Lesson 12: Guided Wave Method Flashcards
What is the waveguide?
a. Structure being tested.
b. Lucite tool to direct the wave.
c. The transducer housing.
d. Frequency chosen to determine the direction of the guided wave.
a. Structure being tested.
Which of the following types of transducers cannot be used to generate guided waves?
a. Conventional straight-beam transducers.
b. Immersion transducers.
c. EMAT transducers.
d. Magnetostrictive transducers.
b. Immersion transducers.
Guided wave analysis is:
a. similar to TOFD.
b. very comparable to PA.
c. as simple as a single mode of propagation.
d. similar to analysis of a mode-converted shear wave.
c. as simple as a single mode of propagation.
One downside of EMAT transducers is:
a. couplant is needed.
b. they must be adhesively attached to the surface.
c. they do not work with magnetic piping.
d. relatively low efficiency.
d. relatively low efficiency.
Guided waves include:
a. compression, shear, and surface waves.
b. only mode-converted shear waves.
c. surface waves guided by a guide tool.
d. surface and lamb waves.
d. surface and lamb waves.
The speed at which a specific point on a wave moves is called:
a. dispersive wave propagation.
b. wave velocity.
c. phase velocity.
d. group velocity.
c. phase velocity.
The velocity of a guided wave is:
a. consistent with conventional UT rules.
b. varying based on frequency used.
c. controlled by material properties alone.
d. different based on waveguide geometry.
d. different based on waveguide geometry.
Magnetostriction can only occur in:
a. ferromagnetic material.
b. anisotropic material.
c. nonmagnetic material.
d. tubular material.
a. ferromagnetic material.
Which is not an advantage of guided wave?
a. The ability to test long pipe sections.
b. The ability to locate and size small discontinuities.
c. No need for scanning.
d. Greater sensitivity with low frequency.
a. The ability to test long pipe sections.
The set of curves of possible guided wave mode velocities plotted together is called a:
a. boundary constraint curve.
b. group velocity curve.
c. phase velocity curve.
d. dispersion curve.
d. dispersion curve.
Using guided waves in frequencies 10 kHz to 100 kHz:
a. reduces sensitivity compared to localized testing.
b. enhances discontinuity detection sensitivity.
c. is about the same as for other UT modes.
d. adds the ability to improve discontinuity sizing.
a. reduces sensitivity compared to localized testing.
How far can guided waves effectively propagate?
a. 10 to 12 ft (3 to 3.7 m) a typical pipe length.
b. 300 to 400 ft (91 to 122 m).
c. No definite number as there are many factors to be considered.
d. Propagation is limited only by part geometry.
c. No definite number as there are many factors to be considered.
What is the frequency range for using guided waves on thicker test objects?
a. 1 kHz to 10 kHz.
b. 10 kHz to 100 kHz.
c. 10 kHz to 200 kHz.
d. 10 kHz to 500 kHz.
b. 10 kHz to 100 kHz.
What are the guided wave modes?
a. Longitudinal, shear, and surface.
b. Surface, lamb, and plate.
c. Longitudinal, axial, axisymmetric, and SH-type modes.
d. Longitudinal, torsional, flexural, SH-type, and lamb-type modes.
d. Longitudinal, torsional, flexural, SH-type, and lamb-type modes.
In a dispersion curve, the wave modes represent a relationship between:
a. time and distance.
b. velocity and attenuation.
c. velocity and frequency.
d. frequency and attenuation.
c. velocity and frequency.
