The ores used for the manufacture of this iron are mostly from the celebrated mines of Maloblagodatj, and average about the following chemical composition: Metallic iron 60 per cent, silica 5 per cent, phosphorus from 0.15 to 0.06 per cent. The ore is generally smelted into coal pig-iron and converted into malleable iron by puddling or by a Franche-Comté hearth. Frequently, however, the malleable iron is made directly from the ore in various kinds of bloomaries. The blooms or billets thus obtained are rolled into bars 6 inches wide, 1/4" inch thick, and 30 inches in length. These bars are assorted, the inferior ones "piled" re-rolled whilst the others are carefully heated to redness and cross-rolled into sheets about 30 inches square, requiring from eight to ten passes through the rolls. These sheets are twice again heated to redness and rolled in sets of three each, care being taken that every sheet before being passed through the rolls is brushed off with a wet broom made of fir, and at the same time that powdered charcoal is dexterously sprinkled between the sheets. Ten passes are thus made, and the resulting sheets trimmed to a standard size of 25 by 56 inches. After being assorted and the defective ones thrown out, each sheet is wetted with water, dusted with charcoal powder and dried. They are then made into packets containing from 60 to 100, and bound up with the waste sheets. The packets are placed one at a time, with a log of wood at each of the four sides in a nearly air-tight chamber, and carefully annealed for five or six hours. When this has been completed the packet is removed and hammered with a trip hammer weighing about a ton, the area of its striking surface being about 6 by 14 inches. The face of the hammer is made of this somewhat unusual shape in order to secure a wavey appearance on the surface of the packet. After the packet has received ninety blows equally distributed over its surface it is reheated and the hammering repeated in the same manner. Some time after the first hammering the packet is broken and the sheets wetted with a mop to harden the surface. After the second hammering the packet is broken, the sheets examined to ascertain if any are welded together, and completely finished cold sheets are placed alternately between those of the packet, thus making a large packet of from 140 to 200 sheets. It is supposed that the interposition of these cold sheets produces the peculiar greenish color that the finished sheets posses on cooling. This large packet is then given what is known as the finishing or polishing hammering. For this purpose the trip hammer used has a larger face than the others, having an area about 17 by 21 inches. When the hammering has been properly done, the packet has received 60 blows equally distributed, and the sheets should have a perfectly smooth, mirror-like surface. The packet is now broken before cooling, each sheet cleaned with a wet fir broom to remove the remaining charcoal powder, carefully inspected, an the good sheets stood on their edges in vertical racks to cool. These sheets are trimmed to regulation size (28 by 56 inches) and assorted into Nos. 1, 2, 3, according to their appearance, and again assorted according to weight, which varies from 10 to 12 lbs. per sheet. The quality varies according to color, and freedom from flaws or spots. A first-class sheet must be without the slightest flaw and a peculiar metallic gray color, and on bending a number of times with the fingers, very little or no scale is separated, as in the case of ordinary sheet iron. The peculiar property of Russian sheet iron is the beautiful polished coating of oxides ("glanz") which it possesses. If there is any secret in the process, it 1probably lies in the "trick" of giving this polish. As far as I was able to judge, from personal observation and conversation with the Russian iron masters, the excellence of this sheet iron appeared to be due to no secret, but to a variety of conditions peculiar to and nearly always present in the Russian iron works of the Urals. Besides the few particulars already noted in the above description of this process, it should be borne in mind that the iron ores of the Urals are particularly pure, and that the fuel used is exclusively charcoal and wood. Another, and equally as important consideration, lies in the fact that this same process of manufacturing sheet iron has been carried on in the Urals for the last hundred years. As a consequence, the workmen have acquired a peculiar skill, the want of which has made attempts to manufacture equally as good iron outside of Russia generally less successful. It is difficult to understand what effect the use of charcoal powder between the sheets as they are rolled and hammered has upon the quality. It is equally as difficult to understand the effect of the interposition of the cold finished sheets upon the production of the polished coating of oxide. The Russian iron master seem to attribute the excellence of their product more to this peculiar treatmentthan to any other cause. One thing is quite certain, there is no secret about the process, and if the Russian sheet iron is so much superior to any other, it is due to the combination causes already indicated.
Hoi Ronald,Ziet er top uit ... ook de wagon, waar inderdaad nog andere draaistellen onder moeten ... Groet,Jeroen
"Baby, make my day....."
Begint er op te lijken, voor de restjes die er nog op zitten gaat alles nog een dag (of misschien 2) in de alcohol.
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