Power Reactor Embrittlement Program

Several industry databases of surveillance test data have been maintained over the years. For example, during the 1990s EPRI maintained the Power Reactor Embrittlement Program (PREP) database (EPRI, 1996), which was developed under joint EPRI and CRIEPI (Central Research Institute of the Electric Power Industry) sponsorship. Later, EPRI sponsored the RPVDATA database program (EPRI, 2000) as a successor to PREP. The industry databases have faced greater sustainability issues than the NRC databases because of limited funding. 

EPRI (1996), PREP4 Power Reactor Embrittlement Program, Version 1.0, SW-106276, Electric Power Research Institute, Palo Alto, CA. 

The latest version, PR-EDB Version 3, contains test results of 104 HAZ materials, 115 weld materials and 141 base materials, including 103 plates, 35 forgings and three correlation monitor materials that were irradiated in 321 capsules from 106 commercial power reactors. It was a Windows PC-based program (Windows 98 through XP only) using data files in MS Access format. It is being replaced by the Radiation Embrittlement Archive Project (REAP) (Klasky et al., 2013). 

In this chapter, after giving an overview of the embrittlement of Western pressurized water reactor (PWR) reactor pressure vessel (RPV) beltline materials, together with the characteristics of PWR RPVs, such as their general specification, core region materials and the effects of variables on embrittlement, the surveillance database obtained from US, French and Japanese nuclear power plants (NPPs) and those from other countries is presented based on open literature. The surveillance program of each country is also briefiy described. Trends of surveillance data which will be obtained in the near future are described. The possibility of new data from reconstituted and miniature specimen techniques is described. 

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