Pregunta 1
Pregunta
Generally, the best ultrasonic testing method for detecting
discontinuities oriented along the fusion zone in a welded plate
is:
Respuesta
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An angle-beam contact method using surface waves.
-
A contact test using a straight longitudinal wave.
-
An immersion test using surface waves.
-
An angle-beam method using shear waves.
Pregunta 2
Pregunta
An ultrasonic testing instrument that displays pulses
representing the magnitude of reflected ultrasound as a function
of time or depth of metal is said to contain:
Pregunta 3
Pregunta
At a water-to-steel interface the angle of incidence in water
is 7 degrees. The principal mode of vibration that exists in the
steel is:
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-
Longitudinal
-
Shear
-
Both A and B
-
Surface
Pregunta 4
Pregunta
In a liquid medium, the only mode of vibration that exists is:In a liquid medium, the only mode of vibration that exists is:
Respuesta
-
Longitudinal
-
Shear
-
Both A and B
-
Surface
Pregunta 5
Pregunta
In an ultrasonic instrument, the number of pulses produced by
an instrument in a given period of time is known as the:
Pregunta 6
Pregunta
In a basic pulse-echo ultrasonic instrument, the component
that coordinates the action and timing of other components is
called a:
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-
Display unit or CRT.
-
Receiver.
-
Marker circuit or range marker circuit.
-
Synchronizer, clock, or timer.
Pregunta 7
Pregunta
In a basic pulse-echo ultrasonic instrument, the component that
produces the voltage that activates the search unit is called:
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-
An amplifier
-
A receiver
-
Pulser
-
A synchronizer
Pregunta 8
Pregunta
In a basic-pulse-echo ultrasonic instrument, the component that produces the time base line is called a:
Respuesta
-
Sweep circuit
-
Receiver
-
Pulser
-
Synchronizer
Pregunta 9
Pregunta
In a basic pulse-echo ultrasonic instrument, the component
that produces visible signals on the CRT which are used to measure
distance is called a:
Respuesta
-
Sweep circuit
-
Marker circuit
-
Receiver circuit
-
Synchronizer
Pregunta 10
Pregunta
Most basic pulse-echo ultrasonic instruments use:
Pregunta 11
Pregunta
The cathode ray tube screen will display a plan view of the part
outline and defects when using:
Pregunta 12
Pregunta
The incident angles at which 90 degrees refraction of
longitudinal and shear waves occurs are called:
Pregunta 13
Pregunta
Compression waves whose particle displacement is parallel to
the direction of propagation are called:
Respuesta
-
Longitudinal waves
-
Shear waves
-
Lamb waves
-
Rayleigh waves
Pregunta 14
Pregunta
Which of the following modes of vibration are quickly damped
out when testing by the immersion method?
Respuesta
-
Longitudinal waves
-
Shear waves
-
Transverse waves
-
Surface waves
Pregunta 15
Pregunta
The motion of particles in a shear wave is:
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Parallel to the direction of propagation of the ultrasonic beam.
-
Transverse to the direction of beam propagation.
-
Limited to the material surface and elliptical in motion.
-
Polarized in a plane at 45 degrees to the direction of beam propagation.
Pregunta 16
Pregunta
In contact testing, shear waves can be induced in the test material by:
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Placing a X-cut crystal directly on the surface of the materials and coupling through a film of oil.
-
Using two transducers on opposite sides of the test specimen.
-
Placing a spherical acoustic lens on the face of the transducer
-
Using a transducer mounted on a plastic wedge so that sound enters the part at an angle.
Pregunta 17
Pregunta
As frequency increases in ultrasonic testing, the angle of
beam divergence of a given diameter crystal:
Pregunta 18
Pregunta
Which of the following is not an advantage of contact
ultrasonic search units(probes) adapted with lucite shoes?
Respuesta
-
Eliminates most of the crystal wear.
-
Permits adaptation to curved surfaces.
-
Decreases sensitivity.
-
Allows ultrasound to enter a part's surface at oblique angles.
Pregunta 19
Pregunta
In which medium listed below would the velocity of sound be
lowest?
