IMPROVE- MENTS IN THE MANUFACTURE OF STEEL, AND IN CASE HARDENING OR PARTIALLY CONVERTING IRON INTO STEEL
Year: 1873

page_text: LETTERS PATENT to James Pinley Sharp, of Birmingham, in the
County of Warwick, Tar Distiller, for the Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF STEEL, AND IN CASE HARDENING OR PARTIALLY
CONVERTING IRON INTO STEEL."
Scaled the 10th June 1873, and dated the 5th February 1873.
PROVISIONAL SPECIFICATION left by the said James Pinley Sharp
at the Office of the Commissioners of Patents, with his Petition, on
the 5th February 1873.
I, JAMES PINLEY SHARP, of Birmingham, in the County of Warwick,
Tar Distiller, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF STEEL, AND IN CASE HARDENING OR
PARTIALLY CONVERTING IRON INTO STEEL," to be as follows, that is to
say:
This Invention has for its object the production of steel with greater
accuracy and certainty as to quality than is attained by any of the
processes at present followed, so that an operator knowing the quality of

page_text: iron he is employing and the description of steel he desires to produce
may be enabled accurately to adjust the quantity of carbon by employing
such carbon in as nearly as possible its purest state and under conditions
favourable to its regular and equable absorption by the iron at the
moment the latter has attained the degree of heat most favourable for
its conversion; and my Invention embraces improvements in making
steel either by cementation or by casting, and as follows :—
In converting iron into steel by the process of cementation I employ
a reverberatory furnace, retort, or other suitable receptacle capable of
being as nearly as possible hermetically closed, and provided with a 1
valve to permit the escape of any gases generated during the process.
The furnace is also to be fitted with a fireproof lube or duct furnished
with stop-cocks or other suitable appliances at a certain distance apart,
the use of which will be presently described.
The bars or other forms of wrought iron are placed in the furnace, 1
which may resemble a baker's oven, the door of which after the bars
are inserted is to be thoroughly luted or otherwise secured to exclude
air; when at a sufficient heat (varying qualities of iron employed or of
steel to be made demanding different heats) the ascertained charge of
carbon as nearly as possible in a pure state is to be introduced to the
furnace, whilst the iron is still in the required condition to absorb it.
For this purpose the carbon is to be passed through the fireproof tubo
before named, the one stop-cock being closed before the other is opened to
exclude the air during the operation; as it enters the furnace the carbon
becomes vaporized, and in that state is speedily and equably absorbed by
the iron; and as the furnace and its appliances are constructed by
preference of materials having no affinity for carbon, the whole of the
carbon is absorbed by the iron with the exception of possibly some very
minute portion which may escape through the valve with the hydrogen
or other gases evolved during the operation. Any hydrocarbon or other
carbonaceous matter alone or in combination capable of this treatment
may be employed, but those which I prefor, as they contain very large
quantities of pure carbon, arc gas tar or an oil known under the names
of creosote oil, oil of coal tar or dead oil, and coal tar, spirit or mineral
naptha, the resultants of the distillation of coal gas tar.
In making cast steel the metal in as puro a stato as possible having
been melted in a refinery or other suitable furnace is for some qualities,

page_text: whilst in a molten state, for others at a lower heat, to be impregnated
with carbon in a similar manner.
The case hardening of wrought or malleable iron articles I effect by
the same process as that already described for making steel by cementa-
tion, only stopping short at any time of complete conversion, which can
be effected either by means of a lower heat or by shortening the time of
the operation.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Pinley Sharp in the Great Seal Patent
Office on the 5th August 1873.
-
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
PINLEY SHARP, of Birmingham, in the County of Warwick, Tar Distiller,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifth day of February, in the year
of our Lord One thousand eight hundred and seventy-three, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said James Pinley Sharp, Her special
license that I, the said James Pinley Sharp, my executors, adminis-
trators, and assigns, or such others as I, the said James Pinley Sharp,
my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain.
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF STEEL, AND IN CASE HARDENING OR
PARTIALLY CONVERTING IRON INTO STEEL," upon the condition (amongst
others) that I, the said James Pinley Sharp, my executors or adminis-
trators, by an instrument in writing under my, or their, or one of
their hands and scals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be
performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.

page_text: NOW KNOW YE, that I, the said James Pinley Sharp, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, that is to say :-
This Invention has for its object the production of steel with greater
accuracy and certainty as to quality than is attained by any of the
processes at present followed, so that an operator knowing the quality
of iron hic is employing and the description of steel ho desires to produce
may be enabled accurately to adjust the quantity of carbon by employing
such carbon in as nearly as possible its purest state and under conditions:
favourable to its regular and equable absorption by the iron at the
moment the latter has attained the degree of heat most favourable for
its conversion; and my Invention embraces improvements in making
steel either by cementation or by casting, and is as follows:-
In converting iron into steel by the process of cementation I employ
a reverberatory furnace, retort, or other suitable receptacle capable of
being as nearly as possible hermetically closed, and provided with a
valve to permit the escape of any gases generated during the process.
The furnace is also to be fitted with fireproof tubes or ducts furnished
with stop-cocks or other suitable appliances at certain distances apart,
the use of which will be presently described.
The bars or other forms of wrought iron are placed in the furnace,
which may resemble a baker's oven, the door of which after the bars aro
inserted is to be thoroughly luted or otherwise secured to exclude air;
when at a sufficient heat (varying qualities of iron employed or of steel
to be made demanding different heats) the ascertained charge of carbon
as nearly as possible in a pure state is to be introduced to the furnace,
whilst the iron is still in the required condition to absorb it. For this
purpose the carbon is to be passed through the fireproof tube before
named, the one stop-cock being closed before the other is opened to
exclude the air during the operation. As it enters the furnace the carbon
becomes vaporized, and in that state is speedily and equably absorbed by
the iron; and as the furnace and its appliances are constructed by
preference of materials having no affinity for carbon, the whole of the
carbon is absorbed by the iron with the exception possibly of some very
minute portion, which may escape through the valve with the hydrogen
or other gases evolved during the operation. Any hydrocarbon or other
carbonaceous matter alone or in combination capable of this treatment

page_text: may be employed, but those which I prefer, as they contain very large
quantities of pure carbon, aro gas tar or an oil known under the names
of creosote oil, oil of coal tar or dead oil, and coal tar, spirit or mineral
naptha, the resultants of the distillation of coal gas tar.
In making cast steel the metal in as pure a state as possible having
been melted in a refinery or other suitable furnace is for some qualities
whilst in a molten state, for others at a lower heat, to be impregnated
with carbon in a similar manner.
The case hardening of wrought or malleable iron articles I effect by
the same process as that already described for making steel by cementa-
tion, only stopping short at any time of complete conversion, which can
be effected either by means of a lower heat or by shortening the time of
the operation.
Having thus described the object and nature of my said Invention,
and the manner in which the same is to be carried into effect, I claim
without confining myself to these precise details, the several improve-
ments in the manufacture of steel, and in case hardening or partially
converting iron into steel, substantially in manner as herein more fully
set forth and specified.
In witness whereof, I, the said James Pinley Sharp, have here-
unto set my hand and seal, this Thirtieth day of July, in
the year of our Lord One thousand eight hundred and seventy-
threc.