Rus′sia sheet-i′ron.
Sheet-iron made in
Russia, and having a smooth, glossy surface of a purplish color, sometimes mottled.
The process has been long supposed to be a secret, or it has been supposed that certain secret compositions are used.
There may be some truth in this, and it does not appear that all the manufactories follow exactly the same order of treatment.
The process has been observed by many travelers, among whom may be cited
Pumpelly.
One authority states that the metal is not subjected to any secret process, but that the iron is, in the first place, a very pure article, rendered exceedingly tough and flexible by refining and annealing.
Its peculiar surface is a combined silicate and oxide of iron, produced by passing the hot sheet, moistened with a solution of wood ashes, between polished steel rollers.
Most of the attempts to imitate the
Russia sheetiron have been to give it a surface of carburet of iron.
Probably the most reliable description accessible is that given by
Captain Meshtcherkin, a Russian mining-engineer conversant with the manufacture, to
Dr. Percy.
According to this officer, the manufacture is principally confined to the eastern or Asiatic side of the
Ural Mountains.
Charcoal iron from magnetic ore, carbonate, or red and brown hematite, and refined in the charcoal finery or the puddlingfurnace, is employed.
It should be rather crystalline than fibrous, and contain sufficient carbon to render it somewhat “steely.”
The puddle-halls are rolled into bars 5 inches wide by 1/4 inch thick.
Either one or two pairs of rolls, making not less than 50 revolutions per minute, are employed.
The sheets are extended under a trip-hammer (
a,
Fig. 4507) having a wrought-iron head faced with steel, and weighing about 60 poods (2,160 pounds): the anvil is of white cast-iron; both should be quite hard.
Another trip-hammer (
b), having a broader face, weighing 40 to 50 poods (1,440 to 1,800 pounds), attached to a lever fulcrumed more nearly at the center than the first, is employed in polishing.
The reheating furnace is shown in section at
c and in plan at
d. The fireplace
e extends under the bed of the reheating-chamber
f from end to end, and the gaseous products of combustion are carried into the chamber through five equal openings
g on each side, and are finally carried off by the chimney
h.
i are the gratebars, and
k k the doors of the fireplace and ash-pit.
l is the charging-door.
This and the other doors are made as tight as possible, in order to prevent access of air to the plates being heated.
Wood is the fuel used, and some of this also surrounds the pile in the reheating-chamber.
The puddle-bars are cut into strips 29 inches in length, which are then heated to redness and cross-rolled some 12 or 14 times, until they are about 29 inches square.
The sheets thus produced are then cleansed with a wet broom, arranged in packets of three, and passed through the rolls about ten times, powdered charcoal having been previously sprinkled in between them, and afterward sheared to the dimensions of 28, 56 inches. Each sheet is then brushed all over with a mixture of birch-charcoal powder and water.
From 70 to 100 sheets are made up into a packet
m, which is bound with waste sheets and slowly heated for 5 or 6 hours in the furnace, surrounded by logs of wood, in order to consume any free oxygen present.
The pile is then removed from the furnace and placed under the first hammer, being manipulated so that the blows fall upon it in successive rows from end to end. When it has been gone over about six
[
2006]
times in this way, it is removed and the sheets are alternated with some which are completely finished, making up a packet of from 140 to 200 sheets; these are subjected to the action of the second hammer, under which they are passed twice in a similar manner, which completes the smoothing process.
 |
|
Russia sheet-iron (hammers and furnaces) |
After the second hammering, the packet is opened, the surface of each sheet is again cleaned with a wet broom, and it is set in a vertical rack to cool: it is then sheared to the dimensions of 28 × 56 inches.
Professor Pumpelly, who witnessed the process employed in the works at Nijni Tagilsk, attributes the superiority of the
Russian product in great part to the cleanliness observed and the skill and carefulness of the workmen.
He states that when thin sheets are required, the rolling is repeated a third time in packages of four or six.
The spotted sheets are separated into two inferior classes, and their diminution in value is deducted from the workmen's pay.
