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Maintenance and warranty
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14
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13.5. Laminated material, composite material
It is impossible to measure uncoupled laminate materials
because ultrasonic waves cannot penetrate the uncoupled
space. Since ultrasonic waves cannot transmit at a constant
velocity in composite materials, instruments that measure
thickness by ultrasonic reflection are not suitable for
measuring laminated materials and composite materials.
13.6. Effects of oxide layer on metal surface
Some metals can produce a dense oxide layer on the
surface, such as aluminum. This layer of oxide is tightly
bonded to the substrate with no obvious interface. However,
the transmission speed of ultrasonic waves in these two
substances is different, thus resulting in errors. Different
thickness of oxide layer causes different errors, to which the
user shall pay attention. You can carve a piece of the same
material with a micrometer or caliper as sample to calibrate the
instrument.
13.7. Use and selection of coupling agent
Coupling agent is used to transfer high-frequency ultrasonic
energy between the probe and the tested material.
Inappropriate type or improper usage may cause errors or
failed measurement with lable of coupling agent flashing. It
should be used in an appropriate amount and applied evenly.
Coupling agent is usually applied to the surface of tested
material. When the temperature is high, coupling agent is
applied to the bottom of probe.
It is important to choose the right type of coupling agent. For
materials with smooth surface, coupling agents of low viscosity
(such as randomly mixed coupling agent, light machine oil,
etc.) are suitable. For rough surface, vertical surface and top
surface or aluminum, higher-viscosity coupling agents (such
as glycerin creams, greases, etc.) can be used.
Coupling agents of various formulations are available in many
places.
14.1. Probe protection:
The surface of the probe is acryl resin, which is sensitive to
grooves on rough surface and should be handled with care in
use. When measuring rough surface, please reduce the slide
of probe on the surface; the surface temperature of the
measured object should not exceed 60 °C (high temperature
probe for high temperature surface), otherwise the probe will
fail to work; oil and dust on the surface will gradually age the
cable in probe, and cause it to break. So clean the dirt on cable
after use.
a. Cleaning of case:
Alcohol and diluents have a corrosive effect on case,
especially the window, so when cleaning case, gently wipe it
with a little water.
b.Cleaning of test samples:
When using random test sample to calibrate the instrument,
apply coupling agent to prevent it from rusting. After finishing,
please wipe coupling agent off test sample. Do not drip sweat
on test sample when the temperature is high. If it is not in use
for a long time, apply a little fat oil on the surface of random test
sample (all kinds of anti-rust oil will also do). When using it
again, please wipe anti-rust oil off test sample first and then
start to perform.
c. Note: remember to avoid collision, humidity, etc.
14.2. Maintenance
If any of the following problems occur, please contact our
company or agent:
a. The instrument device is damaged and cannot measure
with no output.
b. LCD does not work properly.
c. In normal use, the error is too large.
d. Keyboard operation is out of order or in confusion.
