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Trang 1

indication on the cathode ray tube (CRT) which 6 tpresents the far boundary of the material being

ested is called: ~-a, hash

b the initial pause c the main bang

d the back surface reflection

H-2-8 7 In immersion testing, the position of the search unit is often varied to transmit sound into the test part at various angles to the front surface Such a procedure is referred to as: yo: a angulation "" b dispersion c reflection testing d refraction F-45.10; H-3-12 8

The cable that connects the ultrasonic instrument to

the search unit is specially designed so that one

conductor is centered inside another The technical

eos name for such a cable is: ty a BX cable i b conduit aa c coaxial cable 9, 4 d ultrasonic conductor cable-grade 20 j H-3-13., Fig 3-9

4 The process of comparing an instrument or device

with a standard is called: angulation calibration attenuation Qo fp F-43.37 Another name for a compressional wave is: , a Lamb wave ab shear wave longitudinal wave piransverse wave F-43.9; H-2-5 correlation 10 Levei I Questions Ultrasonic Method Another name for Rayleigh waves is: a shear waves b longitudinal waves c transverse waves d surface waves H-2-32

A materiai used between the face of a search unit and the test surface to permit or improve the transmission of ultrasonic vibrations from the search unit to the

material being tested is called: ⁄ a wetting agent a couplant 4 phe Tung MA 2 an acOustic transmitter a lubricant Bap H-3-21 The piezoelectric material in a search unit which vibrates to produce ultrasonic waves is called a: a backing materia: b Lucite™ wedge c crystal d couplani H-2-7 Ultrasonic testing of material where the search unit is in direct contact with the material being tested may be:

Trang 2

Ultrasonic Method, Level I Figure 1 SSS LLL ¬—— \

_ 11 The search unit shown in Figure 1 is used for:

surface wave testing angle beam testing immersion testing straight beam testing aaa p F-43.5; H-3-17 14 15 NOTE: Using Figure 2, answer questions 16 through 20 |

The amount of beam divergence from a crystal is

primarily dependent on the:

a type of test

b tightness of crystal backing in the search unit c frequency and crystal size

d pulse length

D-107; H-2-30; J-240

When an ultrasonic beam passes through the interface

between two dissimilar materials at an angle, a new

angle of sound travel takes place in the second

material due to: attenuation rarefaction compression refraction aorp F-43.15; H-2-19, H-2-21; J-236

12 Which of the following search units would contain

the thinnest quartz crystal? 16 Figure 2 illustrates a contact test on an 20 cm (8 in.)

; aluminum block A discontinuity is located 15 cm

a a! MHz search unit (6 in.) from the front surface The screen

b a 5 MHz search unit representation for this is shown to the right What

c a 15 MHz search unit does indication A represent?

d a 25 MHz search unit

D-106; E-223; H-3-20 a initial pulse or front surface indication

- b first discontinuity indication

13 A 25 MHz search unit would most likely be used c first back surface reflection

during: d none of the above

E-231; F-43.31, F-47.2, 6; J-245,

a straight beam contact testing b immersion testing

c angle beam contact testing

Trang 3

¢ 2, what does indication B represent? i} pulse or front surface indication discontinuity indication

k surface refiection the above

E-231; F-47.2 6 F-43.31; J-245 e 2 what does indication C represent”

Kond back surface reflection

Prst discontinuity indication

‘gecond discontinuity indication

® first back surface reflection

E-231; F-43.31, F-47.2, 6; J-245

® In Figure 2, what does indication D represent?

a first discontinuity indication

b second indication of the discontinuity c first back surface reflection

d second back surface reflection

E-231; F-43.31, F-47.2, 6; J-245 In Figure 2, what does indication E represent?

