switch and Opto-Electric 4-20 mA transmitter options provide greater flexibility in electrical pulse generation.

[2] Valve Cover

Locates, centralizes, and fastens diaphragm, spring, and impeller assembly ensuring smooth and accurate performance. Simple and light construction enables quick in-line inspection and service.

[3] Auxiliary Closing Spring

One single spring fully meets valve requirements for operating pressure range, ensuring low opening pressure and secured closing.

[4] Closure Assembly

Combining a rugged radial disk harnessed to a flexible fiber-reinforced diaphragm. The fully guided closure assembly and the carefully balanced and peripherally supported diaphragm prevent distortion and protect the elastomer, resulting in long-life and controlled actuation even under harsh conditions. One diaphragm and spring fully meet the valve's operating pressure range requirements.

[5] Impeller Assembly

[5.1] Guide – Carries the transmission shaft, guides the closure assembly, and centralizes and tightens all internal parts.

[5.2] Upper Flow Straightener – Tightens the seal seat in place, straightens outlet flow and creates a mushroom-shaped flow.

[5.3] Impeller – Woltman-type impeller with tungsten carbide shaft tips and bearings for high, long-term accuracy and negligible wear.

[6] Impeller Housing

[6.1] Lower Flow Straightener – Straightens inlet flow, eliminating the need for straight upstream pipe required in standard water meters.

[6.2] Seal Seat – Metal ring vulcanized with an elastomeric seal, raised and remote from the valve body to prevent cavitation damage.

[7] Integrated Calibration Device

Enables recalibration instead of renovation when the recommended standard accuracy period has elapsed (The Calibration Device is stamped closed with a metal seal).

[8] Wide Body

Hydro-dynamically designed for efficient flow with minimal pressure loss and excellent resistance to cavitation.

[8.1] End Connections conform to pressure ratings and standards: ISO, ANSI, JIS, BS, and others.

On-Off Modes, Local Manual Control

On-Off Modes, Solenoid Controlled

2-Way Modulating Modes, Pressure Reducing Pilot

3-Way Control Modes, Pressure Reducing

2/3-Way Modulating Modes, Flow Control

Construction materials

Available Patterns, Sizes & End Connections:

Connections Standard:

Flanged: ISO 7005-2 (PN10 & 16)

Triangle Flange (DN65 inlet only)

Threaded: Rp ISO 7/1 (BSP.P) or NPT

Pressure Rating: PN16

Operating Pressure Ranges:

PN10: 0.5-10 bar

PN16: 0.5-16 bar

For Lower Pressure requirements, consult Deeco.

Temperature: Water up to 50°C

Pulse Options:

Pulse Electric Data:

Reed-Switch:

Switching voltage: 48 VAC/DC max

Switching current: 0.2A max

Switching power: 4W max

Opto-Electric:

Supply voltage: 5-12 VDC

Output type: complimentary

Output current: 200 mA

Dimensions and Weights

Flow Charts

Flow Properties

Valve flow coefficient, Kv or Cv Kv(Cv)=Q√Gr/ ∆P

Where:

Kv = Valve flow coefficient (flow in m3/h at 1bar Diff. Press.)

Cv = Valve flow coefficient (flow in gpm at Diff. Press. 1psi)

Q = Flow rate (m3/h ; gpm)

∆P = Differential pressure (bar ; psi)

Gf = Liquid specific gravity (Water = 1.0)

Kv = 0.865 Cv

Flow resistance or Head loss coefficient, K=∆H(2g/v²)

Where:

K = Flow resistance or Head loss coefficient (dimensionless)

∆H = Head loss (m ; feet)

V = Nominal size flow velocity (m/sec ; feet/sec.)

g = Acceleration of gravity (9.81 m/sec2 ; 32.18 feet/sec2)

Equivalent Pipe Length, Leq, Leq = Lk·D

Where:

Leq= Equivalent nominal pipe length (m; feet)

Lk = Equivalent length coefficient for turbulent flow in clean

commercial steel pipe (SCH 40)

D = Nominal pipe diameter (m; feet)

Note:

The Leq values given are for general consideration only.

Accuracy Table