Iron and Steel Industry in Ancient India
Iron and Steel Industry in Ancient India
While the Indus civilization belonged to the Bronze Age, its successor, the Ganges civilization, which emerged in the first millennium BCE (Before Common Era), belonged to the Iron Age. Making of iron by smelting of the iron ore was practiced in ancient India. The iron and steel produced in early days was also shaped into useful articles. The primacy of iron technology in the Indian subcontinent is well established and there are several published books on the state of ancient Indian iron technology. Shshruta who was an authority on medical science in ancient India had described many surgical instruments in his book (third or fourth century BCE).
The testimony of the craftsmanship and antiquity of Indian iron and steel industry is visible from the iron objects belonging to the BCE period found from the burial sites at Adichinallur in Tinnevelly district in Tamil Nadu. Ancient Tinnevally district comprised present Tirunelveli and Thoothukudi districts and parts of Virudhunagar and Ramanathapuram districts. Some of the early iron objects found are dated to 1400 BCE by employing radio–carbon dating. Spikes, knives, daggers, arrow-heads, bowls, spoons, sauce-pans, axes, chisels, tongs, door fittings etc. ranging from 600 BCE – 200 BCE have been discovered at several archaeological sites. In southern India (present day Mysore), iron appeared as early as the 12th or 11th century BCE. These developments were too early for any significant close contact with the north-west of the country.
The beginning of the 1st millennium BCE saw extensive developments in iron metallurgy in India. Technological advancement and mastery of iron metallurgy was achieved during this period of peaceful settlements. The years between 322 BCE – 185 BCE saw several advancements made to the technology involved in metallurgy during the politically stable Maurya period (322 BCE – 185 BCE). Greek historian Herodotus (431 BCE – 425 BCE) wrote the first western account of the use of iron in India. One can find many descriptions of swords, daggers, spears, and other steel weapons in a number of ancient Indian literatures. Iron technology has grown steadily in ancient India and Indian iron and steel products were in great demand.
Recent excavations in central parts of the Ganges valley and in the eastern Vindhya hills have shown that iron was produced there possibly as early as in 1800 BCE. Its use appears to have become widespread from about 1000 BCE and the Vedic texts mentions of a ‘dark metal’ (krṣnāyas). Iron smelting and the use of iron was especially well established in the south Indian megalithic cultures of this period. The discovery of the Naikund furnace dating to 700 BCE attests to early smelting of iron (Fig 1). Near the furnace arrowhead, chisels, fish hook and other iron objects have been found. The traditional iron smelting is still practiced by tribal communities such as the Agarias in Madhya Pradesh and Chhattisgarh.
Perhaps as early as 300 BCE, although certainly by 200 CE (Common Era), high quality steel was being produced in southern India by what Europeans would later call the crucible technique. Using this technology, high-purity wrought iron, charcoal, and glass were mixed in a crucible and heated until the iron melted and absorbed the carbon. The first crucible steel was the wootz steel which originated in India before the beginning of the Common Era.
The superior corrosion resistance of the Indian iron produced during these periods is quite evident although the chemical composition is not much different than the iron samples from Japan and Iran etc. All the above clearly suggest that India was in the forefront of making iron and steel objects and the iron steel industry in India was remarkable in quality as well as forging and welding of heavy objects.
Iron technology reached significant heights during the Gupta period. Wootz, a very special kind of crucible steel, also known as Damascus steel was originally produced in India sometimes around the opening of the Common Era or may be even earlier. India has mastered the production of wootz steel from which world famous tough swords were manufactured. Archaeological evidence suggests that this manufacturing process was already in existence in south India well before the Common Era.
Iron in ancient India was extracted by the direct process. The iron-rich ores were reduced by means of charcoal and the end product was almost pure iron (with entrapped slag particles). These wrought iron lumps were generally utilized for making several useful objects. The iron lumps were carbonized by the crucible process in order to produce wootz steel. The property of carbon steels was strictly controlled by decarburizing and tempering treatments. During the medieval period , wootz steel was widely exported from India and traded in enormous quantities throughout ancient Europe, China, and the Arab world, and became particularly famous in the Middle East, where it became known as Damascus steel. This was because the technology for the production of such steels was considered to be the best in India. Typical ancient furnaces for extracting iron from iron ores are shown in Fig 1.
Fig 1 Typical ancient furnaces for extracting iron from iron ores
India was a major innovator in the field, producing two highly advanced types of iron. The first, wootz steel, produced in south India from about 300 BCE, was iron carburized under controlled conditions. Exported from the Deccan all the way to Syria, it was shaped there into ‘Damascus swords’ renowned for their sharpness and toughness. But it is likely that the term ‘Damascus’ derived not from Syria’s capital city, but from the ‘damask’ or wavy pattern characteristic of the surface of those swords. In any case, this Indian steel was called ‘the wonder material of the Orient’.
