sâmbătă, 24 aprilie 2010

220 years from the commissioning of the blast furnace from Toplita

Economic premises
Due to the development of the productive forces during the 18th century, especially its second half, there appeared in Transylvania the ever more evident signs of the feudalism crisis. The entire evolution of metallurgy in that period has to be considered by taking into account those economic conditions, with a special mention of the situation in Hunedoara county where the owner of the productive forces (beginning with the year 1725) was the state exclusively.
Following the measures undertaken by the Vienna Court in 1754, i.e. the taking over of the iron production from the leaseholders in order to administrate and control it, the metallurgical installations from Transylvania were rebuilt and new technologies were introduced. Those changes were characteristic for the iron shops from Hunedoara county. The old iron shops were revamped and their number increased by the middle of the 18th c. from 5 to 13.
The historic documents outlined that the iron from Hunedoara was highly appreciated and required in the neighboring Turkish provinces, excepting the periods of social disorders that troubled the economic relationships.
After 1771 the price of the iron increased from 4.5-5.0 florins to 7.40 florins for the quality iron. Consequently, the annual profit was 20,000 florins higher. During the good years, Hunedoara county obtained 63-65,000 florins which were sent to the central pay office of Alba Iulia where all the income taxes were being collected. In 1772 the income was probably of over 200,000 florins.
We have no data about the origins of the iron shops: but we know for sure that in the whole county there existed only one high furnace, at Toplita, on the Cerna river. In 1778 that blast furnace was mentioned as being operational and having good results. It can be assumed that the state had built Toplita blast furnace at the same time with those from Rhonic and Tiszolc following the good results obtained by the blast furnaces from Dobsina and Betler. The high furnaces from Rhonic and Tiszolc are known to have been operating in 1750; consequently we can assume that the blast furnace from Toplita had also been built around 1750. In the same region most of the iron shops mentioned in the Urbarium from 1754 were fully operating as annexes to that blast furnace.
Hunedoara was in a favorable situation as it was exempted from tricesima for the iron bought by the merchants from its warehouses and then transported through the Hateg valley to Baia Mare, Moldavia and Wallachia. Hunedoara estate was protected until 1765 against the iron imports from Hungary. Only the merchandise from Styria -Austria / could enter Transylvania. The iron consumption was limited almost exclusively in Transylvania to the domestic production. The administration of Hunedoara estate, Iosif Filip Kern considered that there was an iron shortage in Tansylvania caused by the Russian-Turkish war taking place in Moldavia and Wallachia of which the Saxon merchants from Sibiu and Brasov profited a lot. After taking into account the complaints of the administrator Iosif Filip Kern, the court from Vienna decreeted that beginning with 1772 iron could not be exported anymore in Moldavia and Wallachia unless there existed an authorization issued by Hunedoara estate or by the warehouses and only out of the iron surplus that remained unsold on the domestic markets. Under that decree the exemption from the custom duty for the iron coming from Hunedoara was suspended.
Due to the important reserves of iron ores from Ghelar and Teliuc, to the rich forests (source of charcoal) and especially to the strong tradition of the Woodsmen in processing the iron, the first blast furnace was built in Toplita, in Cerna Valley. Still in that period, the administrator of Hunedoara estate, Iosif Filip Kern opened an iron mine in Teliuc .
The beginnings of the blast furnace construction
The documents of that epoch don't mention anything about putting into operation the first blast furnace at Toplita, on the Cerna Valley, at 15 km upstream of Hunedoara. It is possible that the blast furnace had started in 1754 since the Urbarium of that year mentioned that the New Shop or Baia Noua, placed near the high furnace, was the first shop in that region where the iron was extracted from pig iron (it had four furnaces for refining the iron). In the Cerna Valley there were shops where both the iron obtained from ore and the pig iron which was refined in open hearths were processed . It's hard to believe that the pig iron used in those shops were brought from other regions because of the big distances that existed between the high furnaces from Banat (they were rather far away from Toplita).
