摘要:
The invention relates to an induction heating method implemented in a device for heating a metal part, the device including magnetically coupled inductors (Ind1, Ind2, ..., Indp), each inductor being powered by a dedicated inverter (O1, O2, ..., Op) combined with a capacitor (C1, C2, ..., Cp) such as to form an oscillating circuit (OC1, OC2, ..., OCp). The oscillating circuits have at least approximately the same resonance frequency, each inverter is controlled by a control unit (M1, M2, ..., Mp) such as to vary the amplitude and the phase of the current passing through the corresponding inductor, the device also including a means for determining said current as well as a means for determining an actual temperature profile (θ 1 mes , θ 2 mes , ..., θ n mes ) of said part. The method includes the following steps: a) comparing said actual temperature profile with a reference temperature profile (θ 1 ref , θ 2 ref , ..., θ n ref ) and calculating a profile of the reference power density (Dp ref 1 , Dp ref 2 , ..., Dp ref n ) which the heating device must inject into said part; b) calculating the target currents which the inverters must produce in order for the currents of the inductors to reach target values (I 1 ref , I 2 ref , ..., I P ref ) that are suitable for injecting said reference power density profile into said part; c) determining the currents passing through the inductors in order to compare said currents with said target values and determine current deviations (δI 1 corr , δl 2 corr , ..., δl p corr ) to be corrected, and sending correction instructions to said control units (M1, M2, ..., Mp) in accordance with said current deviations.
摘要:
The present invention relates to the treatment of a heater tube intended to be used in a pressurizer of the primary cooling system of a nuclear reactor. In particular, the heater tube comprises a heater (1) housed in a substantially cylindrical sheath (5). The material of which this sheath is made may be a work-hardened austenitic stainless steel. In particular, the external surface of the sheath (5) is liable to undergo a stress corrosion during use of the heatertube. In the context of the invention, the method includes a heat treatment step, preferably using induction heating, in which the external surface of the sheath is heat-treated so as to recrystallize the material of the sheath at least on the surface thereof.