| 摘要 |
The invention relates to methods of vortex-current control of tubes and can be used, for instance, for defectoscopy of tubes of heat exchangers in nuclear and heat engineering, chemical industry, municipal economy, etc. A rotary vortex-current probe for defectoscopy of inner surface of tubes consists of body, motor, rotor, attachable eddy-current converter, circuit for signal exchange between the rotary and fixed sections of the probe, mechanism for probe centering with respect to inner surface of tubes and cable for connection of the attachable eddy-current converter to control system. The circuit for signal exchange between the rotary and fixed sections of the probe consists of fixed and rotary components, those are placed on the body and the rotor, respectively. The motor and the centering mechanism are connected to the body. Axle of the motor is connected to the rotor, axis of rotation of that one coincides with the axis of the controlled tube. The rotor is installed on the bearing, its ring is fixed on the body. The attachable eddy-current converter is installed on the rotor and is provided with elastic mechanism for pressing it to inner surface of controlled tube with given gap. To the probe introduced are an additional centering mechanism and second bearing, inner ring of that one is fixed to the opposite from the motor end of the rotor, and the outer ring is connected to additional centering mechanism. Circuit for signal exchange between the rotary and fixed sections of the probe is arranged as a rotary transformer with windings placed in concentric slots at the end surface of toroidal magneto-dielectric cores with rectangular cross sections. Windings in the fixed and rotary cores of the rotary transformer are made with same diameters. The fixed core is connected to the main body, and the rotary core is connected to the rotor. The fixed and the rotary cores are placed coaxially with minimal gap in such a way that the slots with windings of the rotary transformer adjoin each other. The technical result is in that the probe proposed makes it possible to increase sensitivity of control due to decrease of interferences at registration of output signals of attachable eddy-current converter that rotates together with the rotor. |
