Eddy current sensor and tube testing tool having at least one such sensor

Tool for the nondestructive testing of a tube and which can be displaced within the latter, comprising a central rotary body having a longitudinal axis and two centering rings supporting the body in the tube in such a way that the body axis substantially coincides with the tube axis, wherein the central rotary body supports at least one eddy current sensor comprising two transmitter windings and at least one receiver winding arranged symmetrically with respect to a reference plane to be oriented in accordance with a direction substantially perpendicular to a surface to be tested, the transmitter windings being positioned on either side the reference plane and each having a median plane substantially parallel to the reference plane and at least one active portion having a shape substantially complementary to that of the surface, and the receiver winding is oriented perpendicular to the reference plane and placed between the active portions of the transmitter windings and having a median plane forming with the reference plane an angle of approximately 90.degree., wherein the two transmitter windings are connected and wound in such a way that they induce opposing magnetic fields in a spatial zone containing the receiver winding, so that no current flows through the latter when the region of the surface to be tested facing the sensor is fault-free.