? a first discontinuity indication

: b second discontinuity indication

c first back surface reflection

d second back surface reflection

E-231; F-43.31, F-47.2, 6; J-245

21 The velocity of surface waves is approximately the velocity of shear waves in the same material a two times b four times c l2 d io F-43.8 NOTE: Using Figure 3, answer questions 22 through 26 Figure 3 | " 25 mm (1 in.) 7 co 76 mm ; si mm 2 in (3in.) Aluminum Water L we 24 25 26 21

Ditrasonic Metioh Level]

Figure 3 illustrates an immersion test of a 76 mm (3 in.) block of aluminum with a discontinuity located

51 mm (2 in.) below the sutface The screen pattern

is Shown aiso What does indication A represent? Assume no sweep delay is used _

first front surface indication Initial pulse

first discontinuity indication first back surface reflection

F-43.31, F-47.2, 3 4: H-4-6, H-2-9; J-245

Đo

œzĐ®

In Figure 3 indication B represents the: first front surface indication

initial pulse

first back surface reflection first discontinuity reflection

F-43.31, F-47.2, 3, 4; H-4-6, H-2-9; J-245

Bop

In Figure 3, indication C represents the: a first front surface indication

b first discontinuity indication c first pack surface reflection d second front surface indication

F-43.31, F-47.2, 3, 4; H-4-6, H-2-9; J-245

In Figure 3 indication D represents the:

a first discontinuity indication b first back surface reflection c second front surface indication c second discontinuity indicauon

F-43.31, F-47.2, 3, 4: H-4-6, H-2-9; J-245

In Figure 3 the distance between indications A and B represents:

a the distance from the front surface of the aluminum block to the discontinuity b the distance from the front surface of the

aluminum block to the back surface of the aluminum block c the water distance from the search unit to the aluminum block c none of the above F-43.31 F-47.2, 3, 4; H-4-6, H-2-9; J-245

Under most circumstances, which of the following

Trang 4

Ultrasonic Method, Level I 28 30 31 32

Which of the following materials of the same alloy is 34 When the motion of the particles of a medium is most likely to produce the greatest amount of sound parallel to the direction of propagation, the wave attenuation over a given distance? being transmitted is called a:

a a hand forging a longitudinal wave

b a coarse-grained casting b shear wave

c an extrusion c surface wave

d the attenuation is equal in all materials d Lamb wave

D-93; E-221; F-48.10; H-2-28; J-238 E-210

In contact testing, the entry surface indication is 35 When the motion of the particles of a medium is sometimes referred to as: transverse to the direction of propagation, the wave

being transmitted is called a: a the initial pulse

b the main bang or transmitter pulse a longitudinal wave

c both a and b b shear wave

d none of the above , c surface wave

H-2-8 d Lamb wave

E-210

A screen pattern containing a large number of low-

level indications (often referred to as “hash”) could 36 ‘25 million cycles per second” can aiso be stated as: be caused by: V2 : a 25 kHz a a crack b 2500 kHz b a large inclusion c 25 MHz c coarse-grained material d 25 uHz d a gas o¬cket H-2-5 E-221; F-47.14; J-238

` 37 Moving a search unit over a test surface either

A test method employing two separate search units on manually or automatically is referred to as: opposite surfaces of the material being tested is

called: a scanning

* b attenuating

a contacttesting _ c angulating

b surface wave testing d resonating

¢ through-transmission testing E-250

d Lamb wave testing

H-4-9 "38 A term used in ultrasonics to express the rate at which sound waves pass through various substances is: The number of complete waves which pass a given

point in a given period of time (usually Í s) is a frequency

referred to as the: b velocity

c wavelength

a amplitude of a wave motion d pulse length

Dd pulse length of a wave motion t-43.9

ở Írequencv of a wave motion 7T

d wavelength of a wave motion ( 39.7 When a vertical indication has reached the maximum H-2-5 signal height which can be displayed or viewed on

the CRT of an ultrasonic instrument, the indication is

The boundary between two different materials which said to have reached its: are in contact with each other is called:

a distance amplitude height

a a rarefactor b absorption level

b a refractor c vertical level

¢ an interface d limit of resolution

d a marker A-E-500

E-216

Trang 5

trasonic testing technique in which the

lucer element is not parallel to the test surface is

angle beam testing immersion testing c contact testing d: through-transmission testing H-4-9 Using Figure 4, answer questions 41 through 43 Figure 4 Water ; Metal 41 42 43