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Air
-
Water
-
Aluminum
-
Stainless Steel
Pregunta 20
Pregunta
A longitudinal ultrasonic wave is transmitted from water into
steel at an angle of 5 degrees from the normal. In such a case the
refracted angle of the transverse wave is:
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Less than the refracted angle of the longitudinal wave.
-
Equal to the refracted angle of the longitudinal wave.
-
Greater than the refracted angle of the longitudinal wave.
-
Not present at all.
Pregunta 21
Pregunta
The velocity of longitudinal waves will be highest in:
Respuesta
-
Water
-
Air
-
Aluminum
-
Stainless Steel
Pregunta 22
Pregunta
In steel, the velocity of sound is greatest in which of the
following modes of vibration?
Pregunta 23
Pregunta
The acoustic impedance is:
Respuesta
-
Used to calculate the angle of reflection
-
The product of the density of the material and the velocity of sound in the material.
-
Found by Snell's law
-
Used to determine resonance values
Pregunta 24
Pregunta
Thin sheet may be inspected with the ultrasonic wave directed
normal to the surface by observing:
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The amplitude of the front surface reflection.
-
The multiple reflection pattern.
-
All front surface reflections
-
None of the above.
Pregunta 25
Pregunta
A diagram in which the entire circuit stage or sections are
shown by geometric figures and the path of the signal or energy by
lines and/or arrows is called a:
Respuesta
-
Schematic diagram
-
Blueprint
-
Block diagram
-
None of the above
Pregunta 26
Pregunta
A hole produced during the solidification of metal due to
escaping gases is called:
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-
A burst
-
A cold shut
-
A flaking
-
a blow hole
Pregunta 27
Pregunta
A discontinuity that occurs during the casting of molten metal
which may be caused by the splashing, surging, interrupted pouring,
or the meeting of two streams of metal coming from different
directions is called:
Respuesta
-
A burst
-
A cold shut
-
Flaking
-
A blow hole
Pregunta 28
Pregunta
The ratio between the wave speed in one material and the wave
speed in a second material is called:
Pregunta 29
Pregunta
The expansion and contraction of a magnetic material under the
influence of a changing magnetic field is referred to as:
Respuesta
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Piezoelectricity
-
Refraction.
-
Magnetostriction
-
Rarefaction
Pregunta 30
Pregunta
The ratio of stress to strain in a material within the elastic
limit is called:
Pregunta 31
Pregunta
A point, line, or surface of a vibrating body marked by absolute
or relative freedom from vibratory motion is referred to as:
Respuesta
-
A node
-
An antinode
-
Rarefaction
-
Compression
Pregunta 32
Pregunta
A quartz crystal cut so that its major faces are parallel to
the Z and Y axes and perpendicular to the X axis is called:
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-
A Y-cut crystal
-
A X-cut crystal
-
A Z-cut crystal
-
A ZY-cut crystal
Pregunta 33
Pregunta
The equation describing wavelength in terms of velocity and
frequency is:
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Wavelength = Velocity x Frequency
-
Wavelength = Z (Frequency x Velocity
-
Wavelength = Velocity / Frequency
-
Wavelength=Frequency + Velocity
Pregunta 34
Pregunta
Which of the following can occur when an ultrasonic beam
reaches the interface of two dissimilar materials?
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-
Reflection
-
Refraction
-
Mode conversion
-
All of the above
Pregunta 35
Pregunta
Of the piezoelectric materials listed below, the most
efficient sound transmitter is:
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-
Lithium sulfate
-
Quartz
-
Barium titanate
-
Silver oxide
Pregunta 36
Pregunta
Of thepiezoelectric materials listed below, the most
efficient sound receiver is:
Respuesta
-
Lithium sulfate
-
Quartz
-
Barium titanate
-
Silver oxide.
Pregunta 37
Pregunta
The most commonly used method of producing shear waves in a
test part when inspecting by the immersion method is:
Respuesta
-
By transmitting longitudinal waves into a part in a direction perpendicular to its front surface.
-
By using two crystals vibrating at different frequencies.
-
By using a Y-cut quartz crystal.
-
By angulating the search tube to the proper angle.
