Pipe Defect: A discontinuity in the centre of the ingot, caused by cavities formed during solidification Becomes elongated in rolling operations Not usually visible on the surface of the article.
2nd stage of discontinuity
Generated by forming or fabrication operations subdivided into: primary processing discontinuities: Casting, rolling, forging.
Secondary processing discontinuities – Machining, grinding, heat treating, welding, plating.
Primary Processing Discontinuities – Casting
- Cold shuts
- Hot tears
- Shrinkage cavities