In Figure 4, angle 1 (9,) is called: 48 a the angle of incidence

b the angle of reflection c the angie of refraction d none of the above

F-43.15 In Figure 4, angie 2 (6,) is called:

a the angle of incidence

b the angle of reflection c the angle of refraction d none of the above

F-43.15

In Figure 4, angle 3 (0,) is called: 49

a the angle of incidence

b the angle of reflection c the angle of refraction d none of the above

F-43.15

Most commercial ultrasonic testing is accomplished using frequencies between: 1 and 25 kHz i 1 and 1 000 kHz B 0.2 and 25 MHz K15 and 100 MHz bi F-43.1: B-3-20 11 In an A-scan presentation, the horizontal base line 46 47 | Ultrasonic Method, Level ] represents:

the amount of reflected ultrasonic sound energy the distance traveled by the search unit

the elapsed time or distance none of the above

aor

F-43.29

In an A-scan presentation, the amplitude of vertical indications on the screen represents the:

a amount of ultrasonic sound energy returning to the search unit b distance traveled bv the search unit

c thickness of material being tested

d elapsed time since the ultrasonic pulse was generated

F-43.29

Which of the following test frequencies would

generally provide the best penetration in a 30 cm (12 in.) thick specimen of coarse-grained steel? a 1 MHz b 2.25 MHz c 5 MHz d 10 MHz F-48.2

Ina basic ultrasonic test pattern (A-scan) for contact testing (assuming no sweep delay is used), the initial pulse:

a is the high indication on the extreme left side of the screen that represents the entry surface of the inspected part

b is the first pulse that occurs near the right side of

the screen and represents the Opposite boundary of the inspected part

c iS an indication that appears and disappears during Screening

d is aiways the second pulse from the left on the viewing screen

H-2-8; J-242 An ultrasonic test using a straight beam contact

search unit is being conducted through the thickness

of a flat part such as a plate This test should detect:

a laminar-type flaws with major dimensions parallel

to the rolled surface

b transverse-type flaws with major dimensions at right angles to the rolled surface

c radial flaws with major dimensions along length

but radially oriented to the rolled surface

Trang 6

f ee ee

Ultrasonic Method, Level I

50 In ultrasonic testing, a liquid coupling medium between the crystal surface and the part surface is necessary because:

a lubricant is required to minimize wear on the crystal surface

b an air interface between the crystal surface and the

part surface would almost completely reflect the ultrasonic vibrations

c the crystal will not vibrate if placed directly in contact with the surface of the part being inspected d the liquid is necessary to complete the electrical

circuit in the search unit

51 Entry surface resolution is a characteristic of an ultrasonic testing system which defines its ability to:

Yar doe

a detett discontinuities oriented in a direction

parallel to the ultrasonic beam

b detect discontinuities located in the center of a

forging containing a fine metallurgic stfiÈffffe

c detect minute surface scratches

d detect discontinuities located just beneath the entry

surface in the part being tested

A-E-317; F-43.1; H-3-13 52 During ultrasonic testing by the immersion method, it

is frequently necessary to angulate the search unit when a discontinuity is located in order to:

a avoid a large number of back reflections that could interfere with a normal test pattern

b obtain a maximum response if the discontinuity is

not originally oriented perpendicular to the

ultrasonic beam

¢ obtain the maximum number of entry surtace

reflections

d obtain a discontinuity indication of the same height as the indication from the flat bottom hole in a

reference block :

A-E-214; F-46.17, F-46.19, E-47.13 33 All other factors being equal, which of the following

modes of vibration has the greatest velocity? shear wave transverse wave surface wave longitudinal wave anc op D-18; F-43.8; H-2-18 Foe men 54 56 57 58 59

n the area amplitude ultrasonic standard test blocks, the flat bottom holes in the blocks are:

a all of the same diameter

b different in diameter, increasing by 0.4 mm

(0.016 in.) increments from the No “1” block to the No “8” block

c largest in the No “1” block and smailest in the

No “8” block

d drilled to different depths from the front surface of

the test block

A-E-217; H-3-20; H-5-4 A-E-214; F-48.3; H-3-21 (5) In immersion testing, verification that the search unit

is normal to a flat entry surface is indicated by:

a maximum reflection from the entry surface b elimination of water multiples

c proper wavelength

d maximum amplitude of the initial pulse

F-46.17 A piezoelectric material can:

a convert a mechanical strain to an electrical output b convert an electrical pulse to a mechanical strain

c be used in the construction of search units

d be all of the above

E-44.1 Sound waves of a frequency beyond the hearing

range of the human ear are referred to as ultrasonic

waves or vibrations, and the term embraces all

vibrational waves of frequency greater than approximately: 2 kHz 200 kHz i 20 000 Hz i 2 MHz , o0 Œbp D-2; H-2-5 The velocity of sound waves is primarily dependent on: a the pulse length b the frequency

c the material in which the sound is being transmitted and the mode of vibration d none of the above

