Casting defect

The defects in a casting may be due to pattern and moulding box equipment, moulding sand, cores,gating system or molten metal. Some of the defects are:

1: Mould shift

It results in a mismatching of the top and the bottom parts of the casting , usually at the parting line.

2: Swell

It is an enlargement of the mould cavity by molten metal pressure resulting in localized or general enlargement of the casting.

3: Fins and Flash

These are thin projections of the metal not intended as a part of casting. These usually occurs at the parting line of the mould.

4: Sand Wash

It usually occurs near the in the gates as rough lumps on the surface of a casting.

5: Shrinkage

It is a crack or breakage in the casting on the surface of the work piece, which results from unequal contraction of the metal during solidification.

6: Hot Tear

It is an internal or external ragged discontinuously in the metal casting resulting just after the metal has solidified.

7: Sand Blow or Blow Hole

It is smooth depression on the outer surface of the casting work piece.

8: Honeycombing or Slag holes

These are smooth depression on the upper surface of the casting. They usually occur near the ingates.

9: Scabs

These are patches of sand on the upper surface of the casting component.

10: Cold Shut and Misruns

These happens when the mould cavity is not completely filled by the molten and insufficient material or metal.

11: Run-outs and Bust-outs

These permit drainage of the metal from the cavity and result in incomplete casting.