Pregunta 38
Pregunta
Beam divergence is a function of the dimensions of the crystal
and the wavelength of the beam transmitted through a medium, and it:
Respuesta
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increases if the frequency or crystal diameter is decreased.
-
decreases if the frequency or crystal diameter is decreased.
-
increases if the frequency is increased and crystal diameter decreased.
-
decreases if the frequency is increased and crystal diameter is decreased.
Pregunta 39
Pregunta
The wavelength of an ultrasonic wave is:
Respuesta
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directly proportional to velocity and frequency.
-
directly proportional to velocity and inversely proportional to frequency.
-
inversely proportional to velocity and directly proportional to frequency.
-
equal to the product of the velocity and frequency.
Pregunta 40
Pregunta
The fundamental frequency of a piezoelectric crystal is
primarily a function of:
Respuesta
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the length of the applied voltage pulse.
-
the amplifying characteristics of the pulse amplifier in the instrument.
-
the thickness of the crystal.
-
none of the above.
Pregunta 41
Pregunta
Acoustic velocities are primarily described by:
Respuesta
-
density
-
elasticity
-
both A and B
-
acoustic impedance
Pregunta 42
Pregunta
Inspection of castings is often impractical because of:
Pregunta 43
Pregunta
Lamb waves may be used to inspect:
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forgings
-
bar stock
-
ingots
-
thin sheet
Pregunta 44
Pregunta
The resolving power of a search unit is directly proportional
to its:
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-
diameter
-
band width
-
pulse repetition
-
none of the above
Pregunta 45
Pregunta
In the basic pulse-echo instrument, the synchronizer, clock or
timer circuit will determine the instrument's:
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-
pulse length
-
gain
-
pulse repetition rate
-
sweep length
Pregunta 46
Pregunta
The primary requirement of a paintbrush transducer is that:
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all crystals be mounted equidistant from each other.
-
the intensity of the beam pattern not vary greatly over the entire length of the transducer
-
the fundamental frequency of the crystals not vary more than .01%.
-
the overall length not exceed 3 inches.
Pregunta 47
Pregunta
Heat conduction, viscous friction, elastic hysteresis, and
scattering are four different mechanisms which lead to:
Respuesta
-
attenuation
-
refraction
-
beam spreading
-
saturation.
Pregunta 48
Pregunta
Since the velocity of sound in aluminum is approximately 245,000
in/sec, how long does it take for sound to travel through 1 inch of
aluminum?
Respuesta
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1/8 second
-
4 microseconds
-
4 milliseconds
-
1/4 X 100000 seconds
Pregunta 49
Pregunta
When testing a part with a rough surface, it is generally
advisable to use:
Respuesta
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a lower frequency search unit and a more viscous couplant than is used on parts with a smooth surface.
-
a higher frequency search unit and a more viscous couplant than is used on parts with a smooth surface.
-
a higher frequency search unit and a less viscous couplant than is used on parts with a smooth surface.
-
a lower frequency search unit and a less viscous couplant than is used on parts with a smooth surface.
Pregunta 50
Pregunta
Reflection indications from a weld area being inspected by the
angle-beam technique may represent:
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Porosity
-
Cracks
-
Weld bead
-
All three of the above
Pregunta 51
Pregunta
In an A-scan presentation, the horizontal line formed by the
uniform and repeated movement of an electron beam across the
fluorescent screen of a cathode ray tube is called:
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-
A square wave pattern.
-
A sweep line.
-
A marker pattern.
-
None of the above.
Pregunta 52
Pregunta
Which of the following frequencies would probably result in
the greatest amount of attenuation losses?
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1.0 megahertz.
-
2.25 megahertz.
-
5 megahertz.
-
10 megahertz.
Pregunta 53
Pregunta
In general, which waves will travel around gradual curves with
little or no reflection from the curve?
Respuesta
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Transverse waves.
-
Surface waves.
-
Shear waves.
-
Longitudinal waves.
Pregunta 54
Pregunta
To evaluate and accurately locate discontinuities after
scanning a part with a paintbrush transducer, it is generally
necessary to use a:
Pregunta 55
Pregunta
As the impedance ratio of two dissimilar materials increases,
the percentage of sound coupled through an interface of such materials:
Pregunta 56
Pregunta
Low frequency sound waves are not generally used to test thin
materials because of:
Respuesta
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The rapid attenuation of low frequency sound.