D-18; F-43.9; H-2-17 A disadvantage of using natural quartz in a search

unit is that:

a it will dissolve in water

b it is the least effective generator of ultrasonic energy of all commonly used materials c it is mechanically and electrically unstable d it easily loses it operating characteristics as it ages

Trang 7

gre most efficient generators of ultrasonic

§ most efficient receivers of ultrasonic

low mechanical impedance

` F-44.2; H-3-14 ary purpose of reference blocks is to: > ˆ

A the operator in obtaining maximum back lections

ain the greatest sensitivity possible from an

instrument

‘obtain a common reproducible signal

Fd none of the above 68

` H-3-22

When testing by the surface wave method, patches of

oil or dirt on the surface may:

block the progress of all sound "

attenuate the sound have no effect on the test

- cause both an attenuation of sound and indications on the screen aod op D-263 63 In immersion testing, the most commonly used couplant is: a water b oil c glycerine d alcohol E-222; H-3-22 69

64 The piezoelectric material in the search unit:

a converts electrical energy to mechanical energy b converts mechanical energy to electrical energy c both a and b

d neither a nor b

H-2-7

65 Which of the following frequencies will produce the shortest wavelength pulse? a 1 MHz b 5 MHz c 10 MHz d 25 MHz H-2-16 13 Of using a ceramic transducer in search 66 d temperatures as high as 700 °C 67

‘Ultrasonic Methog, ‘Level I

The angle of incidence is:

greater than the angle of reflection

less than the angle of reflection

qual to the angle of reflection hot related to the angle of reflection

Qaowrn

H-A-1 On many ultrasonic testing instruments, an operator

conducting an immersion test can remove that portion of the screen presentation that represents water distance by adjusting a:

Trang 8

Ultrasonic Method, Level I

= 74 The gradual loss of sonic energy as the ultrasonic

on Figure 6 vibrations travel through the material is referred to as: a reflection b refraction c reproducibility d attenuation ` F-43.22; H-2-26; J-238

75 A term used to describe numerous small indications on the cathode ray tube screen resulting from test part structure, numerous small discontinuities, or both is often referred to as: nt art I ain

70 Figure 6 is an illustration of a typical: a multiple back reflections

b multiple front reflections

a A-scan presentation c hash

b B-scan presentation d resonance

c C-scan presentation H-4-33; J-246

|

| d D-scan presentation -

L E-251; F-46.5; J-242 76 When testing a plate, increasing the frequency of an

ultrasonic longitudinal wave will result in:

a an increase in its velocity

Figure 7 b a decrease in its velocity

c no change in its velocity

d a reversal in its velocity

E-214 77 Ultrasonic waves transmitted into and received from

the test material in the form of repetitive bursts of

acoustic energy is called:

a pulse echo testing

b continuous wave testing c resonance testing d none of the above

71 Figure 7 is an illustration of a typical: F-43.28; J-241

a, A-scan presentation 78 Metal blocks which contain one or more drilled holes

b B-scan presentation to simulate discontinuities are called:

c C-scan presentation :

d D-scan presentation a scrubbers

E-251; F-46.4; J-242 b crystal collimators

aR tS ¢ Single plane angulators

72 A search unit with a frequency greater than 10 MHz d reference blocks

will most likely be used during: E-273; J-262

a a straight beam contact test of aluminum ingot 79 If the major dimensions of a discontinuity in a 15 cm b an angle beam contact test of a steel pipe: (6 in.) thick aluminum plate lie parallel to the entry

c asurtace wave contact test of a metallic plate surface at a depth of 76 mm (3 in.), it will be best

d an immersion test detected by:

F-46.8; H-2-14

a straight beam test an angie beam test a surface wave test a Lamb wave test

flat bottom holes F-48.11

concave-surface holes

convex-surface holes

conical-shaped holes

bài

Trang 9

Ultrasonic Method, Level I

H The presence of a discontinuity will not produce a 85 Which of the following discontinuities located ý €.điscontinuity mdication on the CRÍT screen 15 cm (6 in.) from the entry surface would result in

using the: the largest CRT indication if all factors except

disconunuity surface condition and orientation are the

beam testing method same?

