Question
Download Solution PDFA balloon-shaped gas cavity caused by the release of mold gases during pouring is called ________.
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFEXPLANATION:-
Sand blow:
- This defect consists of a balloon-shaped gas cavity caused by the release of mold gases during pouring.
- It occurs at or below the casting surface near the top of the casting.
- Low permeability, poor venting, and high moisture content of the sand mold are the usual causes.
Pin holes:
A defect similar to a sand blow involves the formation of many small gas cavities at or slightly below the surface of the casting.
Sand wash:
- A sand-wash is an irregularity in the surface of the casting that results from erosion of the sand mold during pouring.
- The contour of the erosion is imprinted into the surface of the final cast part.
Misrun:
A misrun is a casting that has solidified before completely filling the mold cavity.
Typical causes include
- The fluidity of the molten metal is insufficient,
- The pouring temperature is too low,
- Pouring is done too slowly, and
- The cross-section of the mold cavity is too thin.
Last updated on May 12, 2025
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