What are the types of welding defects?

What are the types of welding defects?

We can break down weld defects into the following main categories;

  • Inclusions.
  • Lack of fusion.
  • Porosity.
  • Undercut.
  • Under-fill.
  • Cracks.
  • Excess reinforcement and excess penetration.
  • Over-roll/Overlap.

Which defect in welding is called external defect?

External welding defects are found on the surface itself and can sometimes be recognized by naked eyes. Surface Cracks, Undercut, Porosity, Overlaps, Crater, Underfill, Spatters, Excessive penetration, Arc Strike, etc are examples of external welding defects.

What is external defect?

External defects are defects which can be detected externally. However, cutting may be required to determine the extent of the injury.

What causes porosity?

Porosity is caused by the absorption of nitrogen, oxygen and hydrogen in the molten weld pool which is then released on solidification to become trapped in the weld metal. Nitrogen and oxygen absorption in the weld pool usually originates from poor gas shielding.

What are weld discontinuities?

Weld discontinuities can be defined as “an interruption of the typical structure of a weld, such as a lack of homogeneity in the mechanical, metallurgical or physical characteristics of the weld.” Weld discontinuities include porosity, slag inclusions, incomplete fusion, incomplete joint penetration, excessive melt- …

What is internal defect?

internal defect means any instance where a Statement Package, Transaction Card Package, Statement, Letter, or Other Correspondence contains one or more observed Defects, which Defect is discovered prior to the Statement Package, Transaction Card Package, Statement, Letter, or Other Correspondence being Released into …

What is an example of an external defect?

External defects have many different origins, including fungal attack, insect or bird bites, various mechanical wounds, and physiological factors such as frost damage and sunburn.

What is surface porosity in welding?

Porosity is the presence of cavities in the weld metal caused by the freezing in of gas released from the weld pool as it solidifies. The porosity can take several forms: distributed. surface breaking pores.