Control valves for pressurized water reactors
Westinghouse Electric Company has awarded Emerson Process Management more than $8 million in purchase orders for critical control valves to be used in two AP1000 pressurized water reactors at SCANA Corporation’s Virgil C. Summer Nuclear Generating Station in Jenkinsville, South Carolina. With site preparation already underway, construction is scheduled to begin late this year or early next year. The two new reactors are scheduled to begin commercial operation in 2016 and 2019, respectively.
Emerson was selected for this project based on its experience in producing valves for the same applications in other AP1000 plants. The Fisher control valves covered by the purchase orders are identical to those selected for the first four AP1000 nuclear power units being built in China and two additional units in the US Southeast.
Fisher air-operated control valves will serve as part of the safety-related system in the nuclear containment area. Engineered to comply with ASME Section III standards for components of nuclear facilities, they undergo rigorous qualification testing at the new Emerson Innovation Center in Marshalltown, Iowa. Valve actuators are sized in accordance with EPRI (Electric Power Research Institute) guidelines to ensure adequate operating margins that meet industry standards. They are also designed and tested to survive vibration loads of six times gravity in three axes to confirm they can operate after a seismic event.
For the passive residual heat removal system, Emerson developed a specially modified ball valve that meets all specified flow requirements and fits in the limited space available. These valves have received extensive testing to prove their ability to provide highly efficient flow through natural convection without assistance from the reactor coolant pump. Testing has also demonstrated tight valve shut-off when the plant is in operation to maintain efficiency and accurate throttling control for all flowing conditions.
Emerson Process Management