NDT UT LEVEL 2 Study Guide

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NDT UT LEVEL 2 Study Guide
2013-01-29 23:49:50
NDT Ultrasonics Shearwave UT Level

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  1. 1) The following sound wave mode has multiple or varying wave
  2. 2) The following would be considered applications of ultrasonic techniques:
    • the determination of a materials elastic modulus, the study of a materials
    • metallurgical structure, and the measurement of a materials thickness.
  3. The only significant sound wave mode that will travel through a liquid
    A Longtitudinal Wave
  4. The acoustic impedance of a material is used to:
    • Determine the relative amounts of
    • sound energy coupled through and reflected at an interface.
  5. The simple experiment where a stick in a glass of water appears
    disjointed at the water surface illustrates the phenomenon of:
  6. The crystal thickness and transducer frequency are related.
    • The thinner the
    • crystal: 
the higher the frequency.
  7. The random distribution of crystallographic direction in alloys with
    large crystalline structure is a factor in determining:
    • The acoustic noise levels, the selection of a test frequency, and the scattering of
    • sound.
  8. The length of the zone adjacent to a transducer in which fluctuations in
    sound pressure occur is mostly affected by:
the frequency of the transducer
    • and the diameter of the transducer.
  9. The differences in signals received from identical reflectors at different material distances from a transducer may be caused by:
    Material attenuation, beam divergence, and near field effects.
  10. When angle beam contact testing a test piece, increasing the incident
    angle until the second critical angle is reached results in:
    Production of a Surface Wave
  11. Acoustic energy propagates in different modes. The following represents
    a mode:
    Longitudinal wave, shear wave, and surface wave.
  12. 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
    Near Field
  13. The near field effects of a transducer in immersion testing may be
    eliminated by:
    using an appropriate water path
  14. What relationship would you expect to exist between the amplitudes of a
    reflected laminar signal if in position A, the transducer is right over the
    laminar reflector and in position B the transducer is clear of the laminar reflector?
    The amplitudes will be 2 to 1
  15. High sound loss was noted when testing course grain austenitic stainless steel, remedial action to improve this may be:
    use a lower frequency
  16. Optimum flaw detectability of lack of sidewall fusion is achieved when
    the beam is perpendicular to the fusion face
  17.                            (s-6)
    The Formula   A=-------- is use to calculate
  18. Which of the following flaws can be most accurately sized with the maximum amplitud technique
    Centreline crack
  19. Identify this indication DAC + 8dB signal drops of quickly when the probe swivelled plotted in base of weld length 26mm, Height 2mm, width 3mm
    lack of penetration
  20. What is generally accepted as the minimum thickness practically tested using manual scanning techniques
  21. The flaw detector shall be calibrated to EN12668 pt1 linearity of the time base shall be within _____ % in accodance with requirement
  22. The equal amplitude technique is generally only use to find
    laminations in the parent plate
  23. To which standard are terms and definitions of Ultrasonic addressed
    EN 1330
  24. Calibration of ultrasonic equipment shall be carried out in accordance with which of the following standards
    En 12668 Pt. 1 & 3
  25. At What angle is the transducers inclined with the perspex to produce a 38˚ refracted beam in steel 
    Perspex Velocity=2.760 x 1000000 mm/sec
    Steel Velocity    =3.23 x 1000000 mm/sec
    • sinß  38˚   .615        Vel1 2.760   .615x3.23=
    • --------  = ------- =   ----------- =        
    • sinß           Sinß        Vel2 3.23

    1.98/Vel2 3.23= .613 Sinß 38.8˚
  26. A 45˚ tranverse beam is desired when testing an aluminum plate by the inmersion technique. At what angle is it required to be inclined.

    Water velocity= 1.48 x 100000mm/sec
    Aluminium transverse velocity=3.08 x10(10)