-
Incompatible wavelengths.
-
Poor near-surface resolution.
-
None of the above will actually limit such a test.
Pregunta 57
Pregunta
When using two separate search units (one a transmitter, the
other a receiver), the most efficient combination would be:
Respuesta
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A quartz transmitter and a barium titanate receiver.
-
A barium titanate transmitter and a lithium sulfate receiver.
-
A lithium sulfate transmitter and a barium titanate receiver.
-
A barium titanate transmitter and a quartz receiver.
Pregunta 58
Pregunta
In immersion testing, the accessory equipment to which the
search cable and the search unit are attached is called a:
Pregunta 59
Pregunta
In general, discontinuities in wrought products tend to be
oriented:
Respuesta
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Randomly.
-
In the direction of grain flow.
-
At right angles to the entry surface.
-
At right angles to the grain flow.
Pregunta 60
Pregunta
In immersion testing irrelevant or false indications caused by
contoured surfaces are likely to result in a:
Respuesta
-
Broad-based indication.
-
Peaked indication.
-
"Hashy" signal.
-
Narrow-based indication.
Pregunta 61
Pregunta
In contact testing, defects near the entry surface cannot
always be detected because of:
Respuesta
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The far-field effect.
-
Attenuation.
-
The dead zone.
-
Refraction.
Pregunta 62
Pregunta
In cases where the diameter of tubing being inspected is
smaller than the diameter of the transducer, what can be used
to confine the sound beam to the proper range of angles?
Pregunta 63
Pregunta
The maximum scanning speed possible is primarily determined
by:
Respuesta
-
The frequency of the searchunit.
-
Viscous drag problems.
-
The pulse repetition rate of the test instrument.
-
The persistency of the CRT screen.
Pregunta 64
Pregunta
Surface waves are reduced to an energy level of approximately
1/25 of the original power at a depth of:
Respuesta
-
One inch.
-
Four inches.
-
One wavelength.
-
Four wavelengths.
Pregunta 65
Pregunta
To prevent the appearance of the second front surface
indication before the first back reflection when inspecting
aluminum by the immersion method (water is used as a couplant),
it is necessary to have a minimum of at least one inch of
water for every:
Pregunta 66
Pregunta
Increasing the length of the pulse used to activate the search
unit will:
Respuesta
-
Increase the strength of the ultrasound but decrease the resolving power of the instrument.
-
Increase the resolving power of the instrument.
-
Have no effect on the test.
-
Decrease the penetration of the sound wave.
Pregunta 67
Pregunta
Of the following sound wave modes, which one has multiple or
varying wave velocities?
Respuesta
-
Longitudinal waves
-
Shear waves
-
Transverse waves
-
Lamb waves
Pregunta 68
Pregunta
Which of the following would be considered application(s) of
ultrasonic techniques?
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-
Determination of a material's elastic modulus
-
Study of a material's metallurgical structure
-
Measurement of a material's thickness
-
All of the above.
Pregunta 69
Pregunta
The only significant sound wave mode that will travel through
a liquid is:
Respuesta
-
Shear
-
Longitudinal
-
Surface
-
Rayleigh
Pregunta 70
Pregunta
The acoustic impedance of a material is used to:
Respuesta
-
Determine the angle of refraction at an interface.
-
Determine the attenuation within the material.
-
Find the amounts of sound energy reflected and refracted through an interface.
-
Determine the beam spread within the material.
Pregunta 71
Pregunta
Acoustic energy propagates in different modes. Which of the
following represents a mode?
Respuesta
-
Longitudinal wave
-
Shear wave
-
Surface wave
-
All of the above
Pregunta 72
Pregunta
When angle beam contact testing a test piece, increasing the
incident angle until the second critical angle is reached results in:
Respuesta
-
Total reflection of a surface wave.
