Flowserve Corporation, a provider of flow control products and services for global infrastructure markets, has shipped the first of several main steam isolation valves (MSIVs) to the Sanmen Nuclear Power Plant, located in the Zhejiang Province of China. The MSIVs will be installed in Unit 1 of the plant, the first Westinghouse AP1000 nuclear power plant ever built.
(Flowserve’s MSIV helps isolate the main steam line between the steam generator and the turbine. )
The massive MSIV utilizes a Flowserve Edward gas/hydraulic actuator. As part of the secondary system of the pressurized water reactor (PWR), the MSIV helps isolate the main steam line between the steam generator and the turbine. The total assembly of the valve and actuator together stands more than 6.1 m (20 ft.) tall and weighs more than 25,900 kg (57,000 lbs.). The MSIV is designed to close within 3 to 5 seconds, which can be critical in the event that the plant operations need to be shut down quickly.
The AP1000, the Westinghouse advanced passive pressurized water reactor, incorporates a new design that is said to require 50 percent fewer safety-related valves, 80 percent less safety-related piping and 85 percent less control cable. This design also utilizes gravity in lieu of mechanical equipment to provide emergency cooling water flow.