steel industry glossary of terms

Glossary Term	Glossary Explanation
Killed steel	Steel that has its oxygen content reduced - typically through addition of aluminium. Hence the term aluminium killed
Ladle metallurgy	A process step typically applied in a ladle furnace for alloying, deoxidation, desulphurisation as well as for temperature adjustment prior to casting of quality steels
Large diameter pipe	Definition in size terms varies but trade and other statistics frequently define large diameter pipe as over 16 inches (or 406.4mm) in diameter. Large pipe of this size is invariably welded rather than seamless, and can be produced by longitudinal or spiral welding for applications that often include gas and oil transport
LME	London Metal Exchange - leading non-ferrous metals market in the UK
Long ton	Measure of weight used in the UK prior to metrication. The long ton is equivalent to 2240 pounds or approximately 1016 kg. See also under glossary term short ton and tonne below
Merchant bar	A category of light long products comprising steel bars shaped as rounds, squares, hexagonals, rectangles, flats etc used mainly as support structures for building, construction, machinery. Merchant bar is to be distinguished from reinforcing bar (which is used to reinforce concrete) and from engineering steel (which often ends up moving rather than being stationery)
MHPT	Man hours per tonne - a common measure of labour force or process productivity
Micum index	The percentages of coke remaining in a given size-band after rotating a coke sample within a drum for a given time. The index is a measure of the strength of coke against both impact and abrasion
Midrex ®	Direct reduction process for converting iron ore into direct reduced iron (DRI) for iron and steelmaking
Mild steel	Low carbon steel - often also referred to as soft steel. Carbon content generally under 0.25%
Mini mill	The term 'minimill' normally refers to a scrap-based EAF route steelmaking operation of relatively small scale (usually less than 500 kt capacity / year; thus much smaller than a typical BOF plant making several million t/yr) producing long products - although the concept is increasingly finding application in flat product mills. The word 'mini' is applied both because of the relatively small scale in volume terms and because of the relatively low capital cost per tonne involved in construction [broadly ~$250/t for a minimill versus ~$1000/t for an integrated plant]
National Allocation Plans, NAPs	Facility lists prepared by EU Member States that specify [by country] key installations and their CO2 emission limits
NACE	End-use industry classification system used in the European Union
NDT	Non-destructive testing - refers to electronic or other methods of inspection that do not permanently affect the properties of the material
Nickel pigs	Iron units made from low grade pig iron produced from laterite ore (0.9% to 1.9% nickel). When the cost of refined nickel rose steeply in 2006, these 'pigs' came into popularity (especially in China) in attempts to offset high stainless steel production costs
Normalising	Heat treatment for relief of internal stress, based on heating and subsequent air cooling
OCS	Organic coated sheet
OCTG	Oil country tubular goods - refers to the group of steel tube products (both seamless and welded) used in vertical oil well applications such as casing, drill pipe, and well tubing
OHF	Open hearth [Siemens-Martin] steelmaking furnace, use of which has now been largely superseded by higher productivity / more efficient BOF and EAF steelmaking processes. Using a hearth with a low roof, molten pig iron and scrap in the hearth are heated by overhead gas burners using preheated air to produce steel
Old environmental burdens	Refer to liabilities for past environmental damage, often caused during periods of previous State-ownership. In the main, the damage concerns that caused to the soil and to groundwater
Organic coated	Organic coating refers to paint or varnish which is added as an extra corrosion protection layer to products typically made from zinc-coated sheet

STEEL INDUSTRY GLOSSARY OF TERMS

Technical jargon made simple