wave testing method

iin-beam testing method a a 2 mm (0.08 in.) diameter flat-surfaced fugh-transmission testing method discontinuity whose major face is at an angle of

E-232: H-4-9; j-249 75° from the direction of sound beam propagation

b a 2mm (0.08 in.) diameter rough-surfaced

A of a discontinuity cannot be determined discontinuity whose major face is at an angle of

i using the: ì 75° from the direction of sound beam propagation

F c a2 mm (0.08 in.) diameter flat-surfaced

F straight beam testing method discontinuity whose major face is perpendicular to through-transmission testing method the direction of sound beam propagation

re angle beam testing method d a2 mm (0.08 in.) diameter rough-surfaced yd immersion testing method discontinuity whose major face is parallel to the

E-249; J-249 direction of sound beam propagation

F-45-22 When inspecting coarse-grained material, which of

the following frequencies will generate asound wave 86 Search units constructed with a plastic wedge or that will be most easily scattered by the grain standoff between the transducer element and the test

structure? piece are commonly used for:

a | MHz a dual transducer strarght beam contact testing

b 2.25 MHz b angle bear contact testing

c 5 MHz ¢ surface wave contact testing

d 10 MHz d all of the above

F-48.30 H-3-16, H-3-17

83 Which of the following search units would contain 87 A search unit containing three or more individual

the thickest crystal? transducer elements is often referred to as:

a a 1 MHz search unit a a dual transducer

b a5 MHz search unit b a sandwich transducer

c a 15 MHz search unit ¢, a mosaic transducer

d a 25 MHz search unit d none of the above

H-3-20 F-44.11

84 When performing a surface wave test, indications 88 Sound can be focused by means of special curved

may result from: adapters located in front or the transducer element

These adapters are referred to as: a surface discontinuities

b oi] on the surface a scrubbers

c dirt on the surface b acoustic lenses

d all of the above c angle beam adapters

F-45.11 d single plane adapters

F-44.6; H-3-17 89 A test method in which the parts to be inspected are

Trang 10

91 92 93 94 a od : Ultrasonic Method, Level I

A separate time base line imposed on the viewing

screen of some ultrasonic testing instruments that permits measurement of distances is often referred to as: an initial pulse 5 a time/distance line a marker a sweep line Ao oF & H-2-14, H-3-6, H-4-20; J-242 A term used to describe the ability of an ultrasonic

testing system to distinguish between the entry surface response and the response of discontinuities

near the entry surface is: Figure 8 Immersed Transducer SSS | Convex Surface sensitivity penetration segregation resolution aac op F-44.5, F-46.8; H-3-13 95

The phenomenon whereby an ultrasonic wave changes direction when the wave crosses a boundary between materials with different velocities is called: refraction reflection penetration rarefaction 96 aoc op B-26; E-217

In a test where the transducer is not perpendicular to the inspection surface, the angle of incidence is equal

iO: ’

a the angle of refraction d the angle of reflection c the shear wave angle

d half the shear wave angle _ 97,

E-217 The product of the acoustic velocity of sound in a material and the density of the material is the factor that determines the amount of reflection or

‘ransmission of ultrasonic energy when it reaches an interrace This term is called: 4 acoustic impedance 98 veiocity wavelength penetration eo E-215 16

often referred to as the:, :

In transmitting energy into the part shown in

Figure 8, the ultrasonic beam will:

a diverge (spread out) through the part

b converge (focus in to a point) through the part

c transmit straight through the part - d not enter the part

H-2-38 Ultrasonic waves that travel along the surface of a

material and whose particle motion is elliptical are called: a shear waves b transverse waves c longitudinal waves d Rayleigh waves - F-45 sẻ The interference field near hen face of ‘ transducer i is - eg ty oe a Fresnel zone b acoustic impedance c exponential field d phasing zone F-44.12

Trang 11

- Ultrasonic Methhd, Level I formula used to calculate the angle of refraction (53m2 circuit generates a burst of alternating voltage h & material is called: at is applied to the sending transducer? a pulser hofer’s law b receiver-amplifier c damping d clock H-2-24 » J-242

aterial with a given veiocity when frequency is (1 hich circuit coordinates electronic operation of the ed, the wavelength will: entire ultrasonic instrument system? a damping b receiver-amplifier € clock d power supply F-43.9 J-242

s hich circuits electronicaliy amplify return signals 107 A plan view display or recording of a part under

from the receiving transducer and often modify the examination is called: Signals into a form suitable for display?

