Pig Iron comprises three main types: BASIC PIG IRON, used mainly in electric arc steelmaking, FOUNDRY PIG IRON used in mainly in the manufacture of grey iron castings in cupola furnaces, and NODULAR PIG IRON (SG GRADE) used in the manufacture of ductile iron castings. An intermediate product of puddling is known as refined pig iron, finers metal, or refined iron. Due to the chemical combination of carbon content, the casting is achieved easily with lower consumption of energy. 2. Pig iron is classified on the basis of contents of free and combined carbon as follows. 1. Pig iron has a very high carbon content, typically 3.8–4.7%,[1] along with silica and other constituents of dross, which makes it very brittle and not useful directly as a material except for limited applications.[2]. Pig Iron is made by melting iron, charcoal and limestone together through extreme air pressure. Modern steel mills and direct-reduction iron plants transfer the molten iron to a ladle for immediate use in the steel making furnaces or cast it into pigs on a pig-casting machine for reuse or resale. Grey pig iron (Grades 1, 2 and 3) Grey pig iron contains about 3% carbon in free form (i.e., graphite form) and about 1% carbon in combined form. The cold pig iron is known as merchant pig iron, which is cast into blocks or ingots. Pig iron was not produced in Europe before the Middle Ages. Modern pig casting machines produce stick pigs, which break into smaller 4–10 kg piglets at discharge. Pig iron is an output obtained as a result of the process of manufacturing iron. The impurities of pig iron are removed to some extent by oxidation. Until recently, pig iron was typically poured directly out of the bottom of the blast furnace through a trough into a ladle car for transfer to the steel mill in mostly liquid form; in this state, the pig iron was referred to as hot metal. Earlier processes for this included the finery forge, the puddling furnace, the Bessemer process, and the open hearth furnace. This type of pig iron is produced from the specific sources of iron ore. Due to the stable physical as well as chemical analysis it enables the variability of melting and a robust control over the composition of final casting. White pig iron (Grades 4) The molten cast iron is led into moulds of required shapes to form what are known as cast iron castings and slag is removed from the top of cast iron at regular intervals. "REMINISCENCES OF THE EARLY ANTHRACITE-IRON INDUSTRY", https://www.persee.fr/doc/befeo_0336-1519_1995_num_82_1_2347, https://en.wikipedia.org/w/index.php?title=Pig_iron&oldid=986561208, Creative Commons Attribution-ShareAlike License, This page was last edited on 1 November 2020, at 16:47. There are several grades specified in various standards based on Si and Mn content of the pig iron. Pig Iron comprises three main types: BASIC PIG IRON, used mainly in electric arc steelmaking, FOUNDRY PIG IRON used in mainly in the manufacture of grey iron castings in cupola furnaces, and NODULAR PIG IRON (SG GRADE) used in the manufacture of ductile iron castings. This is highly beneficial for the thin-walled castings. The hot metal was then poured into a steelmaking vessel to produce steel, typically an electric arc furnace, induction furnace or basic oxygen furnace, where the excess carbon is burned off and the alloy composition controlled. This type of pig iron is mainly used for steel making. Obtaining Other Metals from Pig Iron. Smelting and producing wrought iron was known in ancient Europe and the Middle East, but it was produced in bloomeries by direct reduction. This is a soft type of pig iron. This eradicates the need for the high-priced casting requirements like heat treatment. Pig iron can also be used to produce gray iron. Grey pig iron (Grades 1, 2 and 3) Grey pig iron contains about 3% carbon in free form (i.e., graphite form) and about 1% carbon in combined form. Pig iron is classified on the basis of contents of free and combined carbon as follows. The presence of the other metal impurities is also negligible that makes the iron highly desirable in various sectors. Pig iron and cast iron are different types of metal. Traditionally, pig iron was worked into wrought iron in finery forges, later puddling furnaces, and more recently, into steel. Pig iron is used for steel making, Foundries, Alloy making, in automotive castings and other iron based castings. This type of pig iron is also known as HPPI and is characterized by its lower contents of sulfur, phosphorus, and manganese. There are three types of merchant pig iron, which are as follows: Attributes and Application of Foundry Pig Iron for the Grey Iron Casting. Pig iron is an unrefined product that has been converted from iron ore, one step in the process to create steel. White pig iron (Grades 4) Attributes and Application of High Purity Pig Iron for the Ductile Iron Casting. An intermediate product of puddling is known as refined pig iron, finers metal, or refined iron.[9]. Pig iron is the product of smelting iron ore (also ilmenite) with a high-carbon fuel and reductant such as coke, usually with limestone as a flux. This is achieved by remelting pig iron, often along with substantial quantities of steel and scrap iron, removing undesirable contaminants, adding alloys, and adjusting the carbon content. Basic grade – Basic pig iron has less than 1.0 % silicon, under 1 % manganese, and trace amounts of sulphur and phosphorous. The phase transition of the iron into liquid in the furnace was an avoided phenomenon, as decarburizing the pig iron into steel was an extremely tedious process using medieval technology. These classifications are also termed as grades. Pig iron, crude iron obtained directly from the blast furnace and cast in molds.