1. The Blowdown valve function is to vent the turbine shaft packing between the high pressure and reheat turbine sections to condenser as a result of turbine trip or loads loss, and then to prevent the turbine to overspeed caused by the steam in the HP turbine section to flow along the turbine shaft into the reheat section through the shaft packing.
2. The valve can be opened quickly in small thrust because of pilot type seat.
3. Advantages in maintenance, hard packing structure, no need gland packing.
4. Reinforced sealing system between body and bonnet by hot bolting connection.
5. Operated by pneumatic actuator.