A wound may be defined as a 'breach of continuity in the structures of the body, whether external or internal, suddenly occasioned by mechanical violence.' The law does not define 'a wound,' but the true skin must be broken. Wounds are dan... Read more of Wounds And Mechanical Injuries at Forensic Medicine.caInformational Site Network Informational
Privacy
   Home - Steel Making - Categories - Manufacturing and the Economy of Machinery

Steel Making

Detrimental Elements
Sulphur and phosphorus are two elements known to be detrimen...

A Chromium-cobalt Steel
The Latrobe Steel Company make a high-speed steel without tun...

Restoring Overheated Steel
The effect of heat treatment on overheated steel is shown gra...

Testing And Inspection Of Heat Treatment
The hard parts of the gear must be so hard that a new mill f...

Sulphur
Sulphur is another impurity and high sulphur is even a greate...

Nickel
Nickel may be considered as the toughest among the non-rare a...

The Pyrometer And Its Use
In the heat treatment of steel, it has become absolutely nece...

Gas Consumption For Carburizing
Although the advantages offered by the gas-fired furnace for ...

Cyanide Bath For Tool Steels
All high-carbon tool steels are heated in a cyanide bath. Wi...

Tensile Properties
Strength of a metal is usually expressed in the number of pou...

Temperature For Annealing
Theoretically, annealing should be accomplished at a tempera...

Case-hardening Treatments For Various Steels
Plain water, salt water and linseed oil are the three most co...

Double Annealing
Water annealing consists in heating the piece, allowing it to...

Tool Or Crucible Steel
Crucible steel can be annealed either in muffled furnace or b...

Heat Treatment Of Punches And Dies Shears Taps Etc
HEATING.--The degree to which tools of the above classes shou...

An Automatic Temperature Control Pyrometer
Automatic temperature control instruments are similar to the ...

Annealing To Relieve Internal Stresses
Work quenched from a high temperature and not afterward tempe...

High Speed Steel
For centuries the secret art of making tool steel was handed ...

Annealing Of High-speed Steel
For annealing high-speed steel, some makers recommend using g...

Connecting Rods
The material used for all connecting rods on the Liberty engi...



Steel Before The 1850's








In spite of a rapid increase in the use of machines and the
overwhelming demand for iron products for the expanding railroads, the
use of steel had expanded little prior to 1855. The methods of
production were still largely those of a century earlier. Slow
preparation of the steel by cementation or in crucibles meant a
disproportionate consumption of fuel and a resulting high cost.
Production in small quantities prevented the adoption of steel in uses
which required large initial masses of metal. Steel was, in fact, a
luxury product.

The work of Reaumur and, especially, of Huntsman, whose development of
cast steel after 1740 secured an international reputation for
Sheffield, had established the cementation and crucible processes as
the primary source of cast steel, for nearly 100 years. Josiah Marshall
Heath's patents of 1839, were the first developments in the direction
of cheaper steel, his process leading to a reduction of from 30 to 40
percent in the price of good steel in the Sheffield market.[4] Heath's
secret was the addition to the charge of from 1 to 3 percent of
carburet of manganese[5] as a deoxidizer. Heath's failure to word his
patent so as to cover also his method of producing carburet of
manganese led to the effective breakdown of that patent and to the
general adoption of his process without payment of license or royalty.
In spite of this reduction in the cost of its production, steel
remained, until after the midpoint of the century, an insignificant
item in the output of the iron and steel industry, being used
principally in the manufacture of cutlery and edge tools.

[4] Andrew Ure, Dictionary of arts, manufactures and mines, New
York, 1856, p. 735.

[5] See abridgement of British patent 8021 of 1839 quoted by
James S. Jeans, Steel, London, 1880, p. 28 ff. It is not clear
that Heath was aware of the precise chemical effect of the use of
manganese in this way.

The stimulus towards new methods of making steel and, indeed, of making
new steels came curiously enough from outside the established industry,
from a man who was not an ironmaster--Henry Bessemer. The way in which
Bessemer challenged the trade was itself unusual. There are few cases
in which a stranger to an industry has taken the risk of giving a
description of a new process in a public forum like a meeting of the
British Association for the Advancement of Science. He challenged the
trade, not only to attack his theories but to produce evidence from
their own plants that they could provide an alternative means of
satisfying an emergent demand. Whether or not Bessemer is entitled to
claim priority of invention, one can but agree with the ironmaster who
said:[6] "Mr. Bessemer has raised such a spirit of enquiry throughout
... the land as must lead to an improved system of manufacture."

[6] Mining Journal, 1857, vol. 27, p. 465.


