Ultrasonic Testing UT Level III Online Quiz

1) While testing a steel bar of 26 inch length, a reflection was received from a 0.5 inch FBH, located from the top surface at a distance of 4 inch at 40 dB amplifier setting, when the echo height was adjusted to 40% of screen height. If in a second test run for the same material, an echo was registered for an amplifier setting of 28 dB for the same FBH and for the same 40% screen height. What could be the distance between the FBH and the top surface in the latter case? Assume the material has 0.0 dB/inch attenuation co-efficient.

2) An inspection specification calls for three hits of an echo in order for the flaw to be considered valid and for the alarm to sound. The maximum axial speed of test part movement is therefore ___ for a 1 inch dia transducer (assume no beam spread) and a PRR of 600 pulses per second.

3) What does the term "resonant frequency" refer to in the context of resonance testing?

4) What shapes can notches be made in ultrasonic testing?

5) If Cw = velocity in water and Cp = velocity in perspex, at perspex/water interface, a con A convex lens made in perspex will act as a:

6) What is the primary focus of MIL-STD-2154?

7) What is the primary function of the pulser in pulsed ultrasonic testing?

8) What is the original examination method that used lip-diffraction?

9) While testing a steel plate of 6 inch thick, a reflection was received from a 0.5 inch FBH, located from the top surface at a distance of 4 inch at 40 dB amplifier setting, when the echo height was adjusted to 40% of screen height. In an actual test for the same material an echo was registered at the same depth and amplitude for an amplifier setting of 52 dB. What could be the equivalent defect size of the reflector?

10) What is the purpose of the backing material in the UT transducer?

11) Analysis of the frequency content of signals returned from flaws is called

12) What happens to the reflected sound energy from a flaw smaller than the wavelength?

13) Why might a scanning surface need to be sanded or ground before ultrasonic testing?

14) To correct the effects of magnetic arc blow in metal arc welding you could

15) What is a common method to remove bubbles from the transducer face?

16) A specification calls for shear wave angle beam examination. What angle should be used?

17) What is an advantage of side-drilled hole reflectors for calibration?

18) The purpose of the axicon lens in use with an ultrasonic transducer is to

19) Using a transducer with a focal length of 10 inches in water to focus the beam to a point 0.4 inches below the surface of a cast iron part, the water path distance will be (velocity in water : 1.5x105 cm/sec and in cast iron: 3 x 105 cm/sec):

20) A change of 16 dB on the attenuator corresponds to an amplitude ratio of:

21) A 4.00 MHz straight beam transducer (24mm dia) is employed to test an 8" diameter x 1.0" thick pipe rotating inside a tank at 120 RPM to detect transverse flaws. Water path is 60 mm. Calculate the minimum PRR required.

22) Longitudinal ultrasound wave travels from steel into water at an angle, the refracted longitudinal beam in water will be bent:

23) What is a significant advantage of the pulse-echo technique?

24) When a probe is placed on a convex surface divergence can decrease the near field unpredictably. For this reason

25) How is the search unit mounted in a wheel transducer?

26) The reflected pulse reaching the immersion transducer from the back surface of a 6.5" titanium alloy standing in a tank of water is equal to ___ of the energy pulse which was transmitted from the transducer (velocity in water : 1.5x105 cm/sec and in cast iron: 3 x 105 cm/sec).

27) What is a limitation of using sacrificial samples with embedded reflectors for UT testing?

28) In critical-angle analysis the signal studies is the

29) In contact testing, the back surface signal from a 3 inch plate was set at full screen height. Passing over a coarse grained area, the back surface signal dropped to 20% of the full scale signal. What would be your estimate of the change in attenuation in this local area?

30) How does Huygens' principle describe the transducer face?

31) What is the role of the reject function in the UT equipment system?

32) To avoid the second front reflection from the test piece appearing before the back surface reflection of the 5 inches thick Perspex test piece, the minimum water path in immersion testing should be (velocity in water : 1.5x105 cm/sec and in perspex: 2.7 x 105 cm/sec):

33) At a liquid/solid boundary with an obliquely incident shear wave from the solid, the result could be at most

34) While testing a steel bar of 8 inch thick, a reflection was received from a 0.5 inch FBH, located from the top surface at a distance of 2 inch at 40 dB amplifier setting, when the echo height was adjusted to 50% of screen height. In an actual test on the similar material an echo was registered at the depth of 6 at 54 dB for the same screen height. What is the equivalent defect size of the indication? Assume the material has 0.0 dB/inch attenuation co-efficient.

35) How long must suppliers retain records of ultrasonic inspections?