Therefore we should assume that the blast furnace from Toplita was already been functioning at an early date than the one mentioned in the historical documents.
The first document that presents precise data about the blast furnace, dated from 1787, writes down the fact that during that year the blast furnace was operating with 112 double shifts of 12 hours. During that time, 27826 Viennese majas and 88 fonts (1563.9 to) of ore were processed, out of which 9431 majas (528 to) of pig iron resulted. The yield was of 33.75 fonts of pig iron (18.9 kg) obtained out of one maja of ore, with an average production of 84 majas and 33 fonts (4.72 to) per day. That year the blast furnace was stopped and repaired twice, because of the severe wear of the hearth .
On the 4th of October 1780 four workers from Hunedoara were sent to Styria - Austria for learning the new working practices . Zaharia Pascu the furnaceman was among them . In the spring of the year 1780 the administrators of Hunedoara county undertook a series of measures in order to begin the construction works at a blast furnace (or to rebuilt a new one ). The documents mention that on March the 1st, 1780, 20,000 tiles of wood (for covering the shop) were bought and tools for the construction works were prepared . The construction at Toplita began on March 15th 1780, with 130 workers by preparing the place where the blast furnace was to be built . For raising the buildings a great amount of wooden material was necessary. In March other 200 workers were hired but the snow that still covered the mountains prevented the workers from cutting and stacking the wood . For the transportation of planks, tiles and stones, 1658 florins were paid.
Once finished the preparation for the construction , they were looking for a specialist in blast furnaces (Flossofen) whose presence was indispensable for beginning the work. . Edlinger, a head master from Styria, accepted after negotiations to come to Hunedoara for participating at putting the blast furnace into service .
On January 18th 1781, the Treasury Office from Sibiu asked the Chamber from Vienna to send master Edlinger to Hunedoara by the end of March, so that the blast furnace were put into operation by the beginning of June . The two specialists, master Edlinger and Zaharia Pascu who had been trained in Styria, came at Hunedoara on March the 31st 1784. The Styrian master was satisfied with the location of the blast furnace and the quality of the works. Edlinger decided together with the administrators of the county to use stones from the neighborhood of Toplita for building the furnace shell. The hearth was made out of clay . On June the 21st 1781 after having been ill for ten days, Edlinger passed away. The construction works continued under the supervision of the administrator, Mr. Matsch and of Zaharia Pascu . The latter was controlling effectively the whole production process. They succeeded to put the blast furnace into operation on July 13th, 1781.
Constructive and operational data
The main technical characteristics and dimensions of the blast furnace, extracted from historic documents, were the following:
 Working volume: 6.94 m3;
 Total height: 21 feet (6.64 m);
 Hearth diameter at the bottom: 2 feet and 4 inches (0.735 m);
 Bosh diameter: 5 feet (1.58 m);
 The height of the bosh above the hearth (Upper bosh line at): 2.42 m;
 Blast furnace throat diameter: 2 feet (0.632 m);
 The height up to the first tuyère: 18 inches (0.479 m);
 The height up to the second tuyère: 36 inches (0.948 m);
 The height up to which the annual repair work was done: 60 inches (1.58 m);
 Charcoal consumption was of about 1905 kg/to hot metal.
The blast furnace hearth was a little bit inclined towards the tapping hole so that the discharging of the liquid products from the hearth were easier.
Every tuyère was fed with air via two leather bellows driven by a hydraulic wheel having an inner width of 4 feet (1.264 m) and a length of 3 feet and 3 inches (1.057 m). The bellows gave 6-7 blows/min. each and when the flow rate of the river Cerna diminished, especially during hot summers, they gave only 4-5 blows/minute . The blast furnace was entirely lined with cut stone.
The time table for the blast furnace presents data concerning the consumption of raw materials and the production obtained in 1781 .

