CRI Welding Defects Identification 2 — Questions and Answers
Question 1: On a radiograph, a planar defect oriented parallel to the X-ray beam will appear:
- As a sharp, well-defined dark line (Correct answer)
- As a diffuse, light area
- Completely invisible
- As a rounded dark spot
Correct answer: As a sharp, well-defined dark line
Planar defects such as cracks aligned parallel to the beam show maximum density contrast and appear as sharp dark lines.
Question 2: Incomplete fusion in a radiograph is most likely to appear as:
- A rounded, smooth-edged dark indication
- A straight or slightly curved dark line along the weld fusion line (Correct answer)
- Random scatter of dark spots
- A light, irregularly shaped area
Correct answer: A straight or slightly curved dark line along the weld fusion line
Incomplete fusion appears as a dark line located at the weld fusion zone because the unbonded interface creates a density-rich gap.
Question 3: Which welding defect produces a radiographic image with a light (less dense) region surrounded by darker areas?
- Porosity
- Tungsten inclusion (Correct answer)
- Crack
- Undercut
Correct answer: Tungsten inclusion
Tungsten inclusions appear lighter (less radiographically dense) than the surrounding weld metal because tungsten has a higher atomic number and absorbs more radiation.
Question 4: A radiograph shows a series of elongated dark indications with irregular edges running longitudinally in the weld. This pattern is most consistent with:
- Scattered porosity
- Wormhole (piping) porosity (Correct answer)
- Tungsten inclusions
- Incomplete joint penetration
Correct answer: Wormhole (piping) porosity
Wormhole or piping porosity creates elongated, tunnel-like voids that appear as irregular dark elongated indications oriented along the weld axis.
Question 5: What radiographic characteristic distinguishes undercut from a crack at the weld toe?
- Undercut appears as a lighter area; cracks appear darker
- Undercut is located outside the weld metal; cracks can be anywhere
- Undercut has a smoother, more uniform edge compared to a crack (Correct answer)
- Undercut only appears on the root side of the weld
Correct answer: Undercut has a smoother, more uniform edge compared to a crack
Undercut typically shows a smoother, more continuous dark line at the weld edge, while cracks display irregular, branching edges.
Question 6: In radiographic testing, the term 'geometric unsharpness' affects the ability to detect:
- Large volumetric defects near the center of the weld
- Small planar defects whose images become blurred (Correct answer)
- Tungsten inclusions regardless of their size
- Surface-breaking defects only
Correct answer: Small planar defects whose images become blurred
Geometric unsharpness blurs the edges of defect images, making small or fine planar defects difficult to detect and characterize.
Question 7: A radiographic indication showing a very dark, narrow line with branching extensions is most indicative of:
- Cluster porosity
- Longitudinal crack (Correct answer)
- Slag inclusion
- Cold lap
Correct answer: Longitudinal crack
Longitudinal cracks appear as dark, narrow lines that may branch or taper, reflecting the planar, tight nature of the discontinuity.
CRI Welding Defects Identification 2
On a radiograph, a planar defect oriented parallel to the X-ray beam will appear: