Inputting Test-Piece Properties - GE Phasor CV Operating Manual

2. Setting Up for Phased Array Measurement
Determining and Inputting the Probe-Index-Point
to Wedge-Front-Edge Distance (PROBE-WDGE
GEO-WEDGE FRONT)
A line scribed on the side of the wedge (see
corresponds with the probe's index point. The mea-
surement from this line to the wedge's front edge is the
WEDGE FRONT dimension. This value must be deter-
mined and input before inputting the ORIGIN OFFSET
(see next section), which allows the instrument's display
to compensate when a probe is offset (by a guide ring, for
instance) a fixed distance from the inspection target.
Step 1: Activate the RESULTS1 Submenu in the DIS-
PLAY Menu as set one of the READING values to PA as
described in Section 3.2.
NOTE: Gates must be on.
Step 2: Activate the WDGE GEO Submenu (located in
the PROBE Menu) by pressing
Step 3: Couple to a block with a known reflector (as
shown in Figure 2-4). Move the probe until the probe-
wedge front is aligned over the reflector (and the reflector
is detected). Observe the displayed value of PA.
Step 4: Press next to the selection WEDGE FRONT.
Step 5: Turn the Function Knob until the displayed value
of PA reads zero.
Step 6: Repeat this process to confirm that the displayed
value of PA equals zero when the front edge of the probe
wedge is aligned with the known reflector. Continue to
adjust the WEDGE FRONT value if required.
NOTE: The WEDGE FRONT (WF) and ORIGIN OFF-
SET (OO) settings directly effect the frame of reference
from which all projection RESULTS (such as PA) are
measured. When a value of 0 is input for both WF and
OO, all projection results are measured with respect to
the probe index point (PIP). When 0 is input for OO and
a numerical value for WF, all projection measurements
are with respect to the wedge front. When numerical
values are input for both WF and OO, all projection
results are measured with respect to the user-defined
origin.
Inputting Probe/Wedge Offset Distance (PROBE-
OFFSET-ORIGIN OFFSET)
When an installation calls for a probe/wedge assembly to
be offset a fixed distance from an inspection target, the
value of the offset (which is typically equal to the width
of an installed guide ring) must be manually measured
and input. This allows the instrument to compensate for
Page 20
Figure 2-4)
below it.
the offset and adjust the display accordingly
Be sure to also measure and input the WEDGE FRONT
dimension before setting ORIGIN OFFSET.
Step 1: Activate the OFFSET Submenu (located in the
PROBE Menu) by pressing
Step 2: Manually measure the distance that the front of
the wedge is offset from the target.
Step 3: Press next to the selection ORIGIN OFF-
SET.
Step 4: Turn the Function Knob until the displayed value
matches the manually measured dimension.
Step 5: The value will be set to the last one displayed.
Defining the Probe Element Orientation with
Respect to the Wedge (PROBE-WDGE DAT-ELEM
1 POS)
Markings on the probe body will indicate the location of
element 1 and the direction in which additional elements
are arranged. The orientation of the probe's elements,
with respect to the wedge's geometry, is defined using the
ELEM 1 POS function. See
Step 1: Activate the WDGE DAT Submenu (located in
the PROBE Menu) by pressing
Step 2: Press next to the selection ELEM 1 POS.
Step 3: Continue to press
to select one of the following:
LOW END -- The position of Element 1 is indicated
on the probe body at a location corresponding to the
low (thinnest) side of the wedge. Remaining ele-
ments are arranged towards the high (thickest) side
of the wedge. (Figure
HIGH END -- The position of Element 1 is indicated
on the probe body at a location corresponding to the
high (thickest) side of the wedge. Remaining ele-
ments are arranged towards the low (thinnest) side
of the wedge. (Figure
Step 4: Probe element orientation will be defined as last
displayed. Recalculation of delay laws is required.
2.4

Inputting Test-Piece Properties

To correctly determine the physical location at which a re-
flector occurs, the test piece's thickness and material type
(indicating shear and longitudinal velocities of sound in the
test piece) must be input. These parameters directly affect
the displayed range and the calculated trig values.
(Figure
below it.
Figures 2-5 and 2-6.
below it.
or turn the Function Knob
2-5)
2-6)
PHASOR XS Operating Manual
2-4).