NDT Systems TG400, Руководство оператора

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Quick Start B-Scan Setup
Assumptions:
Stock Transducer - PX506
0.500" Thick Pipe/Plate
Assembly:
Connect and secure cable to Phoenix bottom
Connect Lemo end to Scanner
Assure transducer is flush to recessed into swivel
sled. Recess should not be more than 0.004" This
is about the thickness of 1 piece of scotch tape.
(0.1mm) below sled surface. If the probe is
recessed too much there will be excess crosstalk
which will make scan setup more difficult. The
transducer is loosened and secured by the 2 screws
used in mounting of the swivel sled. The transducer is removed by placing a thin
screwdriver in a groove at the base of the transducer as shown in the figure. Once the
transducer is secure in it’s proper position re-secure the two screws on the side.
Calibration: Note - Quick Reference for the Ultrasonic Calibration is shown on back side of
unit.
1. The first thing when calibrating a unit which can display an A-
Trace is to set you Gain, Range and Delay on a clean reference
sample such as a step block. This will assure you have a good
signal on screen, from the thickest area to the thinnest area of
your sample.
2. Go to the SETUP Menu and select the PX506 if it is shown. If
not select TG506. This should set the instrument up in general
terms. Adjustments for a particular probe now will have to be
made.
3. Set Range to about 0.750"
4. Set Delay to about 0.000
5. Set probe on thin section of test block. For instance 0.250" Do
not worry yet about the thickness reading. Adjust the gain to be sure you see the first
echo for the 0.250. Move the probe to 0.500" & then to 0.100" to be sure you are
observing an echo from the test block. All the waveforms should remain on screen
assuming you do not exceed the 0.750" set in the prior step.
6. Once the waveform is on screen in the proper positions we will need to adjust the IP-
BLOCK control which is in the GATES menu. The IP-BLOCK is used to ignore noise
from crosstalk or surface roughness. Set the bar for the IP-BLOCK just past the steady
noise signal if there is one. Otherwise, set the probe on a test block at about 0.100" and
move the IP-BLOCK to stop just in front of the 0.100" echo.
7. Now we are ready to calibrate. Press the PROBE ZERO button the front of the gage.
The Gage will then tell you to place the probe on the ZERO DISC (on the side of the