Characteristics and remedy of air pocket defects in sand casting

Defect characteristics and detection methods

The smooth and glossy dimples and pits on the surface of castings where chill is placed.

Causes of formation
  1. Interaction between water condensed on cold iron and alloy liquid
  2. The part of sand mold and core is not dried or re hygroscopic
  3. The mandrel placed is not treated or placed incorrectly
Prevention methods and remedial measures
  1. Design and place the cold iron accurately, and dry it before placing
  2. Thoroughly dry sand mold and core
  3. The aluminum alloy mandrel shall be designed and placed according to the shape and structure of the cylindrical part of the casting, and dried before placement
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