-
45 degree refraction of the shear wave
-
Production of a surface wave
-
None of the above
Pregunta 73
Pregunta
The simple experiment where a stick in a glass of water appears
disjointed at the water surface illustrates the phenomenon of:
Respuesta
-
Reflection
-
Magnification
-
Refraction
-
Diffraction
Pregunta 74
Pregunta
The crystal thickness and transducer frequency are related. The
thinner the crystal:
Pregunta 75
Pregunta
The random distribution of crystallographic direction in alloys
with large crystalline structure is a factor in determining:
Pregunta 76
Pregunta
The length of the zone adjacent to a transducer in which
fluctuations in sound pressure occur is mostly affected by:
Pregunta 77
Pregunta
The differences in signals received from identical reflectors
at different material distances from a transducer may be caused by:
Respuesta
-
Material attenuation.
-
Beam divergence.
-
Near field effects.
-
All of the above.
Pregunta 78
Pregunta
It is possible for a discontinuity smaller than the transducer to
produce indications of fluctuating amplitude as the search unit is
moved laterally if testing is being performed in the:
Respuesta
-
Fraunhofer zone.
-
Near field.
-
Snell field.
-
Shadow zone.
Pregunta 79
Pregunta
In immersion testing, the near field effects of a transducer
may be eliminated by:
Respuesta
-
Increasing transducer frequency.
-
Use of larger diameter transducer.
-
Using an appropriate water path.
-
Use of a focused transducer.
Pregunta 80
Pregunta
Which of the following may result in a long narrow rod if the
beam divergence results in a reflection from a side of the test
piece before the sound wave reaches the back surface?
Respuesta
-
Multiple indications before the first back reflection.
-
Indications from multiple surface reflection.
-
Conversion from the longitudinal mode to shear mode.
-
Loss of front surface indications.
Pregunta 81
Pregunta
Where does beam divergence occur?
Respuesta
-
Near field.
-
Far field.
-
At the crystal.
-
None of the above.
Pregunta 82
Pregunta
As frequency increases in ultrasonic testing, the angle of
beam divergence of a given diameter crystal:
Pregunta 83
Pregunta
As the radius of curvature of a curved lens is increased, the
focal length of the lens will:
Pregunta 84
Pregunta
When examining materials for planar flaws oriented parallel to
the part surface, what testing method is most often used?
Respuesta
-
Angle beam
-
Through-transmission
-
Straight beam
-
Dual crystal
Pregunta 85
Pregunta
Rayleigh waves are influenced most by defects located:
Respuesta
-
One wavelength below the surface
-
Six wavelengths below the surface
-
Close to or on the surface
-
Three wavelengths below the surface
Pregunta 86
Pregunta
The ultrasonic test method in which finger damping is most
effective in locating a discontinuity is:
Respuesta
-
Shear wave
-
Longitudinal wave
-
Surface wave
-
Compressional wave
Pregunta 87
Pregunta
Lamb waves can be used to detect:
Respuesta
-
Laminar-type defects near the surface of a thin material
-
Lack of fusion in the center of a thick weldment
-
Internal voids in diffusion bonds
-
Thickness changes in heavy plate material
Pregunta 88
Pregunta
The ratio of the velocity of sound in water compared to that
for aluminum or steel is approximately:
Pregunta 89
Pregunta
Which of the following scanning methods could be classified as
an immersion type test?
Respuesta
-
Tank in which the search unit and test piece are immersed
-
Squirter bubbler method in which the sound is transmitted in a column of flowing water
-
Scanning with a wheel-type search unit with the transducer inside a liquid filled tire
-
All of the above
Pregunta 90
Pregunta
In an immersion test of a piece of steel or aluminum, the
water distance appears on the display as a fairly wide space
between the initial pulse and the front surface reflection
because of:
Respuesta
-
Reduced velocity of sound in water as compared to test specimen.
-
Increased velocity of sound in water as compared to test specimen.
-
Temperature of the water.
-
All of the above.
Pregunta 91
Pregunta
What law can be used to calculate the angle of refraction
within a metal for both longitudinal and shear waves?
Respuesta
-
Poisson's Ratio Law
-
Snell's Law
-
Fresnel's Field Law
-
Charles' Law
Pregunta 92
Pregunta
At an interface between two different materials, an impedance
difference results in:
Pregunta 93
Pregunta
When using focused transducers, non-symmetry in a propagated
sound beam may be caused by:
Pregunta 94
Pregunta
Ultrasonic wheel units may be used for which of the following
types of examination?
Respuesta
-
Straight or longitudinal examination
-
Angle-beam or shear wave examination
-
Surface wave or Rayleigh wave
-
All of the above
Pregunta 95
Pregunta
During straight beam testing, test specimens with non-parallel
front and back surfaces can cause:
Respuesta
-
Partial or total loss of back reflection
-
No loss in back reflection
-
A widened (broad) back reflection indication
-
A focused (narrow) back reflection indication
Pregunta 96
Pregunta
In the immersion technique, the distance between the face of
the transducer and the test surface (water path) is usually adjusted
so that the time required to send the sound beam through the water.
Respuesta
-
Is equal to the time required for the sound to travel through the piece.
-
Is greater than the time required for the sound to travel through the test piece.
-
Is less than the time required for the sound to travel through the test piece.
-
None of the above.
Pregunta 97
Pregunta
In a B-scan display, the length of a screen indication from a
discontinuity is related to:
Pregunta 98
Pregunta
Which circuit triggers the pulser and sweep circuits in an
A-scan display?
Respuesta
-
Receiver-amplifier
-
Power supply
-
Clock
-
Damping
Pregunta 99
Pregunta
On an A-scan display, the "dead zone," refers to:
Respuesta
-
The distance contained within the near field.
-
The area outside the beam spread.
-
The distance covered by the front surface pulse width and recovery time.
-
The area between the near field and the far field.
Pregunta 100
Pregunta
On an A-scan display, what represents the intensity of a
reflected beam?
Pregunta 101
Pregunta
Of the following scan types, which one can be used to produce
a recording of flaw areas superimposed over a plan view of the test
piece?
Respuesta
-
A-scan
-
B-scan
-
C-scan
-
D-scan
Pregunta 102
Pregunta
In immersion testing in a small tank, a manually operated
manipulator is used to:
Respuesta
-
Set the proper water path
-
Set the proper transducer angle
-
Set the proper index function
-
Both A and B
Pregunta 103
Pregunta
A 45 degrees shear angle beam transducer produces a wave in
the metal which is polarized:
Respuesta
-
Perpendicular to the direction of propagation and parallel to the entry surface.
-
In the direction of propagation and at 45 degrees to the normal to the entry surface.
-
Perpendicular to the entry surface.
-
Perpendicular to the direction of propagation and at 45 degree to the entry surface.
Pregunta 104
Pregunta
In straight (normal) beam contact testing, a reduction in the
back surface reflection amplitude could indicate:
Pregunta 105
Pregunta
In an automatic scanning immersion unit, the bridge or
carriage serves to:
Respuesta
-
Support the manipulator and scanner tube and to move it about transversely and longitudinally.
-
Control the angular and transverse positioning of the scanner tube.
-
Control the vertical and angular positioning of the scanner tube.
-
Raise and lower the transducer.
Pregunta 106
Pregunta
When adjusting the flaw locating rule for a shear wave weld
inspection, the zero point on the rule must coincide with the:
Pregunta 107
Pregunta
A special scanning device with the transducer mounted in a
tire- like container filled with couplant is commonly called;
Respuesta
-
A rotating scanner
-
An axial scanner
-
A wheel search unit
-
A circular scanner
Pregunta 108
Pregunta
Which best describes a typical display of a crack whose major
surface is perpendicular to the ultrasonic beam?
Pregunta 109
Pregunta
Compensation for the variation in echo height related to variations
in discontinuity depth in the test material is known as:
Pregunta 110
Pregunta
Which of the following is a reference reflector that is not
dependent on beam angle
Pregunta 111
Pregunta
During a straight beam ultrasonic test a discontinuity
indication is detected which is small in amplitude compared
to the loss in amplitude of back reflection. The orientation
of this discontinuity is probably:
Respuesta
-
Parallel to the test surface.
-
Parallel (plus or minus 5 degrees) from the test surface.
-
Parallel to the sound beam.
-
Such that complete loss of back reflection will result.
