The Brodie International Model BV86 Two-Stage Control Valve is a two-stage hydraulically actuated control valve designed to utilize the flow stream as the source of power. It is commonly used with a positive displacement flowmeter with a mechanical preset counter to provide shock-free two-stage closure. Through the use of optional accessory pilots, mounted in series with the BV86 pilot, functions such as back pressure, pressure reducing, or rate of flow control can be obtained.
Principle of Operation
The valve is pilot operated on a balanced piston principle, spring biased to a closed position. Pressure differential overcomes the force of the spring, causing the main valve to open and establish flow. The pilot control(s) vary the pressure on the spring side of the piston for a position. The Hydraulic pilot is mechanically attached to and actuated by the preset counter of the flowmeter, and is hydraulically connected to the shut-off valve.