Checkline TI-44N - Manual (Page 8)

6.0 S ETUP F OR M EASURING T HICKNESS O F M ATERIALS
O THER T HAN S TEEL
The TI-44N Thickness Gauge is supplied from the factory set for an acoustic velocity
of 5930 m/sec for the measurement of Steel. To measure the thickness of any other
material, the acoustic velocity must be changed. When checking the built-in calibra-
tion disc, the gauge should display the “Equivalent Value” listed in the Table in sec-
tion 6.1, instead of 0.197" or 5.0 mm for steel.
To determine the proper acoustic velocity for measurement of the non-steel material,
refer to the Acoustic Velocity Selection Table in section 6.1. After determining the
proper acoustic velocity, the gauge must be changed to this new value as described
in section 6.3 Changing The Acoustic Velocity Settings.
If you do not know the type of material to be measured or the material type is not
listed in the Acoustic Velocity Selection Table, refer to section 6.2, Setup Of Gauge
When Acoustic Velocity is Unknown
TI-44N Operating Instruction Guide
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7.0 T AKING M EASUREMENTS
After setting the gauge for the correct acoustic velocity for the material to be meas-
ured or retaining the factory preset value of 5930 m/sec for measurement of steel, the
gauge is ready to take measurements.
A coupling fluid must be used between the probe and the sample to obtain measure-
ments. A two (2) ounce bottle is supplied with the gauge. We highly suggest using
this water soluble couplant. Long-term use of petroleum-based couplants (grease,
oil, etc.), salt water or chemical solvents will eventually damage the probe.
Additional bottles of coupling fluid are available from the gauge supplier.
1. Turn the power on by pressing the POW key.
2. Place a small amount of coupling fluid on the calibration disc located on the
face of the instrument.
3. Grasp the probe by the holding the spring-loaded centering shell and place it on
the calibration disc. Press the shell down until it contacts the surface.
4 . Confirm that the calibration disc measures 0.197" (± 0.001") or
5.0 mm (± 0.01mm) or the “Equivalent Value” as found in the Acoustic Velocity
Selection Table for non-steel materials.
5. Place a small amount of coupling fluid on the surface to be measured, press
probe onto the surface and proceed as indicated in step 3 above.
The gauge will display the thickness of the material or wall along with the Good
Coupling Indicator. The Indicator will remain on the display while the probe is in
contact with the sample.
If the Good Coupling Indicator is not displayed, then the measurement was not
successful and should be repeated. If this problem persists then the surface may
not be in acceptable condition for measurement. Refer to Preparing The Surface
For Measurement, section 7.2.
Good Coupling
Indicator
TI-44N Operating Instruction Guide
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