WCL Inspection & Quality Control 3

Question 1

What is the minimum preheat temperature requirement primarily intended to prevent?

Accepted Answer

Hydrogen-induced cracking

Answer

Preheat is primarily used to slow the cooling rate and allow hydrogen to diffuse out of the weld, preventing hydrogen-induced (cold) cracking.

Question 2

During visual inspection of a completed weld, a CWI finds a crack. What is the appropriate action?

Accepted Answer

Mark and reject the weld for repair

Answer

Cracks are rejectable under all major welding codes; the CWI must mark and reject the weld so it can be repaired per an approved repair procedure.

Question 3

What does the term 'heat-affected zone' (HAZ) refer to?

Accepted Answer

Base metal area altered by welding heat but not melted

Answer

The HAZ is the portion of the base metal that has not melted but whose microstructure and properties have been altered by the heat of welding.

Question 4

A CWI using magnetic particle testing on a carbon steel weld would NOT be able to detect:

Accepted Answer

Internal porosity 1 inch below the surface

Answer

Magnetic particle testing is effective only for surface and near-surface (typically within 1/4 inch) discontinuities and cannot reliably detect defects deep within the material.

Question 5

What is the purpose of a nick-break test in weld inspection?

Accepted Answer

To expose the internal cross-section for visual examination

Answer

A nick-break test fractures a weld sample to expose the internal cross-section, allowing visual examination for porosity, slag inclusions, and incomplete fusion.

(WCL) Welding Certification Los Angeles Practice Test

(WCL) Welding Certification Los Angeles Practice Test

WCL Inspection & Quality Control 3