The Model 790-M Burst Control Valve is a hydraulically operated, diaphragm actuated control valve that upon sensing flow in excess of setting shuts off and locks drip tight until it is manually reset. As long as the flow is lower than the setting, the valve remains fully open, minimizing head loss.
The Model 790-M is a pilot controlled valve equipped with an adjustable, 2-Way, high sensitivity, differential pressure sustaining pilot.
The pilot , senses valve differential pressure.
Should that pressure rise above pilot setting, the pilot opens, introducing upstream pressure into the upper control chamber , causing the main valve to begin an irreversible “close & lock” process. Opening and resetting the main valve requires manual intervention by means of the manual reset valve . When differential pressure is below pilot setting, the pilot blocks upstream pressure from the control chamber, and the main valve remains fully open.
The manual test valve  enables simulation of burst conditions and valve response. After testing, reset procedure is required. The mechanical flow stem  enables adjusting the closing point, to meet various flow regimes.
Body & Cover: Brass or Stainless Steel
Elastomers: Synthetic Rubber
Spring: Stainless Steel
Internal parts: Stainless Steel
Diaphragm Covers: Fusion bonded epoxy coated Steel or Stainless Steel
Tubing & Fittings: Stainless Steel 316 or Copper & Brass
Accessories: Stainless Steel 316, Brass and Synthetic Rubber Elastomers
Every water system is vulnerable to bursts, whether due to system problems or external mechanical damage. This illustration shows a reservoir feeding a downhill line with lower elevation consumers. In case of burst, each Model 790-M protects against flooding lower elevation consumers.
The Model 790-M, installed at the reservoir outlet, also protects against reservoir emptying.
Size Range: DN40-900 ; 11/2–36”
Flanged: ISO PN16, PN25 (ANSI Class 150, 300)
Threaded: BSP or NPT
Others: Available on request
Valve Patterns: “Y” (globe) & angle, globe (DN600-900 ; 24”-36”)
Working Temperature: Water up to 80°C ; 180°F
Body & Actuator: Ductile Iron
Internals: Stainless Steel, Bronze & coated Steel
Diaphragm: Synthetic Rubber Nylon fabric-reinforced
Seals: Synthetic Rubber
Coating: Fusion Bonded Epoxy, RAL 5005 (Blue) approved for drinking water or Electrostatic Polyester Powder
Please specify the requested valve in the following sequence: (for more options please contact us)