a a C-scan display

a pulser circuits b an A-scan display

b marker circuits c an X-axis plot

c timer circuits d a strip chart recording

d receiver-amplifier circuits F-43.34

J-242

108 Ultrasonic data which is presented in a form

102 What is the most common type of data display used representative of the cross section of the test for ultrasonic examination of welds? specimen is calied:

a an A-scan display a an A-scan presentation

b a B-scan display b a B-scan presentation

c a C-scan display c a C-scan presentation

d an X-Y plot d an X-Y plot:

F-43.29 H-3-8

(i0a)wien is a plot of signal amplitude versus time? 109 What type of ultrasonic examination uses wheel-type

search units that eliminate the use of a tank?

a an A-scan display

b a B-scan display a through-transmission testing

c a C-scan display b contact testing

d none of the above c resonance testing

5-241 d immersion testing

ầ J-258

(104) ich circuits modify the return signal from the

receiving transducer into a form suitable for display (110) n addition to other functions, a probe manipulator in on an oscilloscope or other output device? a mechanical immersion-scanning unit permits:

a pulser a use of the through-transmission technique

b receiver-amplifier b use of high scanning speeds

c clock c detection of obliquely-oriented discontinuities

d sweep d utilization of less skilled operators

J-242 D-325

Trang 12

Ultrasonic Method, Level I

II] A type of data presentation most likely to be used with a high speed automatic scanning system is:

an A-scan presentation

a velocity versus amplitude plot a C-scan presentation

a plot of echo height versus depth

(Tne component in a conventional immersion system

t hat spans the width of the immersion tank is called: Đo ơb H-3-7 a an articulator b a bridge c a manipulator d a search tube H-3-12

(113)wich component in an ultrasonic immersion system is used to adjust and maintain a known transducer angle? - a carriage - 8 manipulator a search tube an index system aagpnp F-46.1

114 An amplitude type gate is necessary for all: a shear wave examinations

b longitudinal wave examinations - iulomatic examinations I - Manual examinations Gs = F-43.35 115 When a C-scan recording is used to produce a

permanent record of an ultrasonic test, the

information displayed is typically the discontinuity’s: a, depth and size

b depth, orientation, and size c location and depth

d 'ocation and size (plan view)

H-3-48 122

- 16 Rough entry surface conditions can result in: a a loss of echo amplitude from discontinuities > an increase in the width of the front surface echo c both a and b

d none of the above

F-45.15 123 117 As the grain size increases in a material, its principal

effect in ultrasonic testing is on the: velocity of sound attenuation acoustic impedance angle of refraction a b d F-45.3 18 118 In straight beam pulse echo testing 119 (20% the velocity of a lon ao ơ=e ; 8 discontinuity with a rough reflecting surface perpendicular to the incident wave will have what effect on the detected signal in comparison to a smooth flat bottom hole of the same size? a increase it b decrease it c have no effect on it d decrease the width of the pulse of it F-45.22 Ultrasonic vibrations can be propagated only in the

longitudinal mode in which of the following media? a machine oil b aluminum c ice d beryllium H-2-6 gitudinal mode wave in a given homogeneous material is 0.625 cm/ns at 13 mm

(0.5 in.) below the surface, what is the velocity at

51 mm (2 in.) below the surface?

a '/s the velocity at 13 mm (0.5 in.) b '/2 the velocity at 13 mm (0.5 in.)

c the same as the velocity at 13 mm (0.5 in.) d none of the above

H-2-17

Ifa 5 MHz transducer is substituted for a 2.25 MHz

transducer, what would be the effect on the

wavelength of a longitudinal mode wave produced in the test specimen?

