Chafery

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A chafery is a variety of hearth used in ironmaking for reheating a bloom of iron, in the course of its being drawn out into a bar of wrought iron.

Wrought iron iron alloy with a very low carbon content

Wrought iron is an iron alloy with a very low carbon content in contrast to cast iron. It is a semi-fused mass of iron with fibrous slag inclusions, which gives it a "grain" resembling wood that is visible when it is etched or bent to the point of failure. Wrought iron is tough, malleable, ductile, corrosion-resistant and easily welded. Before the development of effective methods of steelmaking and the availability of large quantities of steel, wrought iron was the most common form of malleable iron. It was given the name wrought because it was hammered, rolled or otherwise worked while hot enough to expel molten slag. The modern functional equivalent of wrought iron is mild or low carbon steel. Neither wrought iron nor mild steel contain enough carbon to be hardenable by heating and quenching.

The equivalent term for a bloomery was string hearth, except in 17th century Cumbria, where the terminology was that of the finery forge.

Bloomery early form of iron smelter

A bloomery is a type of furnace once used widely for smelting iron from its oxides. The bloomery was the earliest form of smelter capable of smelting iron. A bloomery's product is a porous mass of iron and slag called a bloom. This mix of slag and iron in the bloom is termed sponge iron, which is usually consolidated and further forged into wrought iron. The bloomery has now largely been superseded by the blast furnace, which produces pig iron.

Cumbria Ceremonial (geographic) county of England

Cumbria is a ceremonial and non-metropolitan county in North West England. The county and Cumbria County Council, its local government, came into existence in 1974 after the passage of the Local Government Act 1972. Cumbria's county town is Carlisle, in the north of the county, and the only other major urban area is Barrow-in-Furness on the southwestern tip of the county.

A finery forge for the Walloon process would typically have one chafery to work two fineries (but sometimes one or three fineries).

Finery forge

A finery forge is a hearth used to fine wrought iron, through the decarburization of the pig iron. The fining process involved liquifying cast iron in a fining hearth and removing carbon from the molten cast iron through oxidation. Finery forges were used as early as 3rd century BC, based on archaeological evidence found at a site in Tieshengguo, China. The finery forge process was replaced by the puddling process and the roller mill, both developed by Henry Cort in 1783-4, but not becoming widespread until after 1800.

Wallonia Region of Belgium

Wallonia is a region of Belgium. As the southern portion of the country, Wallonia is primarily French-speaking, and accounts for 55% of Belgium's territory and a third of its population. The Walloon Region was not merged with the French Community of Belgium, which is the political entity responsible for matters related mainly to culture and education, because the French Community of Belgium encompasses both Wallonia and the majority French-Speaking Brussels-Capital Region. The German-speaking minority in eastern Wallonia results from WWI and the subsequent annexation of three cantons that were initially part of the former German empire. This community represents less than 1% of the Belgian population. It forms the German-speaking Community of Belgium, which has its own government and parliament for culture-related issues.

Chaferies were also used in the potting and stamping forges of the industrial revolution.

Potting and stamping is a modern name for one of the 18th century processes for refining pig iron without the use of charcoal.

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Forge workplace of a blacksmith

A forge is a type of hearth used for heating metals, or the workplace (smithy) where such a hearth is located. The forge is used by the smith to heat a piece of metal to a temperature where it becomes easier to shape by forging, or to the point where work hardening no longer occurs. The metal is transported to and from the forge using tongs, which are also used to hold the workpiece on the smithy's anvil while the smith works it with a hammer. Sometimes, such as when hardening steel or cooling the work so that it may be handled with bare hands, the workpiece is transported to the slack tub, which rapidly cools the workpiece in a large body of water. However, depending on the metal type, it may require an oil quench or a salt brine instead; many metals require more than plain water hardening. The slack tub also provides water to control the fire in the forge.

Pig iron iron alloy

Pig iron is an intermediate product of the iron industry, also known as crude iron, which is first obtained from a smelting furnace in the form of oblong blocks. Pig iron has a very high carbon content, typically 3.8–4.7%, along with silica and other constituents of dross, which makes it very brittle and not useful directly as a material except for limited applications. Pig iron is made by smelting iron ore into a transportable ingot of impure high carbon-content iron in a blast furnace as an ingredient for further processing steps. The traditional shape of the molds used for pig iron ingots was a branching structure formed in sand, with many individual ingots at right angles to a central channel or runner, resembling a litter of piglets being suckled by a sow. When the metal had cooled and hardened, the smaller ingots were simply broken from the runner, hence the name pig iron. As pig iron is intended for remelting, the uneven size of the ingots and the inclusion of small amounts of sand caused only insignificant problems considering the ease of casting and handling them.

