A METHOD AND A DEVICE FOR EVALUATING THE INTEGRITY OF A CONTROL SUBSTANCE IN A NUCLEAR PLANT

摘要

The invention refers to a method and a device for evaluating the integrity of a control rod material in a nuclear plant. The plant includes a reactor vessel (1), a reactor core (2) that is enclosed in the reactor vessel and formed by a number of nuclear fuel elements (3) and a number of cladding members (4), in which said control material is enclosed, and a circuit (6) that permits a flowing of a fluid through the reactor core and through an external conduit arrangement. In order to estimate the integrity of the control material, the value of at least one primary parameter that includes the concentration of a substance, which is released from the control rod material during the operation of the nuclear plant, is determined (21, 23, 28) in said fluid. Furthermore, the value of at least one operational parameter related to said fluid is determined (30, 33, 34, 36). The value of said primary parameter is standardised with respect to the value of said operational parameter, and the standardised value of said primary parameter is analysed of said estimation of the integrity of the control rod material.