A Roman historian, Quintius Curtius, recorded that among the gifts which Alexander of Macedon received from Porus of Taxila (in 326 BCE), there was some two-and-a-half tons of wootz steel which was evidently more highly prized than gold or jewels. Later, the Arabs fashioned it into swords and other weapons, and during the Crusades, Europeans were overawed by the superior Damascus swords. It remained a favoured metal for weapons through the Moghul era, when wootz swords, knives and armours were artistically embellished with carvings and inlays of brass, silver and gold. In the armouries of Golconda and Hyderabad’s Nizams, Tipu Sultan, Ranjit Singh, the Rajputs and the Marathas, wootz weapons had pride of place.
Wootz steel is primarily iron containing a high proportion of carbon (1 % to 1.9 %). Thus the term wootz (an English rendering of ‘ukku’, a Kannada word for steel) applies to a high-carbon alloy produced by crucible process. The basic process consisted in first preparing sponge (or porous) iron; it was then hammered while hot to expel slag, broken up, then sealed with wood chips or charcoal in closed crucibles (clay containers) that were heated, causing the iron to absorb appreciable amounts of carbon; the crucibles were then cooled, with solidified ingot of wootz steel remaining. Right from the 17th century, several European travellers documented India’s iron and steel-making furnaces (Francis Buchanan’s accounts of south India are an important source of information as regards wootz).
The swords manufactured in Indian workshops are mentioned in the written works of Muhammad al-Idrisi (flourished 1154). Indian swords made of wootz steel found their way into Persia. During the 14th century, European scholars studied Indian casting and metallurgy technology. Indian metallurgy under the Mughal emperor Akbar (1556 – 1605) produced excellent small firearms. Mughal handguns were found to be stronger and more accurate than their European counterparts. In 1667, it has been estimated 5 tons of steel, and 25 tons of ironware was exported from India. While the Dutch are reported to have exported 46 tons of wootz steel during the 17th century from India. Typical swords and daggers made of wootz steel are shown in Fig 2.
Fig 2 Ancient swords and daggers made from wootz steel
The Delhi iron pillar
The second advanced iron is the one used in the famous 1,600 year old Delhi iron pillar, which, at a height of 7.67 m, consists of about six tons of wrought iron. It was initially erected by ‘Chandra as a standard of Vishnu at Vishnupadagiri’, according to a six-line Sanskrit inscription on its surface. ‘Vishnupadagiri’ has been identified with modern Udayagiri near Sanchi in Madhya Pradesh, and ‘Chandra’ with the Gupta emperor, Chandragupta II Vikramaditya (375 CE – 414 CE). In 1233, the pillar was brought to its current location in the courtyard of the Quwwat-ul Islam mosque in New Delhi’s Qutub complex, where millions continue to come and see this ‘rustless wonder’.
But why it is rustless, or, more precisely, rust-resistant. Here again, numerous experts, both Indian and Western, tried to grasp the secret of the pillar’s manufacture. Only recently its rust-resistant properties have been fully explained. These are mainly due to the presence of phosphorus in the iron. This element, together with iron and oxygen from the air, contributes to the formation of a thin protective passive coating on the surface, which gets reconstituted if damaged by scratching. It goes to the credit of Indian blacksmiths that through patient trial and error they were able to select the right type of iron ore and process it in the right way for such monumental pillars. Delhi Iron Pillar, with a close-up of the inscription is shown in Fig 3.
Fig 3 The Delhi Iron Pillar, with a close-up of the inscription
There are a few more such pillars in India. The iron pillar at Dhar, Madhya Pradesh (12th century CE) weighing 7 tons. The Iron pillar at Kodachadri hill (12th century CE) is of about 40 feet length is planted erect in front of Moola Mookambika temple near peak of Kodachadri and it is compared with massive similar historic iron pillars located at Dhar, Mount Abu etc. The Tanginath temple of lord Shiva (12th century CE) in Jharkhand has a centuries old trident (‘trishool’) of rustproof iron. Besides, the same technology was used to manufacture huge iron beams used in some temples of Odisha, such as Jagannath of Puri (12th century). The iron beams at Konark’s famous sun temple (9th century CE) are of even larger dimensions. Chemical analysis of one of the beams confirmed that it was wrought iron of a phosphoric nature (99.64 % Fe, 0.15 % P, traces of C, traces of S and no manganese). A large numbers of guns were made during 16th and 17th centuries CE. Some of these guns weigh over 35 tons.
Start of modern Iron and steel industry
In the year 1830, Mr. Joshua Marshall Heath had set up a small iron plant at Porto Novo on Madras coast. Heath produced in his plant pig iron at the rate of forty tons a week. His method of iron making needed around four tons of charcoal to produce one ton of low quality pig iron which proved to be too expensive for Heath to carry on in the face of stiff competition from the British steel industry.
