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
MALLEABLE: Ductile
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:Â 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