M1 ultrasonic on-line corrosion monitoring system is a non immersion monitoring system.Our non-intrusive systems use electromagnetic acoustic transducer sensor technology and wireless data delivery to continuously monitor for pipework metal loss from corrosion or erosion in the most difficult environments. Due to the use of electromagnetic acoustic transducer non-destructive testing methods, the probe and metal parts can be lifted by 4mm during measurement, so there is no need to clean the workpiece and it has no damage to the workpiece itself. In addition, the system can also simultaneously monitor changes in coating thickness to help users better assess the corrosion status and remaining service life of the object.