Period of time Shifts Ore (majas) Coal (burden) Production (majas)
21…23.08 33 1087.70 794 335.5
02…06.09 10 475.96 313 151.71
09…19.09 25 1071.64 706 340.90
26.09…13.10 14 684.74 452 218.43
03…04.10 2 140.16 98 55.50
05…25.10 44 2851.38 1616 1050.10
25.10…31.12 105 6999.9 3970 2722.40
Total 233 13310.67 7940 4875

In order to satisfy the ever increasing demand for pig iron, the Chamber from Vienna asked the Administration of the estate to increase the height of Toplita blast furnace, a practice already used in other countries. The construction works were finished in the spring of the year 1805. The new working volume of the furnace was of 10.91 cm , according to a document dated from 1830, and its main dimensions were the following:
 Total height: 21 feet and 6 inches (6.79 m);
 Hearth diameter at the bottom: 34 inches (0.946 m);
 Bosh diameter: 65 inches (1.817 m);
 The height up to the first tuyère: 18 inches (0.479 m);
 The height up to the second tuyère: 20 inches (0.526 m);
 Blast furnace throat diameter: 34 inches (0.946 m).

The raw materials used in the blast furnace
For elaborating a heat they used ores from mines and pits, iron recovered from slag and additions. To all that, coal of beech wood was added. The coals discovered in the neighboring region called Valea Jiului were introduced in the charge in the year 1770 . At the beginning they didn't obtain remarkable results since the charcoal was not of the best quality and there were big expenses implied by the transportation on the rather bad roads of that time. On December 9th 1836, the Treasury Office from Transylvania ordered a research to be made for establishing why the coals used in the blast furnace and in the refining furnaces were of bad quality . The bad quality of iron ores and coals and the insufficient knowledge of the refining process were the cause of wastes. The administration of the Toplita blast furnace admitted in 1836 that only poor quality bars were produced out of the pig iron obtained from the mine ores .
In 1836 the administration of Hunedoara estate presented a clear report of the wastes from the blast furnace, iron shops and warehouses, of the causes that lead to producing them and of the possibilities of being rendered profitable. In the documents they mentioned that the amount of wastes was caused by the attempt of obtaining the biggest production of white pig iron ever possible and by the temperature of the tapped iron .
The administration of the estate carried out some researches for discovering in the neighborhood of Toplita a rock to be used for lining the blast furnace.

The pig iron output and its commercialization
The production of the blast furnace was maintained at a constant level. A document from 1799 mentioned a weekly production of 604 - 692 majas (33.8 - 38.8 to), at a yield of 37.25 - 40.50% . The pig iron which was to be refined in the neighboring iron shops was poured in blocks. Usually the blast furnace produced white pig iron for being refined, but also gray cast iron or gray spiegel iron when needed. Thus, between 1801- 1802, 90% of the pig iron was white, 7.5% was gray and 2.5% gray spiegel iron. Beginning with the year 1808, the blast furnace also produced pieces cast directly from the furnace, in ever increasing quantities, up to 50 to/year. From the existing data it results that the production was fluctuant, presenting big variations from one year to another, depending on the supplying possibilities and the repair works needed. Thus, 528 to were produced in 1787, 1400 to in 1802 and in 1836 a peak output of 2460 to was registered. Very low outputs were obtained in 1794 (187.5 to) and in 1813 (23.8 to), respectively in the years when general overhauls were done to the blast furnace.
The whole output of the blast furnace was sent to the iron shops from Hunedoara estate and to other iron shops outside the estate. The New Shop (built near to the blast furnace) and also the shops from Teliuc, Toplita (the old shop), Limpert and Nadrab and those from Sibisel and Cugir would soon abandon the old method of extracting the iron directly from the ores. They would produce iron and steel by refining the pig iron supplied exclusively by the blast furnace from Toplita.
The blast furnace stopped operating due to a fire that broke out on the night of 15-16th of January 1837 and destroyed the building, the installations and the materials from the warehouses .

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