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700 ES

700 ES
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BERMAD Waterworks 700-ES Series On-Off Modes Closed Position Open Position Powered Open Position Line pressure applied to the upper control chamber of the valve creates a superior force that moves the valve to the closed position and provides drip-tight sealing. Discharging the pressure in the upper control chamber to atmosphere or some other lower pressure zone causes the line pressure acting on the seal-disk to move the valve to the open position. Line pressure is applied to the lower control chamber as pressure in the upper control chamber is vented. This, together with the line pressure acting on the seal-disk, creates a force that powers the valve to the open position. Closed Position Modulating Position Open Position The closed adjustable pilot valve traps line pressure in the upper control chamber. The resulting superior force moves the valve to the fully closed position and provides drip-tight sealing. The pilot valve senses line pressure changes and opens or closes accordingly. It controls the accumulated pressure in the valve upper control chamber, causing main valve to modulate to an intermediate position and maintain the preset pressure value. The open pilot valve releases line pressure from the upper control chamber. The line pressure acting on both the lower control chamber and the seal-disk, moves the valve to the open position. Modulating Mode Pressure Reducing * All text written above is valid for both 700 and 800 Series.

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BERMAD Waterworks 700-ES Series Technical Specifications 700 ES Series Available Sizes & Patterns ■ DN 40 - DN 600 (1½” - 24”) - Y Pattern Pressure Rating ■ PN 25 (according to connection rating) Connection Standard ■ Flanged: ISO 7005-2 (ISO 10, 16 & 25) Water Temperature ■ Up to 80ºC Standard Materials ❏ Main valve body and cover Ductile iron to EN 1563 or ASTM A-536 ❏ Main valve internals Stainless steel, bronze & epoxy coated steel ❏ Control Trim Stainless steel, Brass, bronze accessories Stainless steel 316 fittings & tubing ❏ Elastomers Synthetic Rubber ❏ Coating Blue fusion bonded...

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B€RMAD Waterworks Flow Data Angle V-Port Valve flow coefficient, Kv or Cv

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B€RMAD Waterworks Cavitation Cavitation The cavitation phenomenon has a significant affect on control valve and system performance. Cavitation may damage the valve and piping by the affects of erosion and vibration. Cavitation also generates noise and may limit and ultimately choke the flow. As the pressure differential across the valve increases, the static pressure of the flow passing through the throttling area of the valve (Vena Contracta) drops sharply. When the fluid’s static pressure reaches liquid vapor pressure, vapor cavities (bubbles) form and grow until they violently implode by...

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