Glossary

Terms relating to casting and machining.

ADI (Austempered Ductile Iron)

  • The excellent properties of ADI are achieved by heat treating alloyed ductile iron according a special heat treatment program.

Automatic moulding

  • A moulding system controlled by machine. An automatic moulding line operates without the intervention of the operator apart from when problems occur.

CAD

  • Computer Aided Design.

CAM

  • Computer Aided Manufacturing.

Carburizing

  • The process by which the surface carbon concentration of ferrous alloy is increased by diffusion from the surrounding environment. Adding surface hardness.

Cast iron

  • Ferrous metal that contains 2.0 – 4.2% carbon. The carbon is usually in the form of graphite. Ferrous metals are divided into grey cast iron (GJL), nodular cast iron (GJS) and white cast irons.

Charge

  • Mix or pig iron, recycled steel, return, chips and ferro-alloys to make the composition for cast iron in the melting furnace.

Chip

  • Metal chips, machining waste material.

CNC machine

  • Computer Numerical Controlled machine

Coating

  • Coating of the sand cores and moulds made from furan sand to obtain sufficiently high surface quality and to prevent the metal penetrating the sand.

Core

  • Sand part which forms interior shapes of the casting (cold-box and shell-core).

Core box

  • Box for sand cores production, in which the internal elements give the form of the core.

Dimensional accuracy

  • Quality parameter which describes the accuracy of the dimensions of a part compared to the drawing or CAD file.

Finishing, trimming

  • After casting the remaining runners and feeders are removed by fettling.

Grey cast iron

  • Grey iron, GJL, a cast iron in which the graphite exists in the form of flakes. The fractured surface appears grey.

Hardening

  • Heat treatment method to increase the hardness of the metal.

Heat treatment

  • Heat treatment aims at converting material properties. It consists of heating and usually controlled cooling.

Holding furnace

  • Electric furnace for holding molten metal. Typical size 30 tonnes.

Lathe

  • Chipping machine tool (for rotating symmetrical materials).

Machining

  • General name for various machine tool methods, such as drilling, milling, lathing and grinding.

Machining allowance, Tooling allowance, Allowance

  • Additional material in castings for machining purposes. In castings machining allowance is usually 2-5 mm.

Machining centre

  • Machine with several machine tool options, for example drilling, milling, lathing and grinding. Cutting fluid (normally water-based) is used in machining to prevent the tool from getting hot from the friction.

Melting furnace

  • The furnace in which melting takes place. Source of energy is electricity (= electric furnace) or coke (= cupola furnace). In the electric furnace melting takes place in a single charge, meaning that the furnace is emptied completely or partially once a batch is ready. For example, it takes about one hour 20 minutes to melt 8 tonnes at a power of 4.3 MWh. The cupola furnace process is continuous, so molten metal is taken out and raw material added in a continuous process.

Metallurgy

  • Branch of science and technology concerning metals.

Mould

  • Mould formed from moulding sand for casting a product. The mould contains a hollow area that is the shape of the product, the runners needed to direct the molten metal and feeders to compensate for the shrinking of the molten metal.

Moulding

  • Stage, where by means of a casting pattern, a mould is formed into the moulding sand. A half of the cast pattern is placed in the moulding box and around it will be stacked the moulding sand, by hand (hand moulding) or by machine (automatic moulding). The cores for making hollow interiors inside the castings are also placed in the moulds in the moulding stage.

Nodular cast iron

  • GJS, cast iron which contains 3.0 - 3.9% carbon and in which the free graphite exists in nodular form, also called ductile iron.

Particle emissions

  • Emissions may cause for example dirtying and discomfort.

Pattern

  • Form of wood, metal or plastic, around which moulding material is placed to form a mould.

Pressure die casting

  • Molten metal is led into a metallic die (mould) at high pressure and speed. HPDC means high pressure die casting.

Primer and powder coating

  • Priming/finishing. Protects material from corrosion and improves surface appearance.

Produced ton

  • Produced tonnes after deducting rejects..

Recycled metal

  • Left-over raw material from the manufacturing process, such as plate cutting waste, and end-of-life iron, aluminium, and steel products.

Remelting

  • Melting material that has already once  been molten material, for example burrs, scrapped pieces or machining waste materials.

Runners and feeders

  • The runners and feeders full of molten metal that are removed when cleaning the cast item. These can account for anything from 15% to 50% of the total iron, depending on the product, grade of iron and casting system.

Roughing

  • Machining phase where material is chipped as effectively as possible without aiming at high accuracy or surface quality.

Sand core

  • A core made of sand and core binder used for making hollow interior parts and complex shapes for castings. The sand cores are removed by breaking.

Shot blasting

  • Small metallic balls or particles are shot at high speed onto the surface of the casting to remove remains from sand and coating. 

Squeeze casting

  • Casting method for high quality castings produced by a high pressure technique. Castings are heat-treated.

SSF Ductile iron

  • Silicon Solution Strengthened Ferritic Ductile iron possess higher yield strength and elongation than ferritic to pearlitic ductile irons.

Surface treatment

  • Method which aims to improve the surface quality of materials for example TiN-coating (wear-resistant).

Ultrasonic testing

  • A non-destructive method of testing in which the casting is checked by ultrasound for internal soundness.

VOC

  • Volatile organic compounds. VOC emissions form ozone in the lower atmosphere when they react in the presence of sunlight with nitrogen oxide. Ozone in the lower atmosphere is harmful to plants and to the health of human beings. Nitrogen oxide is formed for example by traffic emissions.