A novel speed measurement system in steel industries based on new magnetic contact-less sensor

This paper shows preliminary results of a project based on a new magnetic contact-less sensor that allows strip speed determination in order to improve the control and quality of annealing and tempering processes in steel industries. The system is based on the measurement of the reactance variation that an inductance based on an amorphous wire core shows in the presence of very low magnetic fields. A magnetic mark is printed on the steel surface using a magnetic writer and is detected by the inductance sensor situated ahead in the steel line process. This paper shows some results obtained on carbon steel and ferritic stainless steel using markers and sensors situated between 2 and 8 centimetres apart from the steel surface.