  27. Beam spread/divergence occurs
    In the far field zone
  28. Which of the following combinations will give greater beam divergence.
    2 mhz 15mm diameter crystal
    4 mhz 5 mm diameter crystal
    2 mhz 20 mm diameter crystal
    4mhz 15 mm diameter crystal
    4 mhz 5mm diameter crystal
  29. which of the following defects types would be classified as diffuse
  30. which of the following would be classified as specular
    lack of fusion
  31. The use of too high current will give rise to which of the following faults
  32. The use of which shielding process is less likely to be disrupted by external draughty conditions
    gases formed by decomposition of fluxes during MMA
  33. which of the following techniques would require the least weld preparation
  34. which of the following techniques would best be use to weld thin aluminium plate
    tungsten inert gas
  35. which of the following weld flaws is caused by insufficient heat input
    lack of side wall fusion
  36. The cooling rate of a fusion weld is what in relation to that of a sand castinf
  37. Which of the following are gas shield weld process
    Metal inert gas - tungsten inert gas
  38. water cooled copper shoes are usually used in which of the following processes
    electro-slag welding
  39. Which welding process uses a non-consumable electrode
    tungsten inert gas
  40. soldering uses what type of material as a filler
  41. what type of defect is produced by gas entering the molten metal
    Gas pores ans worm holes
  42. In tig welding the nozzle around the electrode is generally made from
  43. which of the following would occur in the parent plate as a consequence of welding
    HAZ crack and lamellar tear
  44. In electric arc welding, a metal rod is one electrode, the other is
    the work material
  45. Stud welding is use primarily to
    attach threaded fasteners to plates
  46. a welding electrode coating provides
    a shield for the arc against the atmosphere
  47. Where gas is used as a shield for the welding process the gas is commonly
  48. when using gas metal arc welding, what range of filler wire diameter is commonly available
  49. Which of these defects can be found in fusion welds
    Porosity, slag, cracks
  50. That portion of the base metal affected by the welding process is known as
    the heat affected zone (HAZ)
  51. Multiple cooling rates can have adverse effects on weld areas, what can be done to offset this problem
    using preheat
  52. Angular distortion may occur in a weld when
    Single pass welds are use or muliptle pass welds
  53. longitudinal stresses in a weld area at a maximum
    along the weld centre line
  54. Automatic welding under a flux is more commonly known as
    summerged arc welding
  55. Spot welding is commonly use in which of the following applications
    car manufacturing
  56. Which welding process takes place in a vacuum
    electron beam welding
  57. which of the welding process is generally used to weld the ends of heavy round bars tubes
    friction welding
  58. which of the following techniques will best joint think steel plates in one run with the minimum amount of distortion
    electro-slag welding
  59. The drawing symbol illustrates a
    Fillet weld
  60. The drawing symbol illustrates a
    u groove weld
  61. Which of the following defects occur in the base metal
  62. which welding method gives a smooth surface weld with no discomfort from glare or fumes
    MIG Welding
  63. In TIG welding, the electrode is generally made from which materials
  64. What gas is use to shield the electrode when using MIG
  65. In the welding process, why would backing bars be employed
    to control root penetration
  66. Which of the following processes could give rise to slag inclusions
  67. The indication on the screen which represents the far boundary of the material being tested is called
    The back surface reflection
  68. 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 procedure is referred to as
  69. The cable that connects the ultrasonic instrument to the probe is called
    A coaxial cable
  70. The process of comparing a UT instrument with a standard is called
  71. Another name for a compressional wave is
    A longitudinal wave
  72. Another name for surface waves is
    Rayleigh wave
  73. A material use 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
    A couplant
  74. The piezoelectric material in a probe which vibrates to produce ultrasonic waves is called the
  75. Ultrasonic testing of material where the probe is in direct contact with the material being tested may be
    Straight beam, Surface wave and Angle beam testing
  76. An advantage of using lithium sulphate probes is that it
    is insoluble
  77. Which of the following probes would contain the thinnest quartz crystal
    1,5,15 and 25 mHZ
    a 25 Mhz search unit
  78. A 25 Mhz probe would most likely be used during
    Immersion testing
  79. The amount of beam divergence/Spread from a crystal is primarily dependent on the
    frequency and crystal size
  80. 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
  81. The velocity of the surface wave is approximately____ the velocity of shear waves in the same material
  82. Under normal circumstances, which of hte following frequencies would result in the best resolving power
    1mhz, 5mhz,10mhz,25 mhz
    25 mHz
  83. which of the following materials of the same alloy is most likely to produce the greatest amount of sound attenuation over a given distance
    a coarse grained casting
  84. In contact testing, the entry surface indication is sometimes referred to as
    BIP, Initial Pulse, Main bang
  85. A screen pattern containing a large number of low level indications often referred to as grass, could be caused by
    Coarse grain material
  86. A test method employing two separate probes on opposite surfaces of the material being tested is called
    through transmission testing
  87. The number of complete waves which pass a given point in a given period of time(usually 1s) is referred to as the
    frequency of wave motion
  88. The boundary between two different materials which are in contact with each other is called
    an interface
  89. When the motion of the particles of a medium is parallel to the direction of propagation, the wave being transmitted is called
    Longitudinal wave
  90. when the motion of the particles of a medium is at 90˚ to the direction of propagation, the wave being transmitted is called
    shear wave
  91. 25 million cycles per second can also be stated as
    25 mhz
  92. Moving a probe over a test surface either manually or automatically is referred to as
  93. A term used in ultrasonics to express the rate at which sound waves pass through various substances is
  94. An ultrasonic testing technique in which the transducer element is not parallel to the test surface is called
    angle beam testing
  95. Most commercial ultrasonic testing is accomplished using frequencies between
    0.2 mhz and 25 mhz
  96. I a A-scan presentation, the amplitude of signals on the screen represents the
    amount of ultrasonic sound energy returning to the search unit
  97. which of the following test frequencies would generally provide the best penetration in a 300 mm thick specimen of coarse grain steel
  98. In a basic ultrasonic test pattern (A-Scan) for contact testing(assuming no sweep delay is used) the initial pulse
    Is the high indication on the extreme left of the screen that represents the entry surface of the inspected part.