Pregunta 112
Pregunta
A discontinuity is located having an orientation such that its
long axis is parallel to the sound beam. The indication from such a
discontinuity will be:
Respuesta
-
Large in proportion to the length of the discontinuity.
-
Small in proportion to the length of the discontinuity.
-
Representative of the length of the discontinuity.
-
Such that complete loss of back reflection will result.
Pregunta 113
Pregunta
Gas discontinuities are reduced to flat discs or other shapes
parallel to the surface by:
Respuesta
-
Rolling
-
Machining
-
Casting
-
Welding
Pregunta 114
Pregunta
In which zone does the amplitude of an indication from a given
discontinuity diminish exponentially as the distance increases?
Respuesta
-
Far field zone
-
Near field zone
-
Dead zone
-
Fresnel zone
Pregunta 115
Pregunta
A smooth flat discontinuity whose major plane is not
perpendicular to the direction of sound propagation may be indicated by:
Respuesta
-
An echo amplitude comparable in magnitude to the back surface reflection.
-
A complete loss of the back surface reflection.
-
An echo amplitude larger in magnitude than the back surface reflection.
-
All of the above.
Pregunta 116
Pregunta
Using a pulse-echo technique, if the major plane of a flat
discontinuity is oriented at some angle other than perpendicular
to the direction of sound propagation, the result may be:
Respuesta
-
Loss of signal linearity
-
Loss or lack of a received discontinuity echo
-
Focusing of the sound beam
-
Loss of interference phenomena
Pregunta 117
Pregunta
As transducer diameter decreases, the beam spread:
Respuesta
-
Decreases
-
Remains the same
-
Increases
-
Becomes conical in shape
Pregunta 118
Pregunta
A set of standard reference blocks with the same geometrical
configuration and dimensions other than the size of the calibration
reflectors, e.g., flat bottom holes, is called a set of:
Respuesta
-
Distance/amplitude standards.
-
Area/amplitude standards.
-
Variable frequency blocks.
-
Beam spread measuring blocks.
Pregunta 119
Pregunta
The angle at which 90 degree refraction of a longitudinal
sound wave is reached is called:
Respuesta
-
The angle of incidence.
-
The first critical angle.
-
The angle of maximum reflection.
-
The second critical angle.
Pregunta 120
Pregunta
Which of the following controls the voltage supplied to the
vertical deflection plates of the CRT in an A-scan UT setup?
Respuesta
-
Sweep generator
-
Pulser
-
Amplifier circuit
-
Clock timer
Pregunta 121
Pregunta
Attenuation is a difficult quantity to measure accurately,
particularly in solid materials, at the test frequencies normally
used. The overall result usually observed includes other loss
mechanisms which can include:
Respuesta
-
Beam spread
-
Couplant mismatch
-
Test piece geometry
-
All of the above
Pregunta 122
Pregunta
The vertical linear range of a test instrument may be
determined by obtaining ultrasonic responses from:
Respuesta
-
A set of distance-amplitude reference blocks.
-
Steel balls located at several different water path distances.
-
A set of area-amplitude reference blocks.
-
All of the above.
Pregunta 123
Pregunta
Large grains in a metallic test specimen usually result in:
Pregunta 124
Pregunta
The total energy losses occurring in all materials is called:
Respuesta
-
Attenuation
-
Scatter
-
Beam spread
-
Interface
Pregunta 125
Pregunta
Delay-tip(stand-off)type contact search units are primarily
used for:
Respuesta
-
Defect detection.
-
Sound wave characterization.
-
Thickness measurement of flaw detection in thin materials.
-
Attenuation measurements.
Pregunta 126
Pregunta
Acoustical lenses are commonly used for contour correction.
When scanning the inside of a pipe section by the immersion method,
which of the following lens types would be used?
