Radiographic Examination of Electric Heater Tube Weld for HPR1000 Pressurizer

HPR1000 (Hua-long Pressurized Reactor) nuclear power technology is a third generation nuclear power technology independently developed by China and has completely independent intellectual property rights. The pressurizer is one of the most important equipments in nuclear power plants. Compared to the regulator of the CPR1000 pressurizer, the HL-1000 pressurizer designed by CNPDC has as many as 108 electric heaters. Each electric heater contains a weld of electric heating sleeve to connection. RT should be completed at least 216 exposures, if each weld is exposure with a minimum of two 90 degree shots, in this paper, the authors have improved RT examination technique of these welds and verified it on the actual products. The results show that the new technique can reduce the number of exposures by more than one third and speed up the manufacture of the whole pressurizer regulator.