Dakota Digital CMX operation manual Introduction to Coating Measurement CT

Dakota Ultrasonics

Note: CHECK YOUR CALIBRATION! Place the transducer back on the

calibration point. The coating thickness reading should now match the known

thickness. If the thickness is not correct, repeat the steps above.

9.5 Introduction to Coating Measurement (CT)

In the previous sections we’ve discussed how to setup and use the coating feature for use in conjunction with material thickness and flaw and pit detection. The CMX also has the capability to be used for general coating measurements. This measurement mode is called Coating (CT) and can be enabled using the same methods as described in a previous section above.

When the Coating Only (CT) mode is enabled, a two point calibration on the coating samples must be performed. This is to ensure linearity o ver the coating measurement range will be achieved. Important note: If coating measurements will be made with the coating applied to a metal surface, the calibration must be done in the same manner, with the samples coupled to a metal surface. However, if the coating will be measured as a stand alone material, the calibration must be performed the same way.

9.6 Two Point Coating Calibration (CT)

Known Thickness

The following section will demonstrate the two point coating calibration procedure. This example demonstrates a coating thickness range of .040” - .120” ( 1 – 3 mm) as follows:

Note: It’s always handy to carry a set of mechanical calipers to use in conjunction with the CMX for calibration in the field:

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