The fire-proof bricks used in lining the furnace are made of a fine quartz sand, merely sprinkled with lime-water before being molded and burned.
By another account, the rollers used are not formed in a lathe, but cast at once of the requisite smoothness and regularity in molds rubbed over with graphite.
While the plates are being rolled, the edges are kept free from gaps by paring them with large shears.
They are then placed in packs of from 10 to 20 on a moving bench, which passes them to and fro under a hammer of 40 poods' weight; both sides are alternately exposed to its action, and a man carefully brushes off the scales that are continually produced on the surface.
The parings are mixed with half their weight of charcoal and converted into
bar-iron.
Herbert Barry, late
director of estates and ironworks of Vuicksa, thus describes the manufacture: —
The refined iron is hammered under the tilt-hammer into narrow slabs, calculated to produce a sheet of finished iron, 56 inches by 28 inches, weighing when finished from 6 to 12 pounds. These slabs are put in the reheating-furnaces, heated to a red heat, and rolled down to a sheet in three operations.
These are subsequently hammered to reduce the thickness and confer the
glance. A number of these sheets, having been again heated to a red heat, have charcoal-powder sifted between them.
The pile, then receiving covering and a bottom in shape of a sheet of thicker iron, is placed under a heavy hammer; the bundle, grasped with tongs by two men, is pulled backward and forward by the gang, so that every part may be well hammered.
When the redness goes off, they are finished, so far as this part of the operation goes, and have received some of the
glance or necessary polish.
They are then again heated and are rolled between cold finished sheets.
They are again hammered, and, after this process, are finished as far as thickness and
glance are concerned.
Thrown down separately to cool, they are taken to the shears and trimmed.
Each sheet is then weighed, and after being thus assorted in weights, they are finally sorted into firsts, seconds, and third, according to their
glance and freedom from flaws and spots.
A first-class sheet must be like a mirror, without a spot in it.
The general weight per sheet is from six to twelve pounds, the larger demand being from ten to eleven pounds; but they are made weighing as much as thirty pounds, and may then almost be called thin boiler-plates, being used for stoves, etc.
The appearance of
Russia iron is imparted to sheets (No. 22 wire gage) by dipping them while warm in a mixture, the consistency of molasses, of chalk, porcelain-clay, and graphite, in equal parts.
When dried, they are farther rolled and annealed, and afterward dipped in a pickle of 1 part sulphuric acid to 3 water till free from scales, then allowed to remain a short time in a lye of 1 potash to 20 water, filtered; afterward washed with clear water and smoked in an oven heated with light wood; the soot is burned off as the heat increases, and a carburet is formed on the surface with which it is closely combined.
The plates are now gradually permitted to cool, and then hammered or rolled and tempered in a tightly closed chamber lined with
fire-brick, when they may be again lightly hammered or passed through the polishing-rolls.
At the
sheet-iron works in
Brooklyn, an engine of 200 horsepower drives an automatic steam-hammer weighing seven tons.
The rolled
sheet-iron is greased and arranged in packages of thirty or more sheets.
Each sheet is about 2 1/2 feet wide and 7 feet long.
The packs are then run into an oven and exposed to heat until the surface has attained the proper degree of oxidation.
The packs are then transferred to the hammer, all the sheets in the pack being hammered at once.
The anvil is movable, and the workmen change the position of the pack at each stroke of the hammer, so that every portion of the iron will be acted upon.
At the
McKeesport Iron-Works,
Wood's process is used.
A heavy hammer falls vertically on the sheets with rapid blows as they are passed over an anvil, the face of the hammer and the anvil being pitted with small indentations.
It is the passage under this hammer that does the planishing, giving the even surface, mottled finish, and density of fiber which characterize the
Russian.
The charcoal iron is rolled into bars and cut, the scale is removed, after which it is rolled into sheets of different thicknesses, then cold rolled, then heated to a cherry-red, and passed under the planishing-hammer three sheets at a time.
The following are condensed descriptions of
United States patents for modes of making
sheet-iron similar to the
Russian:
No. 2,813,
Wood, 10, 12, 1842.
