ACS A1208, Руководство по эксплуатации

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Ultrasonic thickness gauge A1208
Operation Manual
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ACOUSTIC
CONTROL
SYSTEMS
Please perform the testing again after thorough cleaning the contact place from corrosion. Always remove rough edges and
corrosion from the TO, as this increases the measurement accuracy and allows to increase the service life of the PT.
To test circular objects, please follow some important steps. To measure the wall thickness of a pipe, especially of pipes
with small diameter, please use more viscous liquids than transformer oil or water. Apply more liquid to the contact place. The
screen dividing the vision blocks of the separated-combined transducer shall be positioned across the pipe axis. The light strip
at the end of the transducer is located along the working surface diameter. Press the transducer to the pipe wall and observe
the device readings, then slowly tilt the transducer within the cross-section plane of the pipe in both sides. Please mind how-
ever, you have to roll the transducer along the pipe wall and do not slide along the wall. When the transducer deviates from
the neutral position the device readings will increase. Commonly the readings are minimal in the position where the transducer
touches the pipe walls in the middle of its operating surface, i.e. when the longitudinal transducer axis crosses the pipe axis.
When the transducer highly deviates from this position the readings increase explosively. As the correct value of the measured
thickness please take the smallest stable reading of the device when the PET contacts the pipe wall in the middle of the
operating surface.
1.1.1.2 Measurements using a combined transducer
As soon as the PT touches the surface of the TO in a fraction of a second the reliable ultrasonic contact of the transducer
and TO is established. The first readings appear on the screen. Theses readings may differ insignificantly on pipes with small
diameters when the transducer is shaking. On flat objects the readings are stable.
When measuring flat metallic objects with the thickness 4 to 5 mm and less do not use a very thin coating of contact liquid,
i.e. do not press the transducer to the surface and do not rub on the surface. It is enough to press slightly for the thickness gauge
to start indicating the measurement result. From this moment the readings do not change essentially.
When the thickness of a flat object is more than 20 mm please ensure the transducer is well pressed to the surface.
The pipe wall thickness measurement is especially easy to perform, as you do not have to align the transducer with the
generating line of the pipe. It is also not necessary to rock the transducer on the pipe to find the smallest measured value. It is
enough to place the middle of the operating surface of the transducer on the generating line of the pipe approximately. Please
always us a thick liquid, e.g. mineral fat or lithol.
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