the wavelength would be longer ¬

the wavelength would remain constant : the wavelength would be shorter

the wavelength would vary directly with the

acoustic impedance Ce

Trang 13

Ultrasonic Method, Level I " 124, Another name for Fresnel Zone is: (1304 B-scan display shows the relative:

a Fraunhofer Zone a distance a discontinuity is from the transducer and

bs near field its through-dimension thickness

" b distance a discontinuity is from the transducer and

Zone its length in the direction of transducer travel

F-44.12 c cross sectional area of a discontinuity above a predetermined amplitude

tion Is a: d none of the above

: F-43.33

tdisplav characteristic

test material parameter ` 131 Surface (Rayleigh) waves traveling on the top face of

transducer characteristic a block: form of testing

F-43.22 a are not reflected from a sharp edge corner

b are reflected from a sharp edge corner

26 For discontinuity geometries other than flat, the echo c travel through the sharp edge corner and are

amplitude is usually from that observed reflected from the lower edge

for a flat defect, of similar orientation perpendicular d are absorbed by a sharp edge corner

to the sound beams H-2-32

a identical 132 Surface (Rayleigh) waves are more highly attenuated b increased by: c decreased d elongated a acurved surface F-45.24 b a heavy couplant c a thin couplant 127 What must be done to evaluate discontinuities that are d both a and b

oriented at an angle to the entry surface so that the H-2-29

sound beam will strike the piane of the discontinuity

at right angles? 133 The velocity of sound in a material is dependent upon the:

a change the frequency

b grind the surface a frequency of the wave

c angulate the search unit b wavelength

d increase the gain c Material properties

F-47.13 d vibration cycle

F-43.16 2me pulser circuit in an ultrasonic instrument is used

to: 134 To vary or change the wavelength of sound being

used to test a part, you would change the:

a, control the horizontal and vertical sweep

b activate the transducer a sound wave frequency

c contro] transducer timing between transmit and b diahister of the transducer

sweep c electrical pulse voltage

d generate markers that appear on horizontal sweep d pulse repetition rate

F-43.38 D-2

(293 A-scan CRT display which shows a signal both 135 Ultrasonic vibrations are commonly used to: above and below the sweep line is called:

a examine materials for discontinuities

a a video display b examine materials for thickness

b a RF display ¢ examine materials for mechanical properties

¢ an audio display d all of the above

d a frequency modulated display D-2

D-165

Trang 14

Ultrasonic Method, Level I

136 Which of the following has the longest Fresnel zone? a 13 mm (0.5 in.) diameter | MHz b 13 mm (0.5 in.) diameter 2.25 MHz c 28.5 mm (1.125 in.) diameter | MHz d 38 mm (1.5 in.) diameter 2 MHz D-55

When contact testing, if the ultrasonic instrument is

set with an excessively high pulse repetition rate,

which of the following may occur?

the screen trace will become too light to see the time-base line will become distorted

the initial pulse will disappear

ghost or “phantom” indications will appear on

screen during scanning eo ợp D-157 138 The advantages of immersion testing include which of the following?

inspection speed increased

ability to control and direct sound beams - adaptability for automated scanning all of the above

oP

a

J-258

(139)Longitudinal wave velocity in water is approximately 1⁄4 the velocity in aluminum or steel Therefore the minimum water path should be:

a four times the test piece thickness b '/2 the test piece thickness

c '/4 the test piece thickness plus 6 mm (0.25 in.) d none of the above

H-4-5; J-258

140 In immersion testing, a wetting agent is added to the water to:

adjust the viscosity

help eliminate the formation of air bubbles prevent cloudiness none of the above nO OF H-3-22

141 The formula used to determine the fundamental resonant frequency is: a & = V/T b F = V/2T ce F=T/V d F=VT D-106; F-43.36

142 If frequency is increased, the wavelength will: a decrease (be shorter)

b increase (be longer)

c remain the same but velocity will increase d remain the same but velocity will decrease

¥F-43.9; H-3-19 e variable in distance amplitude calibration block construction is the:

a drilled hole size

b drilled hole point angle

c metal distance above the drilled hole

d angle of the drilled hole to block longitudinal axis H-5-7; J-264

hen setting up a distance amplitude correction curve using 3 flat bottom holes, sometimes the hole closest to the transducer gives less of a response than one or both of the other two This could be caused

by:

Inconsistent surface of the calibration block near field effects

incorrect hole geometry all of the above

and

tT

pP

J-239, J-263

145 Most ferrous and nonferrous welds may be ultrasonically tested using a frequency range of: 25-100 kHz 200-500 kHz 1-2.25 MHz 3-6 MHz 10-20 MHz oaomr fh — s X al Re

