Probe Angle - GE USM 36 Series Technical Reference And Operating Manual

Flaw position calculation with angle-beam probes
● Reduced projection distance rPD
Distance from the probe front edge to the position of
the flaw, projected onto the surface.
● Depth d
Distance between flaw position and surface.
When working with angle-beam probes, the USM 36
can calculate the skip distance L up to the next reflec-
tion point as well. This skip distance can be indicated as
the reading LA, LB, or LC in the measurement line.
USM 36

PROBE ANGLE

You can use the function PROBE ANGLE to adjust the
angle of incidence of your probe for the material used.
This value is required for the automatic calculation of
flaw position.
The following settings are possible:
● OFF (the function is turned off)
● 30° ... 90°
You can set the value by coarse adjustment steps or by
fine adjustment (see Section Coarse adjustment and
fine adjustment, page 4-11).
When a setting is selected, the tangent of the angle is
additionally indicated for information below the angle in-
dication.
This value enables a good estimation of the position of
the first reflection after the probe index (sound exit) with
regard to the object thickness of the test block.
Issue 2 (12/2013)
5 Operation
5-45