Rolled in usual manner, but left thicker; oxide removed by acid; cleaned and dried; coated with
linseed-oil; two such plates placed between two others; the pack heated to a cherry-red and rolled repeatedly till the gloss is obtained.
No. 2,824,
Guilford, 22, 10, 1842 Scale removed by acid; washed and dried; subjected to mutual friction in a box with lid and stampers; heated to blue color; passed, while hot, through hardened and polished rolls.
No. 8,048,
Wood, 15, 4, 1851.
Similar to No. 2,813, but the pack is rolled between shield-plates.
The latter eventually become inside plates, being scaled, oiled, heated, and rolled as the others.
Smoothed and glazed by cold rolling between shield-plates.
No. 9,075,
McCarty, 26, 6, 1852.
Plates are scaled by acid bath and zinc in a lead pan during effervescence; washed and dried; heated to cherry-red in a lead bath; rolled while hot; mottled marks given by hammer-dressing on the rolls.
English patent, No. 14,244, 1852.
The sheets are rolled, piled in fours, and rerolled, trimmed, heated, rolled in packs, heated, packed (20 sheets) with intervening charcoal, hammered with a 250-pound hammer; unpacked, packed (40 sheets) without charcoal, one hot and one cold sheet alternately; hammered by a 900-pound hammer; annealed and trimmed.
No. 10,047,
McCarty, 27, 9, 1853.
Planished rolls to give mottled marks to the iron sheets.
No. 10,482,
Pomeroy, 31, 1, 1854.
Iron plates painted with a composition of graphite, charcoal, and soot or boneblack, diluted with anything and put on with a brush; heat and roll.
No. 21,692,
Morris, 5, 10, 1858.
Making a mottled, chillediron roll for rolling
sheet-iron.
The rolls are chilled, turned, polished; dotted with wax according to taste; immersed in acid bath to etch in the intervals; placed in a lathe and rubbed with emery and oil to take off the sharp edges.
No. 21,772,
Morris, 12, 10, 1858.
Sheet-iron of carefully selected and prepared metal is passed between mottled rollers (as above), placed in a muffle, heated to redness in a furnace; made into a pack of ten, with intervening charcoal; the pack placed on an anvil, which is made to travel to and fro beneath a gang of hammers; reheated; rehammered; annealed.
No. 21, 817,
Chandler, 19, 10, 1858.
Sheets are rubbed with or dipped into a paste of clay or peat, and metallic oxides; rolled, cleaned, made into a pack, and rerolled.
No. 31,184,
Morris, 22, 1, 1861.
Rolled sheets are coated with oil, boxed, placed in a muffle, and heated to 900° Fah.; hammered in the pack to combine the carbonized scale and form a carbureted surface.
No. 32,341,
Wood, 14, 5, 1861.
Rolled sheets are annealed at a dull white heat; cooled; rolled between corrugated rolls to break scale, then between plain rolls; no acids; coat surface with oil and graphite; heat to bright red; roll in packs; rolls covered with oil and graphite.
No. 33,341,
Wood, 3, 9, 1861.
Rolled plates are warmed and dipped in a bath of water, chalk, porcelain-clay, and graphite; withdrawn and dried; pack of ten plates heated to bright red and rolled; acid bath to remove scale; alkaline bath to develop color; water bath; dried; heated in a smoky oven to cover sur-
[
2007]
face with carbon deposit, which becomes embodied in the iron; cooled; planished or rolled; tempered.
No. 33,214, Riess, 3, 9, 1861 Rolled plates are dipped in a bath of chalk, porcelain-clay, and graphite; dried, packed, heated, rolled, and annealed.
No. 33,844,
McDaniel and
Harvey, 3, 12, 1861.
Vacuum pressure in the removal of acid liquor, and subsequent alkaline treatment.
No. 34,294,
Dixon, 4, 2, 1862.
Rolled plates scaled by acid bath; washed with adhesive, or rye-water; swabbed at less than a red heat with an enamel composition; kept at that heat for ten hours in an oven; sheets placed in an annealing-box with interposed charcoal-dust, and heated; rolled in packs and annealed.
