Top 1000+ Solved Non Destructive Testing and Evaluation MCQ Questions Answer
Q. Magnetic particle testing is most likely to find subsurface discontinuities in:
a. Soft steels with high permeability
b. Soft steels with low permeability
c. Hardened steels with low permeability
d. Hardened steels with high permeability
Q. Which of the following is not an advantage of Magnetic Particle testing?
a. Fast and simple to perform
b. Can detect discontinuities filled with foreign material
c. Most reliable for finding surface cracks in all types of material
d. Works well through a thin coat of paint
Q. The most effective NDT method for locating surface cracks in ferromagnetic materials is:
a. Ultrasonic testing
b. Radiographic testing
c. Magnetic particles testing
d. Liquid penetrant testing
Q. Opposition to establishment of a magnetic field in a test piece is called:
a. Reluctance
b. Retentivity
c. Permeability
d. Electromagnetism
Q. A leakage field is strongest when a discontinuity interrupts the magnetic flux lines atan angle of:
a. 0o
b. 45o
c. 90o
d. 180o
Q. A common rule of thumb to use for current required in circular magnetisation:
a. 1000 amps/25 mm of diameter
b. 1000 ampere-turns/25 mm of diameter
c. 1000 amps/25 mm of prod spacing
d. None of the above
Q. The formula, NI = 45000/(L/D), is used to calculate the proper magnetising currentfor:
a. Prod magnetisation
b. A head shot
c. A central conductor
d. Coil magnetization
Q. For direct contact magnetising methods, the magnetic field is oriented in whatdirection relative to the current direction?
a. Parallel
b. At 45o
c. At 90o
d. At 180o
Q. For direct contact magnetising methods, current should be flowing in what directionrelative to expected discontinuities?
a. Parallel
b. At 45o
c. At 90o
d. At 180o
Q. What is the magnetic field strength at the surface of a 25 mm diameter bar as comparedto that at the surface of a 50 mm diameter bar, each carrying 1000 amps of current?
a. Twice
b. One half
c. One quarter
d. Four times
Q. Demagnetization, ASTM E709-95 recommends a coil of ampere-turns:
a. 1000 to 3000
b. 3000 to 5000
c. 5000 to 10000
d. 10000 to 15000
Q. According to ASTM E709-95 in using prod technique, prod spacing shall not exceed:
a. 50 mm
b. 100 mm
c. 150 mm
d. 200 mm
Q. According to ASTM E709-95, the UV intensity shall not be less than:
a. 600 µW/cm2
b. 700 µW/cm2
c. 800 µW/cm2
d. 900 µW/cm2
Q. According to ASTM E709-95 in using prod technique on a 50 mm thickness plate witha prod spacing of 101 mm (4 inches), current shall be selected in the following range:
a. 300-450A
b. 400-500 A
c. 500-625A
d. 550-700 A