The Model BV60 Brodie Control Valves are back pressure regulators designed to maintain a specific minimum upstream pressure regardless of fluctuations in flow rate or downstream pressure. When correctly installed and adjusted, the Model BV60 valve will maintain up-stream pressure at a value within 5 PSI (34.48 kPa) of the valve pilots setting. A minimum pressure differential across the valve of 15 PSI (103 kPa ) is required for it to fully open.
Principle of Operation
The Model BV60 valve is controlled by a back pressure pilot which senses line pressure at a selected point upstream of the valve and throttles the valve to maintain a desired minimum pressure at that point. If line pressure at the sense point exceeds the setting of the pilot, the pilot throttles the valve open until the correct pressure level is reached. Conversely, if line pressure at the sense point falls below the setting of the pilot, the pilot throttles the valve closed until the correct pressure level is reached. In the static condition, both the pilot and valve are closed. When the pump is activated, the initial pressure developed at the valve intake is applied to the top of the valve piston, keeping it tightly seated and preventing all flow. As pump discharge pressure rises, it soon exceeds the set point of the pilot, which then opens the valve to provide flow.
Once the valve has opened and continuous flow is established, the pilot monitors upstream pressure and compares it with the set point. If upstream pressure is greater than the set point, the pilot vents the pressure on top of the valve piston downstream, and the valve opens wider to conduct more flow. If upstream pressure is less than the set point, however, the pilot applies additional pressure to the top of the valve piston, and the valve throttles closed to restrict flow. The valve will limit flow in this manner in order to maintain the required minimum back pressure. A needle valve is included as a sensitivity adjustment used to regulate the speed at which the valve opens and closes.
Design Features
Modular construction -all internal parts including seat ring can be removed with the cylinder assembly without disturbing line connections.
No diaphragms or stuffing boxes
45° body design assures high capacity
Positive shut-off
Uniform speed of response
Linear control characteristics
Inherently checks reverse flow
O-Ring plus metal-metal seat
Tapered ports for better low flow response
Valve Capacity Data:
Valve Size 3": 186 Cv-gpm*
Valve Size 4": 309 Cv-gpm*
Valve Size 6": 688 Cv-gpm*
*Cv based on wide open valve utilizing water at 60F (15.6C)
Materials of Construction
Main Valve Body: Steel-ASTM-A216-GR-WCB
Main Valve Cylinder: 17-4 Stainless Steel, Heat Treated
Main Valve Piston: Stainless Steel
Seat Ring: Stainless Steel
O-Rings: Viton Standard (Other elastomers available)
Other Internal Parts: Stainless Steel
Pilot Valve Strainer/Needle Valve Strainer: Standard: Steel
Tubings and Fittings: Standard: Steel
Optional Equipment
Independent Opening Speed Control
Stainless Steel Tubing
Thermal Relief
Additional Pilot COntrol Functions
Excess Flow Shutoff (Pressure Sensitive)
Pilot Line Isolation Block Valves
Manual Override (Opens Valve)
Epoxy coating main valve body unmachined surfaces
Availabe Flange Connections
3"-6" 150 lb. ANSI, Max Working Pressure @100°F: 285 PSI
DN 80-DN150 PN 25, Max Working Pressure: 25 Bar
3"-6" 300 lb. ANSI, Max Working Pressure @100°F: 740 PSI
DN 80-DN150 PN 64, Max Working Pressure: 51 Bar
