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: 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