The first notable attempt to revive steel industry in India was made in 1874, when the Bengal Iron Works (BIW) came into being at Kulti, near Asansol in West Bengal. The BIW made considerable improvement in the process of iron and steel making. It used coke as the fuel instead of charcoal. But the plant fell sick as the source of funds dried up. It was taken over by the Bengal government and was renamed as Barakar Iron Works. In 1889 the Bengal Iron and Steel Company acquired the plant and by the turn of the century, the Kulti plant became a success story. It produced 40,000 tons of pig iron in 1900 and continued to produce the metal until it was taken over by Indian Iron and Steel Company (IISCO) in 1936. In 1918, soon after the war, IISCO (Indian Iron and Steel Company) was formed. IISCO started producing pig iron at Burnpur in 1922. The Bengal Iron Works went into liquidation and merged with IISCO. The Steel Corporation of Bengal (SCOB) formed on 20 April, 1937, with Burn & Co. as managing agents. SCOB established steel making facilities at Napuria, adjacent to the Hirapur Works of IISCO. The new steel plant had an annual capacity of 250,000 tons of ingot steel. Another 100,000 tons were added later. The steel works consisted of three 225 ton tilting open hearth furnaces, soaking pits, a 40 inch blooming mill of one million ton capacity, a 34 inch heavy structural mill and an 18 inch light structural mill. A sheet mill was added in 1940. The first heat of steel was tapped on 10 November 1939 and rolled subsequently. A duplex plant initially with two Bessemer converters (and subsequently another) was added. The first blow of the Bessemer converter was made on 6 February 1946. Martin and Burn companies formally merged in 1946 to form Martin Burn Limited. Later in 1953, SCOB merged with IISCO. Two photographs of IISCO plant are at Fig 4.
Fig 4 India first blast furnace (open top) with coke oven battery in the foreground at Kulti and at right lighting coke oven battery by Chairman Biren Mookerjee at Burnpur
Kulti Works of IISCO had grown to be a major foundry complex in stages. The light castings foundry was established in 1881, general castings shop in 1915, non-ferrous foundry in 1948, steel foundry and heavy mechanized foundry in 1958. The spun pipe plants (three in number) came up in 1944, 1958 and 1981. The iron making facilities were closed down at Kulti in 1958 and it was decided to supply foundry iron in liquid form from Burnpur. Thus the curtain came down on 83-year long tradition of iron making at Kulti.
The modern iron and steel industry in India owes its origin to the grand vision and perseverance of Jamshetji Nusserwanji Tata. TISCO (The Tata Iron and Steel Company) was formed as a Swadeshi venture and was registered in Bombay on 26th August 1907. Construction of the TISCO plant at Sakchi (renamed Jamshedpur) in Bihar started in 1908 with American help. The first blast furnace was blown in on 2nd December 2011 and the first ingot was rolled on 16th February 1912 (right bottom of Fig 5). The plant was originally constructed for a capacity of 160,000 tons of pig iron, 100,000 tons of ingot steel, 70,000 tons of rails beams and shapes, and 20,000 tons of bars, hoops and rods. The plant consisted of 180 non recovery coke ovens, 30 numbers by-product ovens with a sulphuric acid plant, 2 numbers blast furnaces each with a capacity of 350 tons per day, a 300 tons hot metal mixer, 4 numbers 40 tons capacity open hearth furnaces, one steam engine driven 40 inch reversing blooming mill, one 28 inch reversing rail and structural mill and one 16 inch and 2 numbers 10 inch rolling mills. The plant has a power house, a well equipped laboratory and auxiliary facilities. The cost of the plant as erected was around Rupees 23 millions. Some of the photographs of the TISCO plant are at Fig 5.
Fig 5 Production of first Ingot at TISCO
There were enormous initial problems in clearing the Sakchi site and, once production began, in ensuring that the coal was of a uniform quality. However, by 1916, production was meeting expectations and during World War I the company exported 1,500 miles of steel rails to Mesopotamia. During the World War I (1914-1918), the company made rapid progress. TISCO emerged from the 1930s as the biggest steel plant in the British Empire. World War II brought resurgence in demand for the products of TISCO and the company specialized in the manufacture of armoured cars, known as ‘Tatanagars’, which were used extensively by the British Army in the North African desert. Following six years of almost continuous production to serve the war effort, it became imperative in the late 1940s to begin replacement of plant. In association with Kaiser Engineering of the United States, capacity was expanded and a modernization and expansion program (MEP) was launched in 1951, upgraded four years later to the two million ton project (TMP) to give TISCO the capacity to produce two million tons of crude steel per annum. This was achieved in 1958.
Visvesvaraya Iron and Steel Limited (VISL) started as the Mysore Iron Works on 18th January 1923. The Iron works was started by Nalvadi Krishnaraja Wodeyar, the King of Mysore, under the guidance of his Diwan Sir M Visvesvaraya. The main objective was to tap the rich iron ore deposits near Kemmanagundi in the Baba Budangiri hills and manufacture pig iron and other products. A preliminary investigation of setting up an iron and steel factory at Bhadravathi was done in 1915-1916. This investigation was done by a New York based firm who explored the possibility of manufacturing pig iron with the use of charcoal fuel. The years 1918-1922 were spent in setting up the factory. To start with, a wood distillation plant for manufacturing charcoal and blast furnace for smelting iron were set up in the factory. In 1952, two electric pig-iron furnaces were installed in the company, thereby making VISL the first iron and steel company in India to use electricity in the smelting of iron ore. A production shop of Visvesvaraya Iron and Steel Limited is shown in Fig 6.
Fig 6 A production shop of Visvesvaraya Iron and Steel Limited