OREANDA-NEWS. August 26, 2014. The VVER-1000 reactor vessel for the third unit of the Tianwan nuclear power plant in China's Jiangsu province has successfully completed hydraulic tests at the manufacturing plant in Russia.

Made by OMZ subsidiary Izhorskiye Zavody, the pressure vessel was placed on a test stand and subjected to internal pressure of 24.5 MPa to prove the durability of the metal as well as its welded joints.

The tests were supervised by a commission which included representatives from OKB Gidropress, VO Safety, Atomproekt, Izhorskiye Zavody, as well as from the customer, Jiangsu Nuclear Power Corporation (JNPC). JNPC is a joint venture between China National Nuclear Corporation (50%), China Power Investment Corporation (30%) and Jiangsu Guoxin Group (20%).

Having successfully completed the pressure test, the next step for OMZ is the trial assembly of the reactor internals and the vessel head. The company said that this is "one of the final stages in the manufacturing process of the reactor vessel prior to shipment to the customer."

Izhorskiye Zavody was awarded a contract in 2010 for the manufacture of the reactor vessels for Tianwan units 3 and 4. The company previously supplied the vessels used in the first two units there.

Construction is currently under way on Tianwan 3 and 4 - known as Tianwan Phase II - with the two Russian-designed VVER-1000 pressurized water reactors scheduled to enter service in 2017 and 2018. They will join the two VVER-1000s making up Phase I of the power plant, which have been in operation since 2007.