Abstract. The pressure tubes from the PHW reactors contain inside the nuclear fuel bundles. Through the remained free space the heavy water runs, used as moderator. The pressure tubes are introduced coaxially inside the calandria tubes by means of garter springs. Within the pressure tube/calandria tubes space heavy water flows as cooling agent. The eddy current nondestructive control during the in-service inspection implies the evaluation of the garter springs position, of the pressure tube/calandria tube separation, as well as of the local modifications of electric conductivity of the material (2.5%Nb-Zr alloy) the pressure tubes are made of, produced by the hydrogen absorption and resulting in the occurrence of Zr hidrides which can lead to blistering. This work presents a new type of eddy current transducer destined to the inspection of pressure tubes, a transducer of send-receive absolute type making use of the rotating magnetic field method [1].

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