Monitoring of mechanical sealing.

The monitoring arrangement is for a mechanical sealing system (4) and involves at least two seal in rings (5,6) rotatable relative to each other, determining a seal with their facing surfaces. A piezo-electric monitoring component (11) oversees the seal, emitting signals directed to a location forming an indication of the state of the seal. Receiving devices receive the signals and evaluation devices (12) evaluate the state of the seal on the basis of the emitted and received signals. The piezo-electric component (11) emits ultra-sound waves, which are reflected by the seal and received by the piezo-electric component. On the basis of such received waves, a conclusion can be drawn, based on the intensity of the contacts, as to the state of the contact between the touching ring surfaces, such as wear, pressure force and similar. The degree of gravity of the conclusion can give rise to an alarm.