146 The product of the material density and the velocity

of sound within that material is referred to as: acoustic impedance near field acoustic attenuation ultrasonic beam distribution vibrational index œ Q.Gœ ŒP F-45.1: H-2-35 147 A straight beam contact search unit consists of which

of the following basic components? case crystal, mount, and backing case, crystal, backing und plastic wedge case, crystal, backing, and acoustic lenses all of the above

aoa

Fe

F-43.6

Trang 15

152 153 150 151

pmersion testing to remove the second waict

ection from between the entry surface signal and

sé first back refiection, you should:

e the repetition rate ase the frequency ase the sweep length

rease the water path

a given incident angle as the frequency of the ansducer increases, the refracted angle:

increases b decreases

c stays the same d cannot be determined

Both longitudinal and shear waves may be

simultaneously generated in a second medium when the angie of inaidence is:

between normal and the first critical angle between the first and second critical angles past the second critical angle

only at the second critical angle

aAaowrp

H-2-25 In immersion testing, when the sound beam strikes a concave surface, the sound beam tends to: a converge b diverge c Stay the same d mode convert H-2-38

Penetration of ultrasonic waves in a material is normally the function of test frequency used Which of the following frequencies would provide the greater depth of penetration? a 1 MHz b 2.25 MHz c 5 MHz d 10 MHz H-3-21 Generally speaking certain piezoelectric materials exhibit better properties than others Which of the following materials is considered the most efficient receiver of ultrasonic energy? a quartz b ceramic c barium titanate d lithium sulfate H-3-14 21 F-46.10 H-2-24

Ultrasonic Method, fevel I 154 Refracted energy will assume a new direction of 156 157 158 159 propagation when the is changed principle angle reflected angle Critical angle incident angle a.%O 7t F-43.15 › The loss of energy as it propagates through material

is the result of beam: interference atlenuation absorption - reflection mo ơe F-43.22 In selecting a suitable couplant, which of the

following characteristics would not affect the selection?

- mode of propagation desired

- Material surface finish and temperature operating frequency of the transducer - chemical properties of the couplant

aor

p

J-179: Which of the following could be caused by excessive surface roughness of the material being tested? a a loss of echo amplitude from discontinuitics

within the material

an increase in the width of the initial pulse both a and hb

d none of the above

đâ

F-45.15

Which of the following are reasons for using

reference or calibration standards?

a they provide a measure of the test systems performance b they provide a method for Standardizing the test system c they provide a common basis for expressing test results d all of the above H-5-3

Trang 16

Ultrasonic Method, Level J

160 Ifa discontinuity is oriented at an angle other than

16 _

162

90° to the sound beam, the results may be a:

a loss of signal linearity

b joss or lack of Signal reflected from the discontinuity c focusing of the sound beam

d loss of interference phenomena

H-4-33 - A device that transforms electrical pulses into mechanical and vice versa utilizes:

a Snell’s law

b piezoelectric Principles c mode conversion principlés d none of the above

H-2-7

Whenever an ultrasonic incident angle is set at 5° from normal:

a the refracted wave is mode converted b the refracted wave is the same mode as the incident wave

c the refracted wave will have two components, one of which will be the same mode as the incident

wave

d itis impossible to determine mode(s) of refracted wave without more information L-3-28 fa discontinuity is located in the Fresnel ornear ield region of a sound beam:

ad the larger the discontinuity, the larger the amplitude of the reflected signal b the closer to the surface the discontinuity is

located, the larger will be the amplitude of reflected signal

c in immersion testing, the amplitude of Signal will increase as the water path decreases

d in immersion testing, the amplitude of reflected

signal may increase or decrease as water path decreases

L-2-12

A transducer is vibrating at a frequency and injecting ultrasonic energy through water into a steel specimen: a the sound wavelength is the same in both the water and the steel

b the sound frequency in the water is less than the sound frequency in steel

c the sound wavelength is not the same in both the water and the steel d the sound frequency in the water is greater than the sound frequency in steel L-1-53 Figure 9 15° - — ee —Ố 165 When a longitudinal sound wave strikes a water-stee] interface at an angle of incidence of 15°, (see Figure 9); a b all the sound energy ig reflected back into the water at an angle of 15°

part of the sound energy is reflected at 15° and part is refracted into the steel at an angle of less than 15° it part of the Sound energy is reflected at 15° and pant is refracted along the water-stee] interface - Part of the sound energy is reflected at 15° and part is refracted into the Steel at an angle greater than

1§°

L-3-30

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