A method of monitoring the fuel can leak tightness at WWER-440 nuclear power plants

Till 1986, the leak tightness of the fuel element cladding at the V-1 and V-2 nuclear power plants in Jaslovske Bohunice was checked solely by using the Canister system. In order to upgrade this testing, the Bohunice NPP management purchased a Sipping-In-Core facility from Siemens-KWU. The first results of leak testing using this facility were obtained in 1986 at the V-1 nuclear power plant. Since then, the facility has been in use during all shutdowns at both power plants, V-1 and V-2. In efforts to make a more efficient use of the Sipping facility, a continuous mode of the fuel cladding leak testing is proposed; for this, the fuelling machine and the Sipping evaluating device have to be modified. The assets of the continuous monitoring are most marked during the rearrangement of all the fuel elements from the core cage, i.e. during the extended shutdown associated with an inspection of the internal parts of the reactor. (Z.S.). 1 tab., 3 figs., 17 refs