IMPROVEMENTS IN FARD
Year: 1855

page_text: LETTERS PATENT to William Truran, of Marazion, in the County of
Cornwall, Civil Engineer, for the Invention of "IMPROVEMENTS IN
FARD
"
Sealed the 18th January 1856, and dated the 30th July 1855.
PROVISIONAL SPECIFICATION left by the said William Truran at the
Office of the Commissioners of Patents, with his Petition, on the 30th
July 1855.
I, WILLIAM TRURAN, of Marazion, in the County of Cornwall, Civil En-
gineer, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN SMELTING, AND IN APPARATUS TO BE USED THEREIN," to be as follows:-
In iny improved mode of smelting, I divide the internal bore of the blast
nozzle or nozzles in such a manner that it or they shall deliver a divided jet
or two or more jets of blast into the interior chamber through the same tuyere.
the pressure of the blast delivered by the respective jets being either alike or
dissimilar, as may be advisable, and of such form and relative proportions as
the peculiar circumstances of the furnace and materials consumed may require;
and I construct the throat or mouth of the interior chamber, through which
the decomposed blast escapes into the atmosphere, and of so much of the
interior chamber as lies above the boshes, of a breadth equal to or in excess
of the breadth of the chamber at the upper bosh line, and of an area in the
plan section equal to or in excess of the area at the upper bosh line.
The form of the jet and the intensity of the blast delivered by the respective
divisions of the divided nozzle pipe may be varied by substituting other nozzles

page_text: differently divided, and the general dimensions of the nozzle likewise may
be adapted to local circumstances; but I prefer forming the nozzle of two
cylindrico-conical cases of different sizes, the lesser being inside the larger, and
maintained in its position excentrically or concentrically, as may seem best, by
suitable connecting pins or pieces, care being taken that such connections do
not materially impede the delivery of the blast. When it is desired that the
blast issuing from the circular central orifice shall be of equal pressure and
intensity with that issuing from the annular orifice, the proportion of taper, if
any, in both inner and outer cases may be nearly similar.
In the construction of the blast furnace and nozzle pipe, or of so much as
differs from those ordinarily employed, I employ the metals and materials
heretofore employed for such purposes.
By means of the improvements herein described, I am able to smelt
iron ores with greater economy of fuel, blast, and other materials than here-
tofore, and can successfully smelt iron ores of every description with raw or
uncoked coal, which hitherto has been coked before use in the blast furnace,
and am enabled to produce iron of fine quality without passing the ore through
the preliminary operation of calcination, which has not heretofore been accom-
plished with the ores, known to geologists as the carbonates of the coal
formations, and to practical smelters as clay band and black band iron-
stones.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Truran in the Great Seal Patent Office on the
30th January 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
TRURAN, of Marazion, in the County of Cornwall, Civil Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirtieth day of July, in the year of our Lord One
thousand eight hundred and fifty-five, in the nineteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William Truran, Her special licence that I, the said William Truran, my
executors, administrators, and assigns, or such others as I, the said William
Truran, 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

page_text: Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
SMELTING, AND IN APPARATUS TO BE USED THEREIN," upon the condition (amongst
others) that I, the said William Truran, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands and seals,
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.
NOW KNOW YE, that I, the said William Truran, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:—
Heretofore in supplying furnaces of the kind known to metallurgists as
blast furnaces for the reduction of iron ores with the requisite blast or atmo-
spheric air under compression for maintaining active combustion of the fuel
contained therein, one or more cylindrical or cylindrico-conical blast pipes,
termed "nozzle pipes," are disposed around the hearth or lower portion of the
interior chamber of such furnace, from each of which nozzle there issues a
single undivided jet or stream of blast under a certain pressure or compression,
and passing through the tuyere for that purpose provided, enters the interior
chamber of the furnace, and eventually escapes at the top through that portion
of the chamber above the boshes known as the throat or filling mouth, which
is constructed of a diminished breadth, its diameter being such that the super-
ficial area on the plan section in all furnaces hitherto built is under the one-half
of the area of the diameter of the furnace at the upper bosh line.
In order that my Invention may be better understood, I have hereunto
annexed a Sheet of Drawings, with letters of reference thereon corresponding
to the letters herein; Figure 1 being a longitudinal section; and Figures 2
and 3, end views of the large and small ends of same; and Figures 4, 5, and 6,
vertical sections of existing blast furnaces, shewing the interior form of such,
more especially of that portion which lies above the bosh line A, A.
In my improved mode of smelting, divide the internal bore of the blast
nozzle or nozzles in such a manner that it or they shall deliver a divided jet
or two or more jets of blast into the interior chamber through the samo tuyre;
the pressure, temperature, and general qualities of the blast delivered by the
respective jets being either alike or dissimilar, as may be advisable, and of
such form and relative proportions as the peculiar circumstances of the furnace
and materials consumed may require; and I construct the throat or mouth of
the interior chamber, through which the decomposed blast escapes into the

