Construction of a pressurized thermal shock testing system to evaluate the structural integrity assessment of a PWR nuclear power plant pressure vessel

In a Pressurized Water Reactor (PWR) nuclear power plant, the reactor pressure vessel (RPV) works as the contention of the nuclear reactor core and of the refrigerant of the primary cooling system. To extend the useful life of these plants, the residual life of their components must be assessed along its time of operation. The pressurized thermal shock (PTS) is an important event to be considered in relation to the reactor pressure vessel integrity. The scientific community has been invested time and money conducting several tests in order to have a better understanding of the effects of such event (PTS). The pressurized thermal shock test consists in the construction of a scaled simplified RPV model containing a determined number of cracks with controlled geometry and positions. The model is then submitted to predetermined conditions of temperature and pressure, inducting a thermal shock using a cold water flux on its external surface. Several studies related to the mentioned PTS event and mounting of a test assembly that allows the simulation of loading conditions caused by a pressurized thermal shock were conducted by the Nuclear Technology Development Center (CDTN) in order to this test. Construction of a pressurized thermal shock system is presented in this paper. (author)