Casting Defects
10:15 AM
, Posted in
Casting Defects:
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 un equal 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.