Respuesta
-
Focused cup
-
Convex
-
Concave
-
Variable pitch
Pregunta 127
Pregunta
When the incident angle is chosen to be between the first and
second critical angles, the ultrasonic wave generated within the
part will be:
Respuesta
-
Longitudinal
-
Shear
-
Surface
-
Lamb
Pregunta 128
Pregunta
The attenuation of energy within a material in the far field
of the ultrasonic beam may be expressed as the:
Respuesta
-
Arithmetic mean
-
Geometrical average
-
Exponential average
-
Exponential decay
Pregunta 129
Pregunta
For aluminum and steel the longitudinal velocity is approximately
_________ the shear velocity:
Respuesta
-
Equal to
-
Twice
-
One-half of
-
Four times
Pregunta 130
Pregunta
Water travel distance for immersion inspections should be:
Pregunta 131
Pregunta
The electronic circuitry that allows selection and processing
of only those signals relating to discontinuities that occur in
specific zones of a part is called:
Pregunta 132
Pregunta
When conducting a contact ultrasonic test, the "hash" or
irregular signals that appear in the CRT display of the area
being inspected could be caused by:
Respuesta
-
Fine grains in the structure.
-
Dirt in the water couplant.
-
Coarse grains in the structure.
-
A thick but tapered back surface.
Pregunta 133
Pregunta
In inspecting a 4-inch diameter threaded steel cylinder for
radial cracks extending from the root of the threads, it would be
preferable to transmit:
Respuesta
-
Shear waves at an angle to the threads.
-
Longitudinal waves from the end of the cylinder and perpendicular to the direction of the thread roots.
-
Surface waves perpendicular to the thread roots.
-
Shear waves around the circumference of the cylinder.
Pregunta 134
Pregunta
In an immersion inspection of raw material, the water travel
distance should be:
Respuesta
-
Exactly 3 inches.
-
Equal to 3 inches (plus or minus 1/2 inch).
-
Equal to the water travel distance used in setting up on the reference standards.
-
Equal to the thickness of a material.
Pregunta 135
Pregunta
The angle formed by an ultrasonic wave as it enters a medium
of different velocity than the one from which it came and a line
drawn perpendicular to the interface between the two media is called:
Pregunta 136
Pregunta
The process of adjusting an instrument or device to a reference
standard is referred to as:
Pregunta 137
Pregunta
An electron tube in which a beam of electrons from the cathode
is used to reproduce an image on a fluorescent screen at the end of
the tube is referred to as:
Respuesta
-
An amplifier tube
-
A pulser tube
-
A cathode ray tube
-
A sweep tube
Pregunta 138
Pregunta
A grouping of a number of crystals in one search unit, with
all contact surfaces in the sample plane, and vibrating in phase
with each other to act as a single transducer is called a:
Respuesta
-
Focusing crystal
-
Crystal mosaic
-
Scrubber
-
Single plane manipulator
Pregunta 139
Pregunta
The scattering of the ultrasonic energy of an ultrasonic beam
due to reflection from a highly polished surface is called:
Respuesta
-
Angulation
-
Dispersion
-
Refraction
-
Rarefaction
Pregunta 140
Pregunta
The angle of reflection is:
Respuesta
-
Equal to the angle of incidence.
-
Dependent on the couplant used.
-
Dependent on the frequency used.
-
Equal to the angle of refraction.
Pregunta 141
Pregunta
The angular position of the reflecting surface of a planar
discontinuity with respect to the entry surface is referred to as:
Pregunta 142
Pregunta
A short burst of alternating electrical energy is called:
Respuesta
-
A continuous wave
-
A peaked DC voltage
-
An ultrasonic wave
-
A pulse
Pregunta 143
Pregunta
In ultrasonic testing, the time duration of the transmitted
pulse is referred to as:
Pregunta 144
Pregunta
The phenomenon by which a wave strikes a boundary and changes
the direction of its propagation within the same medium is referred
to as:
Respuesta
-
Divergence
-
Impedance
-
Angulation
-
Reflection
Pregunta 145
Pregunta
The change in direction of an ultrasonic beam when it passes
from one medium to another whose velocity differs from that of
the first medium is called:
Respuesta
-
Refraction
-
Rarefaction
-
Angulation
-
Reflection
Pregunta 146
Pregunta
The coated inside surface of the large end of a cathode ray
tube which becomes luminous when struck by an electron beam is called:
Respuesta
-
An electron gun
-
An electron amplifier
-
A CRT screen
-
An electron counter