MEASUREMENT OF THICKNESSES OF STEEL

摘要

The imaginary-reluctance patterns produced by ac magnetics can be used to correct the real-reluctance scans for lift-off variations allowing a very sensitive measurement of corrosion loss from the painted surfaces of 55-gallon barrels. Variations in steel quality were found to have little effect on the measurements. Other problems in barrel inspection through ac magnetics require investigation. Among these are detection of loss on the stiffening rings on the barrel surfaces. This problem can probably be solved through design of the gap face of the bridge used in ac magnetics.