What casting discontinuity results from splashing or interrupted pouring, or meeting of two streams?

• A. A cold shut
• B. Flaking
• C. A burst
• D. A blow hole

Answer: (A)

The key idea is a defect that forms when two streams of molten metal enter the mold and do not fuse together before solidification. When pouring is splashed or interrupted, the flow can split into separate fronts that meet in the cavity but fail to weld into a single, continuous mass. As the metal cools, a seam or thin fissure remains along the line where the fronts touched, creating a cold shut. This type of discontinuity is often seen in areas where flow meets or in corners with restricted mold filling, and it weakens the casting along that plane. Other defects describe different causes—gas porosity or blow holes from trapped gas, flaking from surface separation, or other rupture phenomena—not the fusion of two separate streams—so they don’t fit the scenario described.