Which of the following is a common defect in welded joints?

• A. Porosity
• B. Cracking
• C. Overlapping
• D. All of the above

Answer: (D)

In welded joints, various defects can arise due to the welding process, and it's crucial to identify these potential faults to ensure the integrity and quality of the weld. A common defect that can occur is porosity, which involves small cavities or holes formed within the weld caused by trapped gas. This can weaken the weld and lead to failure under stress.

Cracking is another significant defect that can occur as a result of rapid cooling or improper welding techniques. It can manifest in different forms, such as hot cracking, which occurs while the weld is still hot, or cold cracking, which appears after the welding is completed. Cracks can severely diminish the strength and reliability of the joint.

Overlapping is also a recognized defect in welded seams, which happens when the weld metal fails to fuse properly to the base metal, creating a lip on the joint instead of a smooth, continuous bond. This defect typically arises from incorrect technique or insufficient heat.

Given that all these defects—porosity, cracking, and overlapping—are considered common issues that can affect the quality of welded joints, it stands to reason that identifying all of them is crucial for ensuring robust and reliable welds. Thus, selecting the option that encompasses all these defects is justified, as each one can lead