Iron Making

The aim of this paper is to find out the patterns of incidents in a steel plant in India. Occupational incidents occur in steel plant mainly in form of injury, near miss, and property damage or in combination. Different factors are responsible for such incidents to occur. An incident investigation scheme is proposed. Association rule mining approach is used to discover cause-and-affect patterns (rules) using 843 incidents. Thirty-five meaningful association rules are extracted using three criteria, support (S), confidence (C) and lift (L). For example, the results show that unsafe acts done by others are more frequent in injury cases (S = 4.86%, C = 78.8%, L = 2.3). Similarly, one of the SOP (standard operating procedures) related rule: ‘SOP required, available, adequate but not complied’ led to property damage (S = 11.03%, C = 49.2%, L = 1.525). Another useful rule ‘SOP required, available but inadequate, followed’ led to near miss (S = 1.66%, C = 38.89%, L = 1.163). It is also found that for slip, trip and fall incidents, workers working alone (S = 3.91%, C = 76.74%, L = 2.239) or in a group (S = 3.20%, C = 75.00%, L = 2.188) does not make much difference. The findings pinpoint the areas of improvement such as inadequate SOPs, non-compliance of SOPs, training, and slip, trip and fall prevention to minimize incidents.

Norwegian Bloomery iron-making research got a strong resurgence in the wake of the historical investigations that took place in 1980's, at the forefront of energy development of the river Dokka Oppland. Arne Espelund, now retired professor of process metallurgy, Institute of Metal Technology - NTNU, was one of those who supported the project-members with the preparation of metallurgical analyses. Espelund has spent the years that followed, until today, to support historical museums, ironworks enthusiasts and heritage management in Norway with analyses of iron ore, slag and metal.
Espelund has his own cultural and historical platform from which one he has sought to convey preindustrial iron production. His communication was done through practical education projects in schools, participation in research debate related to prehistoric bloomery. He has given lectures in archaeometallurgy environments both in Norway and internationally. Not least,  is it from his hand written many articles in various European languages. Now last, he has written a monograph in English, The evidence and the secrets of old Bloomery ironmaking in Norway, 2013.
His new book builds on the same concept as his previous books, but the professional issues are drawn with a multifaceted brush. The presented book is aimed at a mixed group of people, ranging from metallurgists and archaeologists to blacksmiths, and also to person it may concern in the many historical associations in Norway.

He claims that he refrains from subject studies, but claims too that he will approach and focus on the object, the iron production furnace, bloom and slagheap. The book's text does not satisfy Espelunds own vision for this monograph, but exposes and circles mainly around his own performances.

Somogyfajsz- Ívató tó (1988, 1995). In the pit-workshop 16 metres in diameter, 21 iron-smelting furnaces were dug out. The diameter of the bottom of the furnaces built into the side of the workshop are 35-40 centimetres in average. Their inner areas are pear-shaped, and their inner height could be about 70 centimetres. The clay furnaces are similar to the Imola-type iron smelting furnaces in their size and form. However, differently from the Imola-type furnaces, because for Somogyfajsz-type furnaces there are breast walls (including a twyer) for the blowing.
Two main periods of use can be observed at the iron smelting place. The work pit no. I. was built in a dip on a 6 x 8 meters area. The entry of the pit opened to the brook. From the same direction, the furnaces sunk into the wall of the workshop were blown. After wearing out the furnaces of the old workshop, it was enlarged by an other pit of the same size. At the same time, the middle of the work pit no. I. was gradually filled in by the by-products of iron smelting furnaces built  later. Only the hearths remained from the furnaces, demolished at the enlargement of work pit no. I. (furnaces no. 1-13.). During the use of work pit no. II., the northern part of work pit I. was also enlarged by building new furnaces (Furnaces no. 5-6, 10-11, 14-15.). In this pit, furnace no. 6 was used last. Next to and in front of it, four blooms weighing 1,6 to 3,6 kilograms have been found.  Work pit no. II, which is shown in its original form in the Museum of ancient  furnaces (Őskohó Múzeum), forms a round-cornered square, with 6 meter long sides. Its entry is on the east from work pit no. I. The furnaces stood along the southern, western and northern walls, 3 metres from one another. So blowing with bellows was possible at the three furnaces at the same time. Supplying the charcoal and the ore was possible through the mouth. The black charcoal spots and the red spots with granular ore with a diameter of  about 100 centimetres, shows the place of the piles of the raw material and fuel, at the edge of the work pit.
One of the iron smelters worked outside the work pit, at the edge of the pit, his mate blew with the bellows. This working system assumes that the workshop had not got any walls, at most there was only a temporary roof, which post-holes did not remain. On the basis of the 500 twyers found there, at least 500 smelting could be presumed. If one smelting resulted in 2,5 kilogram iron or steel, the furnace produced 1250 kilograms iron. One furnace could produced 20 blooms from 50 smelting, that means that one furnace produced 50 kilograms iron altogether. So many smelting could have not been possible only two furnaces, so the number of them must have been more.
Age determination: Relative chronology: Among the furnaces of work pit no. II., the one with no. 19 was in use last, which was built instead of the furnace no. 21. In the furnace no. 18, iron-smelting took place several times, so it was burnt through more, and was more damaged. Furnace no. 17, though it was almost intact similarly to the furnace no. 19, was partly covered by the waste,  from furnaces no. 18 and 19. The burnt through furnace no. 20 was used earlier. Opposite to it, there is supposed to be an other furnace under a slag pile.
The output of iron went on at least for a decade on this site. The sudden leave of the iron-smelting site proved by the round iron blooms around the furnace no. 6. and the erected but never used smelting furnaces. It is supposed that the iron smelters left the workshop after 997, the revolt of Koppány dux, the owner of the workshop, against István Grand duke (later king Stephan I.).
Absolute chronology: On the basis of the decoration of the pottery, the iron smelting furnaces of Somogyfajsz is dated to the 10th-11th century, possibly to the end of the 10th century. Furnace no. 2. 14C: 882 - 982 (888-966), 796 - 1006 AD, furnace no. 3 .: 14C: 898 - 916 (900-910), 947 - 1016, 878 - 1038 , 1104 - 1108 AD, furnace no.4: 14C: (900- 910), 947 - 1016, (954 - 1016) AD (after Ede Hertelendi, Debrecen, ATOMKI); Archaeomagnetic: the beginning of the 11th century AD (after Péter Márton, ELTE Geophysical department).