Bypass is designed for filling the downstream section of a penstock with water and equalizing pressure on both sides of the disk (rotor) before opening the valve. The bypass inlet flange is attached to the inlet pipe of a butterfly (spherical) valve, and the bypass outlet flange is connected to the expansion joint housing.
Hydraulic valve (valve with hydraulic drive) is the bypass shutting-off device driven by oil pressure from OPU.
Bypass is equipped with a safety shutter to allow for repair of the hydraulic valve without dewatering the penstock.
