How to Solve the Common Casting Defects?

Raymond Machinery Co.,Ltd has been a supplier of casting parts for more than 15 years. When customers want to make a part by casting process, the first should be considered is how to solve casting defects. Following is listing of common casting defect, and the solutions.

Shrinkage Cavity and Porosity:

• Causes: This occurs due to inadequate feeding of the molten metal during the solidification process.
• Solutions:Design the gating and risering system properly to ensure sufficient feeding of the molten metal. For instance, place large risers in thick sections of the casting.

Optimize the casting structure to make the wall thickness uniform and reduce hot spots.

Gas Holes:

• Causes: Gases in the mold cavity fail to escape during the solidification of the molten metal.
• Solutions:Enhance the permeability of the mold, such as using molding sand with good permeability.

Control the melting process to reduce the gas content in the molten metal.

Inclusions:

• Causes: Impurities like slag or molding sand from the mold get mixed into the molten metal.
• Solutions:Strengthen the refining of the molten metal to remove the slag.

Ensure the quality of the molding sand to prevent its incorporation into the molten metal.

Cracks:

• Causes: Uneven cooling of the casting results in excessive internal stress.
• Solutions:Optimize the casting process parameters.

Use appropriate heat treatment methods to relieve the internal stress.

Misrun:

• Causes: Insufficient fluidity of the molten metal or improper gating system.
• Solutions:Select suitable alloys with better fluidity.

Improve the gating system to ensure smooth filling of the mold cavity.

Cold Shut:

• Causes: Interrupted flow of the molten metal during pouring.
• Solutions:Increase the pouring temperature and speed.

Improve the pouring system to avoid metal flow interruption.