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1 Learn the meaning of the following words and word-combinations word groups:

observing the electromagnetic response, an expanding number of electromagnetic and
magnetic test, to detect near-surface cracks and corrosion in metallic objects, depth of
penetration, flux leakage testing, to detect broken strands of wire, surface-breaking cracks,
amount of radiation emerging, to determine thickness or composition of material, different
alignment of the beam, the incident beam, exceed the actual thickness, a latent image of
varying densities, to be detected by prolonging the exposure, before commencing a
radiographic examination, to examine the component with one's own eyes, to eliminate any
possible external defects. to grind, to obtain a smooth finish, internal defects, delaminations
and planar cracks are difficult to detect.

2 Read and translate text:

Methods of Nondestructive testing

Electromagnetic Testing (ET), as a form of nondestructive testing, is the process of
inducing electric currents or magnetic fields or both inside a test object and observing the
electromagnetic response. If the test is set up properly, a defect inside the test object creates a
measurable response.
The term "Electromagnetic Testing" is often intended to mean simply Eddy-Current
Testing (ECT). However with an expanding number of electromagnetic and magnetic test
methods, "Electromagnetic Testing" is more often used to mean the whole class of
electromagnetic test methods, of which Eddy-Current Testing is just one.
Common Methods of Electromagnetic Testing:
 Eddy-Current Testing (ECT) is used to detect near-surface cracks and corrosion in
metallic objects such as tubes and aircraft fuselage and structures. ECT is more commonly
applied to nonferromagnetic materials, since in ferromagnetic materials the depth of
penetration is relatively small.
 Remote field testing (RFT) is used for nondestructive testing (NDT) of steel tubes and
pipes.
 Magnetic flux leakage testing (MFL) is also used for nondestructive testing (NDT) of
steel tubes and pipes. At present RFT is more commonly used in small diameter tubes and
MFL in larger diameter pipes over long travel distances.
 Wire rope testing is MFL applied to steel cables, to detect broken strands of wire.
 Magnetic particle inspection (MT or MPI) is a form of MFL where small magnetic
particles in the form of a powder or liquid are sprayed on the magnetized steel test object and
gather at surface-breaking cracks.
 Alternating Current Field Measurement (ACFM) is similar to eddy current applied to
steel. Its most common application is to detect and size cracks in welds. Description from the
company that developed it.
 Pulsed eddy current enables the detection of large-volume metal loss in steel objects
from a considerable stand-off, allowing steel pipes to be tested without removing insulation.

Radiographic Testing (RT), or industrial radiography, is a nondestructive testing (NDT)
method of inspecting materials for hidden flaws by using the ability of short wavelength
electromagnetic radiation (high energy photons) to penetrate various materials.

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