A servomotor is designed to generate a precise movement of a mechanical component, for example an industrial valve, according to an external control. A servomotor is thus a motorized system capable of achieving predetermined positions, then maintaining them. The position is, in the case of a rotary servomotor, a corner position, and, in the case of a linear servomotor, a distance position. The start-up and preservation of the predetermined position are controlled by the external control.
One important parameter for the proper operation of the servomotor is its sealing. Indeed, in certain fluid pressurized environments, such as for example in nuclear power plants, the servomotors must be able to withstand high steam pressures, for example up to 5 or 6 bars.
The servomotor, although considered to be sealed, can have sealing flaws due for example to a defective joint or a poorly adjusted electrical cable in a cable inlet of the servomotor. If the servomotor is not completely sealed, pressurized steam risks penetrating the inside of the servomotor and damaging the electrical equipment of the servomotor.
It is known to regularly change the joints of the servomotor to offset these sealing problems. However, the joints can be poorly assembled. It is also possible for the sealing flaw not to be related to the joint, but for example a cracking of the housing of the servomotor. Changing the joints therefore does not make it possible to ensure that the servomotor is sealed in all cases.
It thus appears necessary to be able to simply and reliably assess the sealing of a servomotor housing.
The invention proposes a method making it possible to achieve this aim.