© PCE Teknik Cihazlar
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7
Measurement
Apply the TT-Gel evenly to the surface to be measured. Place the probe onto the surface covered
with the coupling agent.
7.1
Clean surface
Before the measurement, the surface of the object to be tested should be cleaned of
dust, dirt and rust. Coatings such as paint must also be removed.
7.2
Reducing the roughness
Rough surfaces can cause measurement errors or missing readings. Before the
measurement, the material surface should be made as smooth as possible by grinding,
polishing or using a high-viscosity coupling agent.
7.3
Rough surfaces due to heavy machines
Regular fine grooves which occur, for example, during production with lathe machines
and planers can also cause measurement errors. The corrective measure is the same as
in chapter 7.2. In addition, a better result can be obtained by adjusting the angle using
the silver marking on the centre of the probe head and the fine grooves of the material to
be tested (orthogonal or parallel to the marking).
7.4
Measurement of a round surface
To measure a round surface such as a pipe or an oil barrel, it is important to set the angle
between the silver line of the probe and the axis of the material to be tested. In short, the
mark in the sensor head must be kept parallel or perpendicular to the axis of the material
under test. Slowly move the probe head perpendicular to the axis across the material
under test and the values on the display will change regularly. The lowest reading
displayed is the minimum thickness of the material being measured.
The direction in which the probe is guided depends on the curvature of the material. For
large diameter pipes, the mark in the probe head should be perpendicular to the pipe
axis; for smaller diameter pipes, the mark in the probe head can be parallel or
perpendicular to the material axis. The lowest reading is saved as the measured value.
7.5
Measurement of composite material
When measuring composite shapes (such as pipe elbows), the method described in
chapter 7.4 can be used. However, the measurement must be carried out twice to obtain
two readings. The silver line of the probe must be vertical or parallel to the axis. The lower
value is used as the measured thickness.
7.6
Non-parallel surfaces
To obtain a satisfactory result, the surface of the material to be tested must be parallel or
coaxial to the surface of the sensor, otherwise measurement errors will occur or no
reading will be obtained.
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