Investors within the steel sector frequently encounter terms for example slab, hot dip galvanised sheet, or coated sheet – however the definitions of those terms and interrelationships between your different steel products within the production chain are in no way always obvious. In the following paragraphs, the authors describe the steel product ‘production’ chain and also the flow of merchandise from semi-finished to end product.
The 3 Semi-End Product Groups
The 3 primary finished steel product groups are tube, flat products and lengthy products. These finished goods are created from semi-finished steel items that are often produced by continuous casting of liquid steel. These so-known as semis comprise,
billet: typically a square some 6 or 12 metres long with mix-sectional section of 100 – 120 mm square to no more than 180 – 200 mm square – employed for lengthy products and seamless tube
slab: usually as much as 12 metres long and conventionally from ~150 mm as much as ~400 mm thick – employed for flat products (and subsequently, welded tube)
blossom: usually above 180 or 200mm square close to 300 – 360 mm square (to no more than ~400 mm square) – employed for large section and lengthy products.
The Finished Products
Embracing the various end product groups,
billet is generally hot-folded into light lengthy products. These items generally comprise bar – which may be round, square, angled etc. This light lengthy category frequently includes merchant bar products (models, squares, hexagons, rectangles, flats etc used mainly as support structures for building, construction, machinery) in addition to reinforcing bar (typically 8 – 18 mm across, and employed for concrete reinforcement). Light lengthy products may also include wire fishing rod, that is generally under 13.5 mm across, and it is created in coils instead of lengths. Steel wire, steel mesh, nails along with other fasteners are usually produced from wire fishing rod.
slab is generally hot folded into plate or into hot folded coil. Beyond this task, there’s cold moving, which often takes hot folded steel coil and additional cuts down on the gauge to create cold-folded coil. Cold-folded steel can be used such (e.g. in machine components), but is frequently coated to create zinc coated sheet or tin plate. Zinc coated sheet is frequently processed further still – to create so-known as organic coated sheet – in which a plastic coating further increases the anti-corrosive qualities from the steel.
blossom is usually folded inside a blooming mill, to create large sections or huge bar shapes.
welded tube consequently is generally produced by bending of hot folded coil or sheet (produced from slab) although plate or cold-folded steel may also be used for welded tube making with respect to the preferred wall thickness.
seamless tube is generally produced by billet piercing.
The steel production process chain in conclusion therefore, usually includes the next steps:
manufacture of liquid steel
manufacture of semis
hot moving of semis to create light lengthy products such bar or hot folded plate or coil
cold moving from the hot folded bar or coil product, to create cold-folded coil or cold attracted products for example steel wire.