Thickness gauging in a hazardous area usually requires a hot work permit or shutting down the plant, resulting in a lot of wasted money in downtime. Cygnus Instruments has developed an ultrasonic thickness gauge which will measure the metal thickness through coatings up to 6mm thick. This technique is used in their latest gauge which has been certified intrinsically safe to EEx ia IIC T2 allowing for accurate thickness measurements to be taken without the need for a hot work permit or for plant shutdown.
Previous ultrasound technology meant that intrinsically safe gauges were not feasible because removing coatings requires either grinding or chipping, both of which will cause sparks.
The gauge can be used to monitor corrosion levels quickly and easily, and from one side only, wherever metal wastage is of concern to the operator.
