Glossary of Terms

The following Glossary of Terms is intended to be a quick reference guide of terms commonly used in the metal casting industry.


ACCURACY: Control to drawing


AIRSET MOULD: Using a process of chemically bonded sand hardening over a period of time by the reaction between a resin and hardener


ALOCROM: Protective surface treatment usually as a precursor to painting


ANODISE: Surface treatment to protect against corrosion


BRASS: Alloy of copper and zinc


BRONZE: Alloy of predominately copper, zinc, tin and lead


CAST: To fill a mould with molten metal


CAST IRON: Iron that has been melted and poured to shape


CERTIFICATE OF ANALYSIS: A certificate stating the chemical analysis of the metal in the casting


CERTIFICATE OF CONFORMITY: A certificate stating that the material in the casting conforms to the specification of the drawing


COINS: A sample of the same metal, in the shape of a coin, which is used to produce the casting which is tested in a laboratory to determine the physical properties of the material


CONTRACTION: Loss in dimensions when cooling from the liquid to solid, and then to room temperature


COPE: The top part of a 2-part sand casting mould (the DRAG is the bottom part)


CORE: Sand shapes to assemble into a mould to create internal shapes and some external shapes


COREBOX: Tooling required to form internal & some external shapes


COREMAKER: Operator producing cores


CO2 PROCESS: Chemical hardening process where the silica sand is mixed with sodium silicate until all the grains are coated. The mould or core is then made with this and carbon dioxide is then passed through the sand which sets the sodium silicate, thus hardening the mould or core


DE-CORE: Removing the sand forming the internal shape for the casting


DE-GAS: Remove gas bubbles taken into the solution by the molten metal


DISAMATIC CASTING: A technique for producing long lengths of cast product, whereby the molten metal is poured into a funnel on top of a sand casted mould, then when it is set, the mould opens up to allow the product to be pushed out.


DRAG: The top part of a 2-part sand casting mould (the COPE is the top part)


DRAWING: Detailed two dimensional views of a component


DROSS: Impurities in non-ferrous metals


ESTERSET PROCESS: A process of self-hardening sand using chemicals of the ester family of very low toxicity


FEEDER: Device providing extra molten metal to the cavity as it solidifies


FERROUS: Alloy of iron


FETTLE: Removing all runners & feeders from the casting & de-burring


FINISH: Surface, texture or coating


FIRST: Initial article produced as a test piece to check tooling


FIXED CRUCIBLE TILTING FURNACES: A furnace which has a fixed crucible and is emptied by tilting its axis and decanting the molten metal into a ladle for pouring


FURNACE: Vessel for melting and treating metals & alloys


FURNACEMAN: Operator who melts & treats metal in a furnace


GREENSAND PROCESS: A process using natural quarried sand which does not contain hardening chemicals but relies on its natural green strength when compacted into the mould


GRIND: Removing excess by means of an abrasive stone or wheel disc


GUNMETAL: Member of the bronze family


HEAT: Term given to an individual melt of metal


HEATTREAT: Process of stress relief, hardening and development of tensile strength carried out in an oven or furnace


KNOCKOUT: Breaking up the mould & removing the casting


LACQUER: Protective coating against corrosion


LIFT OUT CRUCIBLE FURNACES: A furnace which has a free standing crucible within it which, when the metal has melted, is lifted out and into a carrying shank for pouring


LINISH: Removing excess with an abrasive belt


LOW GAS EVOLUTION SELF SETTING PROCESS: A process using chemicals specially designed to produce very low levels of gas evolution when surrounded by molten metal


MACHINE: To achieve dimensions by accurately removing metal in a lathe or similar




MODIFY: Refine the grain structure of molten metal in the furnace


MOULD: The form into which molten metal is poured to produce a casting


MOULDER: Operator producing moulds


NODULAR: Graphite in spheres or modular shape


NON FERROUS: Does not contain iron


OXIDE: Skin formed on non-ferrous metals when molten


PAINTING: Wet paint or powder coating given to the casting surface


PATTERN: Tooling required to make a mould


PATTERNMAKER’S SHRINKAGE: The allowance added to the component geometry to allow for shrinkage of the alloy as it cools.


PLATING: A metallic coating given to the casting surface


POUR: To cast a mould


PRESSURETIGHT: Will not leak under pressure.


RUNNER: Device in the mould to convey molten metal from the sprue to the mould cavity or on to additional moulds where several moulds are joined.


SAMPLE: Example of first production


SANDBLAST: Cleaning a casting by impaction of sand on the surface


SHOT: Fine metal bearings


SHOTBLAST: Cleaning a casting by impaction of steel shot on the surface


SLAG: Impurities in ferrous metals


SOLIDIFICATION: Transformation from the liquid state to the solid state


SPHEROIDAL: Graphite in spheres or modular shape


SPRUE: The passage through which a molten material is introduced into a mould and the term also refers to the excess material which solidifies in the sprue passage.


SURFACE FINISH: The texture or appearance of the casting skin or the coating which is given to it such as paint or plating


TEST BARS: A sample of the same metal which is used to produce the casting which is tested in a laboratory to determine the physical properties of the material


TOLERANCE: The range permissible on a given dimension e.g. + or – .006


TOOLING: Generic term for the moulds, casts and runners required to successfully make an item


TREATMENT: Secondary & tertiary processes to a casting