Olympus nortec 600, Руководство пользователя

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DMTA-10040-01EN, Rev. E, February 2018
Chapter 5 230
For the calibration steps in these applications, you can obtain the best results if you
are familiar with your calibration standard (tube). It is strongly recommended that
you review the calibration standard before each inspection application and mark the
null or flaw positions on the probe’s polyethylene tubing. To do this, you can place the
probe with tubing along the outside of the calibration standard. With the probe
placed next to the null or flaw location, make a reference mark on the polyethylene
tubing (at the calibration standard entrance) using a permanent marker or tape (see
Figure 5-153 on page 230).
Figure 5 ‑ 153 An example of marking the probe positions
5.4.1 ECT Pitting, Wear, and Cracks — NORTEC 600D Model
In this application, an eddy current “bobbin” probe is used to identify localized, small
defects such as pitting, wear, and cracks in tubing made of nonferromagnetic alloys.
ECT is a noncontact method in which the probe is excited with an alternating current,
inducing eddy currents in the part being inspected (see Figure 5-154 on page 231).
Any discontinuities or material property variations that change the eddy current flow
in the part are detected as potential defects by the probe. This technique is suitable for
the detection and sizing of metal discontinuities such as corrosion, erosion, wear,
pitting, baffle cuts, and wall loss. ECT is also suitable for detecting cracks in
nonferrous materials such as austenitic stainless steel (for example, types 304 and
316), brass, copper-nickel, titanium, copper-fin, and Inconel.
NOTE
Flaw on calibration standard
Mark on probe’s polyethylene tubing