Patent ID: 8018227

Claim:
A device for measuring the surface level and/or the presence of a molten metal bath in a cooled crystallizer for a continuous casting process, comprising a source of an electromagnetic field, wherein said source of an electromagnetic field is a transmission coil fed with electrical energy at a predetermined frequency, and wherein: said transmission coil is a single transmission coil with a substantially flat shape attached to only a portion of a wall of said crystallizer, substantially astride to a foreseen level of the bath in the crystallizer, having a main axis substantially perpendicular to the main axis of said crystallizer, said coil is energized by an electrical signal at a frequency between 10 to 200 Hertz, and the information on the level and/or the presence of said surface level is obtained by processing a total impedance (Z), as measured on said transmission coil, which acts also as a receiving coil, in order to calculate a contribution to said impedance (Z) of currents induced in walls of the crystallizer, which depend on temperature of the crystallizer and, from said contribution to said impedance (Z), a value of said surface level and/or the presence of the molten metal bath.