Japan's Mitsubishi Heavy Industries (MHI) and France's Comex Nucléaire, a subsidiary of ONET Technologies, have been awarded a contract by Electricité de France (EdF) to supply six replacement steam generators (RSGs).
|A replacement steam generator (Image: MHI)
In pressurized water reactors (PWRs), steam generators transfer the thermal energy generated in the reactor vessel to a secondary coolant and feeds the resulting steam to a turbine system to generate electricity. The replacement steam generators are 21 metres in height and weigh some 300 tonnes each. Their pressure-resistant containers - made of low-alloy steel (containing manganese, molybdenum and nickel) - each house more than 4000 heat transfer tubes manufactured of a thermally treated nickel-chromium-iron alloy.
The replacement steam generators will be manufactured at MHI's Kobe shipyard. Delivery of the RSGs will begin in 2013 and will be completed in 2014. Under the contract, Comex Nucléaire will provide the engineering and specific studies; reconciliation with French standards and regulations; licensing support; supervision of subcontractors; the inland transport of the RSGs; and, on-site supervision of the installation of the components.
EdF is in the process of replacing all the steam generators at its PWR plants which began operating in the 1980s. It has not been disclosed which EdF reactors the RSGs are destined for.
MHI received its first order from EdF for the supply of replacement steam generators in 2005. The latest order brings the total number of replacement steam generators supplied by MHI to EdF to twelve. Altogether, MHI has received overseas orders for 22 RSGs, including from Belgium and the USA.
Comex Nucléaire has been cooperating with MHI since 2002.