Why Controlling Sand Compactability Is Critical to Quality

As highlighted by THORS in their article “How to Control Compactability of Sand?”, compactability is a vital characteristic in green sand casting, directly impacting the quality of molds and final castings. Defined as the sand’s reduction in volume after compression, compactability determines how well sand fills pattern pockets, retains mold integrity at edges and corners, and maintains consistent density.

Ideal compactability should fall within the range of 36 to 42. Achieving and maintaining this range depends largely on one key factor: moisture control. During the mulling process, water is added to a mix of clay and sand. This water is absorbed by clay platelets, which swell and allow the sand to become more compactable. However, as mulling continues, the absorbed water increases, and compactability begins to decline. Therefore, compactability must be precisely controlled in the muller to meet molding machine specifications—typically 4 to 15 points higher than the final requirement.

Click here to learn more about Plymouth Foundry’s sand casting capabilities or here to read the full article.

Article with all rights reserved, courtesy of THORS — https://thors.com

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