Bessemer and his Competitors

Henry Bessemer (1813-1898), an Englishman of French extraction, was the
son of a mechanical engineer with a special interest in metallurgy. His
environment and his unusual ability to synthesize his observation and
experience enabled Bessemer to begin a career of invention by
registering his first patent at the age of 25. His active experimenting
continued until his death, although the public record of his results
ended with a patent issued on the day before his seventieth birthday. A
total of 117 British patents[7] bear his name, not all of them, by any
means, successful in the sense of producing a substantial income.
Curiously, Bessemer's financial stability was assured by the success of
an invention he did not patent. This was a process of making bronze
powder and gold paint, until the 1830's a secret held in Germany.
Bessemer's substitute for an expensive imported product, in the then
state of the patent laws, would have failed to give him an adequate
reward if he had been unable to keep his process secret. To assure this
reward, he had to design, assemble, and organize a plant capable of
operation with a minimum of hired labor and with close security
control. The fact that he kept the method secret for 40 years, suggests
that his machinery[8] (Bessemer describes it as virtually automatic in
operation) represented an appreciation of coordinated design greatly in
advance of his time. His experience must have directly contributed to
his conception of his steel process not as a metallurgical trick but as
an industrial process; for when the time came, Bessemer patented his
discovery as a process rather than as a formula.

[7] Sir Henry Bessemer, F.R.S., an autobiography, London, 1905,
p. 332.

[8] Ibid., p. 59 ff.

In the light of subsequent developments, it is necessary to consider
Bessemer's attitude toward the patent privilege. He describes his
secret gold paint as an example of "what the public has had to pay for
not being able to give ... security to the inventor" in a situation
where the production of the material "could not be identified as having
been made by any particular form of mechanism."[9] The inability to
obtain a patent over the method of production meant that the disclosure
of his formula, necessary for patent specification, would openly invite
competitors, including the Germans, to evolve their own techniques.
Bessemer concludes:[10]

Had the invention been patented, it would have become public
property in fourteen years from the date of the patent, after which
period the public would have been able to buy bronze powder at its
present [i.e., ca. 1890] market price, viz. from two shillings
and three pence to two shillings and nine pence per pound. But this
important secret was kept for about thirty-five years and the
public had to pay excessively high prices for twenty-one years
longer than they would have done had the invention become public
property in fourteen years, as it would have been if patented. Even
this does not represent all the disadvantages resulting from secret
manufacture. While every detail of production was a profound
secret, there were no improvements made by the outside public in
any one of the machines employed during the whole thirty-five
years; whereas during the fourteen years, if the invention had been
patented, there would, in all probability have been many improved
machines invented and many novel features applied to totally
different manufactures.

[9] Ibid., p. 82.

[10] Ibid., p. 83.

While these words, to some extent, were the rationalizations of an old
man, Bessemer's career showed that his philosophy had a practical
foundation; and, if this was indeed his belief, the episode explains in
large measure Bessemer's later insistence on the legal niceties of the
patent procedure. The effect of this will be seen.

Bessemer's intervention in the field of iron and steel was preceded by
a period of experiments in the manufacture of glass. Here Bessemer
claims to have made glass for the first time in the open hearth of a
reverberatory furnace.[11] His work in glass manufacture at least gave
him considerable experience in the problems of fusion under high
temperatures and provided some support for his later claim that in
applying the reverberatory furnace to the manufacture of malleable iron
as described in his first patent of January 1855, he had in some manner
anticipated the work of C. W. Siemens and Emil Martin.[12]

[11] Ibid., p. 108 ff.

[12] Ibid., p. 141. Bessemer's assertion that he had approached
"within measurable distance" of anticipating the Siemens-Martin
process, made in a paper presented at a meeting of the American
Society of Mechanical Engineers (Transactions of the American
Society of Mechanical Engineers, 1897, vol. 28, p. 459), evoked
strong criticism of Bessemer's lack of generosity (ibid., p.
482). One commentator, friendly to Bessemer, put it that
"Bessemer's relation to the open-hearth process was very much
like Kelly's to the Bessemer process.... Although he was
measurably near to the open-hearth process, he did not follow it
up and make it a commercial success...." (ibid., p. 491).

The general interest in problems of ordnance and armor, stimulated by
the Crimean War (1854-1856), was shared by Bessemer, whose ingenuity
soon produced a design for a projectile which could provide its own
rotation when fired from a smooth-bore gun.[13] Bessemer's failure to
interest the British War Office in the idea led him to submit his
design to the Emperor Napoleon III. Trials made with the encouragement
of the Emperor showed the inadequacy of the cast-iron guns of the
period to deal with the heavier shot; and Bessemer was presented with a
new problem which, with "the open mind which derived from a limited
knowledge of the metallurgy of war," he attacked with impetuosity.
Within three weeks of his experiments in France, he had applied for a
patent for "Improvements in the Manufacture of Iron and Steel."[14]
This covered the fusion of steel with pig or cast iron and, though this
must be regarded as only the first practical step toward the Bessemer
process,[15] it was his experiments with the furnace which provided
Bessemer with the idea for his later developments.

[13] British patent 2489, November 24, 1854.

[14] Bessemer, op. cit. (footnote 7), p. 137 He received
British patent 66, dated January 10, 1855.

[15] See James W. Dredge, "Henry Bessemer 1813-1898,"
Transactions of the American Society of Mechanical Engineers,
1898, vol. 19, p. 911.

These were described in his patent dated October 17, 1855 (British
patent 2321). This patent is significant to the present study because
his application for an American patent, based on similar
specifications, led to the interference of William Kelly and to the
subsequent denial of the American patent.[16] In British patent 2321
Bessemer proposed to convert his steel in crucibles, arranged in a
suitable furnace and each having a vertical tuyere, through which air
under pressure was forced through the molten metal. As Dredge[17]
points out, Bessemer's association of the air blast with the increase
in the temperature of the metal "showed his appreciation of the end in
view, and the general way of attaining it, though his mechanical
details were still crude and imperfect."

[16] See U.S. Patent Office, Decision of Commissioner of Patents,
dated April 13, 1857, in Kelly vs. Bessemer Interference. This is
further discussed below (p. 42).

[17] Dredge, op. cit. (footnote 15), p. 912.


IN U.S. PATENT 16082. This patent, dated November 11, 1856, corresponds
with British patent 356, dated February 12, 1856. The more familiar
design of converter appeared first in British patent 578, March 1,
1860. The contrast with Kelly's schematic drawing in Fig. 2 (p. 42) is
noticeable.]

Experiments were continued and several more British patents were
applied for before Bessemer made his appearance before the British
Association on August 13, 1856.[18] Bessemer described his first
converter and its operation in some detail. Although he was soon to
realize that he "too readily allowed myself to bring my inventions
under public notice,"[19] Bessemer had now thrown out a challenge which
eventually had to be taken up, regardless of the strength of the vested
interests involved. The provocation came from his claims that the
product of the first stage of the conversion was the equivalent of
charcoal iron, the processes following the smelting being conducted
without contact with, or the use of, any mineral fuel; and that further
blowing could be used to produce any quality of metal, that is, a steel
with any desired percentage of carbon. Yet, the principal irritant to
the complacency of the ironmaster must have been Bessemer's attack on
an industry which had gone on increasing the size of its smelting
furnaces, thus improving the uniformity of its pig-iron, without
modifying the puddling process, which at best could handle no more than
400 to 500 pounds of iron at a time, divided into the "homeopathic
doses" of 70 or 80 pounds capable of being handled by human labor.[20]
Bessemer's claim to "do" 800 pounds of metal in 30 minutes against the
puddling furnace's output of 500 pounds in two hours was calculated to
arouse the opposition of those who feared the loss of capital invested
in puddling furnaces and of those who suspected that their jobs might
be in jeopardy. The ensuing criticism of Bessemer has to be
interpreted, therefore, with this in mind; not by any means was it
entirely based on objective consideration of the method or the
product.[21]

[18] Bessemer's paper was reported in The Times, London, August
14, 1856. By the time the Transactions of the British Association
were prepared for publication, the controversy aroused by
Bessemer's claim to manufacture "malleable iron and steel without
fuel" had broken out and it was decided not to report the paper.
Dredge (op. cit., footnote 15, p. 915) describes this decision
as "sagacious."

[19] Bessemer, op. cit. (footnote 7), p. 164.

[20] The Times, London, August 14, 1856.

[21] David Mushet recognized that Bessemer's great feature was
this effort to "raise the after processes ... to a level
commensurate with the preceding case" (Mining Journal, 1856, p.
599).

Within a month of his address, Bessemer had sold licenses to several
ironmasters (outside Sheffield) and so provided himself with capital
with which to continue his development work; but he refused to sell his
patents outright to the Ebbw Vale Iron Works and by this action, as
will be seen, he created an enemy for himself.

The three years between 1856 and 1859, when Bessemer opened his own
steel works in Sheffield, were occupied in tracing the causes of his
initial difficulties. There was continued controversy in the technical
press. Bessemer (unless he used a nom-de-plume) took no part in it
and remained silent until he made another public appearance before the
Institution of Civil Engineers in London (May 1859). By this time
Bessemer's process was accepted as a practical one, and the claims of
Robert Mushet to share in his achievement was becoming clamorous.





Next: Robert Mushet

Previous: Protectors For Thermo-couples



Add to del.icio.us Add to Reddit Add to Digg Add to Del.icio.us Add to Google Add to Twitter Add to Stumble Upon
Add to Informational Site Network
Report
Privacy
SHAREADD TO EBOOK


Viewed 2976