  99. an ultrasonic test using 0˚ probe is being conducted through the thickness of a flat part such as a plate, this test should detect
    Laminar type flaws with major dimensions parallel to the rolled surface
  100. In ultrasonic testing, a liquid coupling medium between the crystal surface and the part surface is necessary because
    an air interface between the crystal surface and the part surface would almost completely reflect the ultrasonic vibrations
  101. During ultrasonic testing by the immersion method, it is frequently necessary to angulate the search unit when a discontinuity is located in order to
    obtain a maximum response if the discontinuity is not originally oriented perpendicular to the ultrasonic beam
  102. Al other factors being equal, which of the following modes of vibration has the greatest velocity
    a longitudinal wave
  103. a piezoelectric material can
    Convert a mechanical strain to an electrical out put, convert an electrical pulse to a mechanical strain, be used in the construction of search units
  104. 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 frequency grater than approximately
    20,000 mhz
  105. The velocity of sound waves is mostly dependent upon
    the material, material thickness, and UT frequency (time between signals on the display
  106. Where does beam divergence occur
    In the far field zone
  107. As frequency decreases in ultrasonic testing, the angle of beam divergence of a given diameter crystal
  108. When examining materials for planar flaws oriented parallel to the part surface, what testing method is best used
    In straight beam testing
  109. Rayleigh waves are influenced most by defects located
    close to or on the surface
  110. finger damping is most effective locating a discontinuity when using
    compressional wave
  111. Lamb wave can be use to detect
    Laminar type defects near the surface of a thin material
  112. The ratio of the velocity of sound in water compared to that for steel is approximately
    1:4 ratio
  113. In an immersion test of a piece of steel or aluminium, the water distance appears on the display as a fairly wide space between the initial pulse and the front surface reflection because of
    reduce velocity of sound in water as compared test specimen
  114. Which law can calculate the angle of refraction within a material for both longitudinal and shear waves
    Snell's Law
  115. What will happen at an interface between two materials with differences in impedance values
    division of sound energy into transmitted and reflected modes
  116. during straight beam testing, test specimens with non parallel front and back surfaces can cause
    partial or total lost of back reflection
  117. On a A Scan display the dead zone refers to
    the distance covered by the front surface pulse width
  118. On a A scan display, what represents the intensity of a reflected sound energy
    signal amplituded
  119. which scan type can be used to produce a recording of a plan view of the test piece
    C Scan
  120. In immersion testing, a manually operated manipulator is used to
    set the proper water pulse, set the proper transducer angle
  121. In a straight beam contact testing, a reduction in the back surface reflection amplitude could indicate
    Inadequate coupling, A flaw which is not normal to the beam, a near surface defect that cannot be resolved from the main bang
  122. In an Automatic scanning immersion unit, the bridge or carriage serves to
    Support the manipulator and scanner tube and to move it about transversely and logitudinally
  123. When using a beam spread for a shear wave weld inspection, the zero point on the beam spread must coincide with the
    sound beam exit point of the wedge
  124. Which best describes a typical display of a crack whose major surface is perpendicular to the ultrasonic beam
    a sharp indication
  125. A primary purpose of a reference standard is
    to provide a guide for adjusting instrument controls to reveal discontinuities that are considered harmful to the end use of the product
  126. compensation for the variation in echo heights related to variations in discontinuity depth in the test material is known as
  127. where does the amplitude of an indication from a given discontinuity diminish exponentially as the distance increases
    Far field zone
  128. As the transducer diameter increases, the beam spread
  129. The angle at which 90˚ refraction of a longitudinal sound wave is reached is called
    the first critical angle
  130. Which of the following may affect attenuation values
    Beam spread, couplant mismatch, test piece geometry
  131. A large grain metallic material usually results in
    Decrease or loss of back surface reflection, high grass levels, decrease in penetration
