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CHAPTER TEN
BOLT MATERIAL CALIBRATION
10.1 Why Calibrate?
The preset bolt types in the
MiniMax
contain average factors for the material type.
These are approximate values only. In a tightly controlled application where extreme
accuracy is required, it is necessary to obtain all the information possible about the
fasteners being measured. By calibrating the fasteners, the ultrasonic and physical
lengths of the bolts will match. However, if a field calibration is done, a complete
calibration is not necessary. An important thing to note is the fact that everything
done in the calibration process result in average values. Since a sample of fasteners
will be used in the calibration process, and given the slight differences in material, the
result will always be an average value of that sample.
10.2 Velocity Calibration
A velocity calibration is generally performed by adjusting the velocity in the
MiniMax
to the point where the ultrasonic and physical lengths match. Again, since a sample
of fasteners will be used in this process, the velocities will vary by a very small
amount, thus resulting in an average velocity value. To accurately calibrate the
velocity, a calibrated set of mechanical calipers is required to determine the exact
physical lengths of the fasteners. The following procedure outlines this process.
Calibrating the Velocity
1) Press the
key once to activate the menu items tab. Press the
key
multiple times to tab right, and the
key multiple times to tab left, until the
GEOM
menu is highlighted and displaying the submenu items.
2) Press the
and
arrow keys multiple times to scroll through the sub
menu items until
QUANTITY
is highlighted.
Summary of Contents for MiniMax v2.0
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