Steelmaking process for producing steel from iron ore and scrap

Steelmaking is the process for producing steel from iron ore and scrap. In steelmaking, impurities such as nitrogen, silicon, phosphorus, sulfur and excess carbon are removed from the raw iron, and alloying elements such as manganese, nickel, chromium and vanadium are added to produce different grades of steel. Limiting dissolved gases such as nitrogen and oxygen, and entrained impurities in the steel is also important to ensure the quality of the products cast from the liquid steel.

Wealden iron industry

The Wealden iron industry was located in the Weald of south-eastern England. It was formerly an important industry, producing a large proportion of the bar iron made in England in the 16th century and most British cannon until about 1770. Ironmaking in the Weald used ironstone from various clay beds, and was fuelled by charcoal made from trees in the heavily wooded landscape. The industry in the Weald declined when ironmaking began to be fuelled by coke made from coal, which does not occur accessibly in the area.

Open hearth furnace

Open hearth furnaces are one of a number of kinds of furnace where excess carbon and other impurities are burnt out of pig iron to produce steel. Since steel is difficult to manufacture due to its high melting point, normal fuels and furnaces were insufficient and the open hearth furnace was developed to overcome this difficulty. Compared to Bessemer steel, which it displaced, its main advantages were that it did not expose the steel to excessive nitrogen, was easier to control, and it permitted the melting and refining of large amounts of scrap iron and steel.

Ironworks building or site where iron is smelted

An ironworks or iron works is a building or site where iron is smelted and where heavy iron and steel products are made. The term is both singular and plural, i.e. the singular of ironworks is ironworks.

Halton-with-Aughton civil parish in Lancaster, Lancashire, England

Halton-with-Aughton is a civil parish and electoral ward located 3 miles (5 km) east of Lancaster, England, on the north bank of the River Lune. The main settlement is the village of Halton, commonly just called Halton, in the west, and the parish stretches to the hamlet of Aughton in the east. It lies in the City of Lancaster district of Lancashire, and has a population of 2,227, down from 2,360 in 2001.

In American Colonial history, the Iron Act, short-titled the Importation, etc. Act 1750, was one of the legislative measures introduced by the British Parliament, within its system of Trade and Navigation Acts. The Act sought to increase the importation of pig and bar iron from its American colonies and to prevent the building of iron-related production facilities within these colonies, particularly in North America where these raw materials were identified. The dual purpose of the act was to increase manufacturing capacity within Great Britain itself, and to limit potential competition from the colonies possessing the raw materials.

A forge is the hearth where the blacksmith keeps the fire for heating metals to be formed by plastic deformation, usually with hammer on an anvil.

Puddling (metallurgy) metallurgical process

Puddling was one step in one of the most important processes of making the first appreciable volumes of high-grade bar iron during the Industrial Revolution. In the original puddling technique, molten iron in a reverberatory furnace was stirred with rods, which were consumed in the process. It was one of the first processes for making bar iron without charcoal in Europe, although much earlier coal-based processes had existed in China. Eventually, the furnace would be used to make small quantities of specialty steels.

Hammer mill

A hammer mill, hammer forge or hammer works was a workshop in the pre-industrial era that was typically used to manufacture semi-finished, wrought iron products or, sometimes, finished agricultural or mining tools, or military weapons. The feature that gave its name to these workshops was the water-driven trip hammer, or set of hammers, used in the process. The shaft, or 'helve', of the hammer was pivoted in the middle and the hammer head was lifted by the action of cams set on a rotating camshaft that periodically depressed the end of the shaft. As it rose and fell, the head of the hammer described an arc. The face of the hammer was made of iron for durability.

Tuyere

A tuyere or tuyère is a tube, nozzle or pipe through which air is blown into a furnace or hearth.

Osmond process

Osmond iron was wrought iron made by a particular process. This is associated with the first European production of cast iron in furnaces such as Lapphyttan in Sweden.

In metallurgy, refining consists of purifying an impure metal. It is to be distinguished from other processes such as smelting and calcining in that those two involve a chemical change to the raw material, whereas in refining, the final material is usually identical chemically to the original one, only it is purer. The processes used are of many types, including pyrometallurgical and hydrometallurgical techniques.

Oregrounds iron

Oregrounds iron was a grade of iron that was regarded as the best grade available in 18th century England. The term was derived from the small Swedish city of Öregrund, the port from which the bar iron was shipped. The process to create it is known as the Walloon method.

Lancashire hearth

The Lancashire hearth was used to fine pig iron, removing carbon to produce wrought iron.