CCI Switzerland has received from Doosan an order for two turbine ventilator valves for the two supercritical 800 MW turbines of the coal-fired Yong Hung power plant in Korea. These turbines are among the largest turbines for supercritical steam conditions. The valves are 7-in. x 10- in (180-mm x 250-mm) with a 5-in. (130-mm) seat. The purpose of the valves is to protect the high-pressure turbine from overheating during start-up and turbine load rejection. The valves are therefore hydraulically operated and have a spring to open the valve safely within one second against the steam pressure, whenever the turbine protection system is sending the trip signal. The valves have a design pressure of 3436 psig (238 bar) and a design temperature of 1047 F (564 C).
This is the first time that CCI is supplying this type of valve for a General Electric license turbine. To win this order CCI proposed a new design for the valve which was simpler and more cost-effective than the previously used design.