page_text: atmosphere, and of so much of the interior chamber as lies above the boshes,
of a breadth equal to or in excess of the breadth of the chamber at the upper
bosh line, and of an area in the plan section equal to or in excess of the area
at the upper bosh line.
The form of the jet and the intensity of the blast delivered by the respective
divisions of the divided nozzle pipe may be varied by substituting other nozzles
differently divided, and the general dimensions of the nozzle likewise may be
adapted to local circumstances; but I prefer forming the nozzle of two cylin-
drico-conical cases of different sizes, the lesser being inside the larger, and
maintained in its position excentrically or concentrically, as may seem best, by
suitable connecting pins or pieces, care being taken that such connections do
not materially impede the delivery of the blast. When it is desired that the
blast issuing from the circular central orifice shall be of equal pressure and
intensity with that issuing from the annual orifice, the proportion of taper, if
any, in both inner and outer cases may be nearly similar. Figure 8 of accom-
panying Drawing is a longitudinal section of such nozzle pipe; and Figure 7,
a transverse section of same. When it is desired that the jet issuing from the
exterior annular orifice shall be of a different pressure to that issuing from the
central orifice, the nozzle may be made with a branch pipe for conveying blast
of the required pressure into the annular space between the two cases, as may
be seen by referring to Figure 9, which is a longitudinal section of such nozzle,
D being the branch pipe for supplying the annular jet; but I prefer varying,
that is, decreasing the pressure or intensity of the blast at the point of exit,
by diminishing the sectional area of that portion of the interior of the nozzle,
in such a manner as to cause a partial obstruction to the passage of the blast,
which results in the jet issuing with inferior velocity and intensity. When it
is desired that the blast delivered by the annular portion of the compound
nozzle be of an inferior intensity at the point of exit compared with the
intensity of that issuing from the central orifice, I reduce the area of the
annular passage at B, B, Figure 10, or at some other point in its length; but
when it is desired that the blast delivered by the central orifice shall possess
the lesser intensity, I reduce the area of the central orifice at c, c, Figure 11,
or some other point in its length sufficient to produce the desired effect.
The nature of my improvement, which bears on the escape from the furnace
-of-the-decomposed_blast, may be more particularly seen by referring to_the_
accompanying Sheet of Drawings, wherein Figures 12, 13, and 14 are vertical
sections of blast furnaces, shewing the enlargement of the interior chamber at
the top, as compared with the form of chamber heretofore adopted.
In the construction of the blast furnace and nozzle pipe, or of so much as

page_text: differs from those ordinarily employed, I employ the metals and materials
heretofore employed for such purposes.
By means of the improvements herein described, I am able to smelt iron
ores with greater economy of fuel blast and other materials than heretofore,
and can successfully smelt iron ores of every description with raw or uncoked
coal, which hitherto has been coked before use in the blast furnace, and am
enabled to produce iron of fine quality without passing the ore through the pre-
liminary operation of calcination, which has not heretofore been accomplished
with the ores known to geologists as the carbonates of the coal formations,
and to practical smelters as clay band and black band iron-stones.
Having now fully described and ascertained the nature of my Invention, I
wish it to be understood that I claim as my Invention,―
First, the nozzle pipe delivering through one tuyere two or more jets of
blast, whether the same be hot or cold, and irrespective of volume.
Secondly, the application to blast furnaces generally of such nozzle pipes
with the internal bore divided, as described.
Thirdly, the employment in smelting of nozzle pipes delivering two or more
jets of blasts of dissimilar intensity.
Fourthly, the employment of the divided bore nozzle pipe conjointly with
the peculiar form of chamber described.
Fifthly, the construction of the interior chamber of blast furnaces in the
manner described.
Sixthly, the employment of the peculiar form of chamber described con-
jointly with the use of raw ores for the production of superior iron, the said
ores heretofore having been calcined or subjected to heat before entering the
blast furnace.
Seventhly, the employment of the peculiar form of chamber described con-
jointly with the use in the raw or uncoked state of such coals as heretofore
have been coked or charred before entering the blast furnace.
In witness whereof, I, the said William Truran, have hereunto set my
hand and seal, this Thirtieth day of January, in the year of our
Lord One thousand eight hundred and fifty-six.
WILLIAM TRURAN, C. E. (L.
(L.B.)