NDT Nondestructive Testing Methods & Techniques 2

Question 1

Which NDT method is most effective for detecting surface-breaking cracks in ferromagnetic boiler components?

Accepted Answer

Magnetic particle testing

Answer

Liquid penetrant testing

Answer

Radiographic testing

Answer

Ultrasonic testing

Question 2

In radiographic testing, what does a darker area on the developed film typically indicate?

Accepted Answer

A less dense region such as a void or porosity

Answer

A denser region with fewer voids

Answer

A thicker section of base metal

Answer

A area with higher alloy content

Question 3

What is the primary purpose of a calibration block in ultrasonic testing?

Accepted Answer

To establish reference amplitude levels and distance measurements

Answer

To measure the thickness of the couplant layer

Answer

To determine the chemical composition of the material

Answer

To verify the power supply voltage of the UT instrument

Question 4

A boilermaker performing liquid penetrant testing discovers bleed-out that appears as a broad, fuzzy indication. This most likely suggests:

Accepted Answer

A wide, shallow surface discontinuity or porosity cluster

Answer

A tight, surface-breaking crack

Answer

A subsurface lamination

Answer

Correct penetrant dwell time was not achieved

Question 5

When performing magnetic particle testing using the wet fluorescent method, inspection must be conducted under:

Accepted Answer

Ultraviolet (black) light with ambient white light below 2 foot-candles

Answer

Normal white light conditions above 100 foot-candles

Answer

Infrared light at wavelengths above 700 nm

Answer

Daylight only to avoid UV exposure hazards

Question 6

In ultrasonic shear wave (angle beam) testing of a weld, the probe is typically positioned on the:

Accepted Answer

Base metal adjacent to the weld

Answer

Weld crown directly

Answer

Back surface of the plate

Answer

Weld root only

Question 7

Which of the following is a limitation of visual testing (VT) as an NDT method?

Accepted Answer

It can only detect discontinuities open to the surface that are visible to the eye

Answer

It cannot detect surface conditions on the material

Answer

It requires expensive and complex equipment

Answer

It is only applicable to non-metallic materials