No. 46,974,
Pratt, 14, 2, 1865.
Sheet-metal immersed in acid bath at a prescribed heat; removed, scrubbed, and immersed in alkaline bath; brushed with rotary brushes while wet; heated to dryness; immersed in oil bath at 100° to 150° Fah.; dripped, and passed between polished steel-rollers; buffed by leather-rollers and chalk-dust; colored over charcoal furnace.
No. 48,918,
Ells, 25, 7, 1865 Sheets annealed; placed loosely in a cast-iron box, with scale of oxide, animal charcoal, coke, lime, or other decarbonizing or cutting agents; agitated while heated in the furnace.
No. 50,203,
Grey, 26, 9, 1865.
Heats the sheets previous to finishing; cools to a point below cherry-red; rolls without removing scale; repeats operation.
No. 52,647,
Perkins, 13, 2, 1866.
Cleans and brightens mechanically; then heats in an oven to develop color.
No. 53,476,
Perkins, 27, 3, 1866.
Sheets packed with intervening iron turnings; heated, rolled, annealed.
No. 53,253,
Allen and
Hinsdale, 20, 3, 1866.
A fagot of iron has top and bottom steel-plates; heated, rolled into a bar; bar rolled into sheets; oxide removed by acid bath; washed; a pack of ten heated to redness and rolled.
No. 56,759,
Jones,
Spaulding, and
Perkins, 31, 7, 1866.
The wrought-iron melted in a crucible with nitrate of lead, muriate of antimony, bone-dust, and graphite: stir; remove flux from the top; run into molds and roll as usual.
No. 61,034,
Wood, 8, 1, 1867.
After removing from the alkaline bath, and washing as usual in hot water, the plate is dried and heated in an oven below redness; dipped in a bath of oil and turpentine.
No. 63,805,
Miller, 16, 4, 1867.
The rolled sheet, before a final rolling, is heated nearly to welding point by gas-jets, above and below the plate, just before entering between the finishingrollers.
No. 77,111,
Shaw, 21, 4, 1868.
The heated iron, or the rolls, are mopped with a composition of graphite, animal fat, soda, and water.
No. 81,903,
Hinsdale, 8, 9, 1868.
The
bar-iron is scaled; washed; dipped in a bath of clay 100, lampblack 1, prussiate of potash .5; heated and rolled; the
sheet-iron is dipped in same composition and rerolled.
No. 88,002,
Atkins, 23, 3, 1869.
Roll into sheets, scale with acid, neutralize with lime-water, oil; lay up the iron in packs with intervening charcoal and marble dust; raise to a red-heat, roll singly; reheat, and roll in pairs, and so on; rolling till cold to develop polish; heat in packs to anneal; roll, and cool slowly.
No. 95,554,
Barker, 5, 10, 1869 Roll; remove scale by acid; wash; potash bath, in which they remain till rolled; roll in packs, cold; mottled rolls, made by a peculiar process of chill casting.
No. 98,364, Fields, 28, 12, 1869.
Iron is of Franklinite 100, good
pig-iron 400.
Sheet-iron is scaled; dipped in a bath of flour of zinc 1, graphite 1, tallow enough to make consistence of cream, when melted; a pack of three sheets is placed beneath a steam-hammer with a hard-wood face; the anvil having a similar face; grain of wood vertical.
No. 103,323,
Grey, 24, 5, 1871.
Scale removed by an acid bath and subsequent heating on racks in an oven to raise the scale in blisters.
A thin, tenacious oxide forms on the surface and is preserved.
Rolled cold, first singly, then in packs; annealed.
No. 103,577,
Craig, 31, 5, 1870.
Plates are built into packs with intervening charcoal-dust; heated nearly to welding heat; rolled in packs: reviving the metal of the superficial oxide.
No. 114,956,
Marshall, 16, 5, 1871.
Scale removed by
saline bath and furnace heating; dipped in lime-water; heated to cherry-red and rolled in packs; anneal.
