Semi-finished casting products are intermediate

casting Casting is a manufacturing process in which a liquid material is usually poured into a mold, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a casting, which is ejected or ...

s produced in a steel mill that need further processing before being finished goods. There are four types: ''ingots'', ''blooms'', ''billets'', and ''slabs''.

Ingot

Ingots are large rough castings designed for storage and transportation. The shape usually resembles a rectangle or square with generous fillets. They are tapered, usually with the big-end-down.

Bloom

In the era of commercial wrought iron, blooms were slag-riddled

iron Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...

castings poured in a

bloomery A bloomery is a type of metallurgical furnace once used widely for smelting iron from its iron oxides, oxides. The bloomery was the earliest form of smelter capable of smelting iron. Bloomeries produce a porous mass of iron and slag called ...

before being worked into wrought iron. In the era of commercial

steel Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...

, blooms are intermediate-stage pieces of steel produced by a first pass of

rolling Rolling is a Motion (physics)#Types of motion, type of motion that combines rotation (commonly, of an Axial symmetry, axially symmetric object) and Translation (geometry), translation of that object with respect to a surface (either one or the ot ...

(in a blooming mill) that works the ingots down to a smaller cross-sectional area, but still greater than . Blooms are usually further processed via rotary piercing, structural shape rolling and profile rolling. Common final products include structural shapes, rails, rods, and seamless pipes.

Billet

A billet is a length of metal that has a round or square cross-section, with an area less than . Billets are created directly via continuous casting or extrusion or indirectly via hot rolling an ingot or bloom. Billets are further processed via profile rolling and

drawing Drawing is a Visual arts, visual art that uses an instrument to mark paper or another two-dimensional surface, or a digital representation of such. Traditionally, the instruments used to make a drawing include pencils, crayons, and ink pens, some ...

. Final products include bar stock and

wire file:Sample cross-section of high tension power (pylon) line.jpg, Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample d ...

. Centrifugal casting is also used to produce short circular tubes as billets, usually to achieve a precise metallurgical structure. They are commonly used as cylinder sleeves where the inner and outer diameters are ground and machined to length. Because their size is not modified significantly, they are not always classified as semi-finished casting products.

Slab

A slab is a length of metal that is rectangular in cross-section. The slab is created directly by continuous casting or indirectly by rolling an ingot on a slabbing mill. Slabs are usually further processed via flat rolling, skelping, and pipe rolling. Common final products include sheet metal, plates, strip

metal A metal () is a material that, when polished or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, electricity and thermal conductivity, heat relatively well. These properties are all associated wit ...

, pipes, and tubes. Slab are mainly produced through blast furnace route. One of the reasons to preferably produce slab through BF route is to achieve high quality. Global Steel Slab Market Outlook
''Commodity Inside''. 16-08-2018. File:CC-OXY.jpg, An oxygen gas torch cutting a slab File:Slabs stack.jpg, Steel slabs

References

{{reflist Casting (manufacturing) Metalworking terminology