In X-ray tubes with a rotating anode, the shielding of the stator is obtained by a first conductive layer that is deposited on the external wall of an insulating bell-shaped part and has an electrical discontinuity, and by a second conductive layer that is deposited on the internal wall of an insulating cup-shaped or bowl-shaped part, the bell and the bowl encasing the stator and thus creating an electrostatic screen against the high frequency oscillations that result from the "crackling" of the tube. The device can be applied to X-ray tubes for radiology instruments.