  132. Total sound energy losses occurring in a material is called
  133. when the incident angle is chosen to be between the first and second critical angles, the ultrasonic wave generated within the part will be
    Shear wave
  134. The angle at which 90˚ refraction of the shear wave mode occurs is called the
    second critical angle
  135. For aluminium or steel the longitudinal velocity is approximately ___ the shear velocity
  136. A line of a number of crystals in one search unit vibrating in phase with each other to act as a single transducer is called a
    paint brush transduce
  137. The scattering of the sound beam due to reflections from a highly irregular surface is called
  138. The angle of reflection is equal to
    equal to the angle of incident
  139. A short burst of sound energy is called
    A pulse
  140. In ultrasonic testing, the time duration of the transmitted pulse is referred to as
    the pulse length
  141. the phenomenon by which a wave changes direction of propagation within the same material is referred to as
  142. which of the following wave modes gives the shortest wavelength at a given frequency in a given material
    surface wave
  143. In general which of the following modes of vibration would have the greatest penetrating power in a material if the frequencies are the same
    a longitudinal wave
  144. The distance from a given point on an ultrasonic wave to the next corresponding point is referred as
  145. The speed with which ultrasonic waves travel trough a material is known as
    velocity and sound energy
  146. The transducers most commonly found in ultrasonic search units(probes) used for discontinuity testing utilize
    Piezoelectric principles
  147. The formula sinø=sinø
                      ----   ----- is referred to as
                      v1      v2
    Snell's Law
  148.                   The formula
                      ----   -----   
                        v1      v2
    is use to determine
    Angular relationships
  149. The amount of energy reflected from a discontinuity will be dependent
    on size, orientation, and type of discontinuity
  150. Which of the following frequencies would probably result in the least ultrasonic attenuation losses  
    125 mhz, 10mhz,2.25mhz, 1.0 mhz
    1.0 Mhz
  151. The product of the sound velocity and the density of a material is known as the
    Acoustic impedance of the material
  152. The angle of reflection of an ultrasonic beam at an aluminium -water interface is
    equal to the angle of incidence
  153. what kind of waves travel at a velocity slightly less than shear waves
    Rayleigh waves
  154. which ultrasonic test frequency would probably provide the best penetration in a 200 mm thick specimen of coarse grained steel
    1 mhz
  155. Significant errors in ultrasonic thickness measured can occur if
    the velocity of propagation deviates substantially from an assumed constant value for a given material
  156. Generally, the best ultrasonic testing method for detecting discontinuities oriented along the fusion zone in a welded plate is
    an angle beam method using shear waves
  157. at water to steel interfaces the angle of incidence in water is 15˚ which of the following modes of vibration exists in the steel
  158. the only mode of vibration that can exist in a liquid is
    longitudinal waves
  159. The number of pulses produced by an instrument in a given period of time is know as the
    pulse repetition rate
  160. Most pulse echo ultrasonic instruments use
    An A Scan presentation
  161. A plan view of the part outline and defects will be shown when using
    a C- Scan presentation
  162. Incident angles where 90˚ refraction of longitudinal or shear waves occur are callerd
    the critical angles
  163. waves whose particles motion parallel to the direction of the propagation are called
    longitudinal waves
  164. the motion of particles in a shear wave is
    transverse to the direction of beam propagation
  165. The refraction angle of longitudinal ultrasonic waves passing from water into a metallic material at angles other than normal to the interface is primarily a function of
    the relative velocities of sound in water and metal
  166. as frequency increases in ultrasonic testing, the angle of beam divergence of a give diameter crystal
  167. In which medium would velocity of sound would be the lowest Air, water, aluminium, steel
  168. A longitudinal ultrasonic wave is transmitted from water into steel at an angle of 5˚ from the normal, In such case the refracted angle of the transverse wave is
    less than the refracted angle of the longitudinal wave
  169. the velocity of longitudinal waves will be the highest in  water, perspex, aluminium, steel