Device and method for measuring condensation and/or advance of corrosion

A device for measuring degradation of a surface layer of a conduit, comprising:

• an insulator extending around the surface layer on the conduit;
• a first conductor and a second conductor at a distance of the first conductor, said first and second conductor being arranged such that at least a portion of the insulator lies between the conduit and the first conductor and between the conduit and the second conductor,
• wherein, the first and second conductors are arranged in a longitudinal direction of the conduit at a longitudinal distance from each other, or the first and second conductors overlap only partially at an outer end thereof and have an electrically insulating strip disposed between the overlapping portions of the first and second conductors such that there is no direct contact between the two;
• and
• at least one measuring instrument configured to determine an impedance value between the first and second conductors which is representative of the impedance of the surface layer underneath said portion of the insulator.

A method for measuring condensation on and/or advance of corrosion of a conduit, comprising:

• arranging an insulator around the conduit;
• arranging a first conductor and a second conductor such that at least a portion of the insulator lies between the conduit and the first conductor and the second conductor, the portion extending along a longitudinal direction of the conduit such that the first conductor forms a first pole of a capacitor, the second conductor forms a second pole of the capacitor, and the portion therebetween comprises a capacitive coupling between the first pole and the second pole,
• wherein, in a longitudinal direction of the conduit, the first and second conductors are arranged at a longitudinal distance from each other along the longitudinal direction of the conduit, or the first and second conductors overlap only partially at an outer end thereof and have an electrically insulating strip disposed between the overlapping portions of the first and second conductors such that there is no direct contact between the two;
• and
• determining a value which is representative of the capacitive coupling.