IMPROVE- MENTS IN THE MANUFACTURE OF IRON AND STEEL, AND IN FURNACES TO BE USED IN SUCH MANUFACTURE
Year: 1869

page_text: LETTERS PATENT to Joseph Henderson, of Auchencairn, near Castle
Douglas, North Britain, Gentleman, for the Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF IRON AND STEEL, AND IN FURNACES TO BE
USED IN SUCH MANUFACTURE."
Sealed the 7th September 1869, and dated the 9th March 1869.
PROVISIONAL SPECIFICATION left by the said Joseph Henderson at
the Office of the Commissioners of Patents, with his Petition, on
the 9th March 1869.
I, JOSEPH HENDERSON, of Auchencairn, near Castle Douglas, North
Britain, Gentleman, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF IRON AND STEEL, AND IN FURNACES
TO BE USED IN SUCH MANUFACTURE," to be as follows:-
This Invention relates to improvements in the construction of blast
furnaces and puddling furnaces, which will enable me to manufacture
iron and steel with considerable economy, and carry on conveniently the
processes of puddling and steel melting in crucibles (for the manufacture
of best tool steel) at one and the same time.
The puddling furnace may be termed a double reverberatory furnace, as
the hearths, four in number, are arranged two in a line, and placed back

page_text: to back to receive their heat from one and the same fire chamber. In this
chamber I use waste or small coal as fuel, with a blast of air on each
side which consumes all cinder, and enables the heat to be kept up night
and day without any stoppage whatever from cleaning or renewing the
fire. Any number of hearths thus arranged may be placed side by side,
but I prefer to arrange them in groups of two for the purpose of welding
the blooms in the furnace clear of scale for the production of large
masses for armour, slab, girder, or rail direct, and thus save the cost of
piling. Each hearth I surround with air flucs, and I form also air flucs
beneath tho hearths, which are all regulated by inside and outside
dampers supplying the same from the external air, and allowing them to
discharge heated air into the furnace a little above the boshes of the
hearths as required. In the middle wall dividing the two lines of
hearths I form flues for discharging in a heated state air admitted to
the furnace through openings at the base of a common vertical shaft,
which serves to carry off the gases of combustion. In the bottom lining
of this shaft, just below the metal mantle plate carrying the top part of
said shaft from top of cast-iron pillars, I admit air which circulates along
each roof to the fire chamber for discharging in a heated state into the
rising gases, and there igniting them over the fire bridge, which effects
complete combustion and gives off any kind of flame required. In the
back of each bearth at a certain height I have a tap hole for running off
slag, which falls into trams. Air is allowed to pass over this slag along
the middle wall, and is discharged on to the deflected flame of the
fire-place.
The boshes are made to receive crucibles for melting the metal for
conversion into cast steel, and it is also intended to employ them for
receiving the ore which is ultimately to be fused and converted into
steel or puddled iron in the hearths. Above the hearths are fitted
tuyeres for blowing down highly-heated air on to the molten metal on the
hearths. The large doors of the furnace are provided with puddling
holes, which are closed air-tight as usual, and a communication under
the command of the puddler is made between the hearths to allow of
metal being run from one to the other. At the vertical shaft end of the
furnace an opening is made in communication with a blast furnace, from
which I take my supply of metal as it is run therefrom direct on to the
hearths of the puddling furnace, which I here purify by its own slag and
other fluxes. previously refined and prepared. The heat required for

page_text: operating upon this metal may also be employed to melt blistered steel
placed in crucibles on the boshes; but when I want to produce a good
tough quality of iron direct I sometimes take calcined ore which has
been crushed into small pieces and mix it with a suitable flux, and place
the same on the boshes, and so soon as the ore shows indications of
softening I rake it into the melted metal on the hearths, and smelt and
puddle upon the hearth. This melted metal I prefer to obtain from my
improved construction of blast furnace, which besides admitting of being
more cheaply built than ordinary blast furnaces, possesses a further
important recommendation.
In smelting furnaces as ordinarily constructed the height of fall of
the fuel through the licated gases causes a useless consumption of thic
fuel, which acts only beneficially when lying in contact with the ore and
while under the action of the blast. In order to avoid this waste I now
propose to construct blast or smelting furnaces with the roof of the
furnace resting on the boshes or inclined sides thereof, instead of as
heretofore running up the furnace a considerable height in a cylindrical
form, and then finishing with a taper top closed by the bell-mouth feeder.
The roof of my improved furnace I construct of iron girders crossing
each other and so arranged that they will form four nearly rectan
gular spaces circumscribed by the furnace wall. These spaces I severally
close at bottom with a pair of folding doors or valves opening inwards or
towards the interior of the furnace, and by a single door or valve opening
outwards. In the central division made by the girders I fit a tube with
a coned base for leading off the combustible gases from the furnace, and
the roof I complete by applying iron plates to the girders. The spaces
closed by the valves form hoppers which I use for containing the ore
mixed with a proper proportion of fuel and flux, and I charge the
furnace from these hoppers in succession, allowing the charge to fall on to
the conical bosh and distribute itself over the hearth. This arrangement
removes the necessity for the inverted cone distributor at present
employed, and as the height of the furnace is materially diminished the
fall of the charge will be through a proportionately reduced column of
flame and gas, and consequently the useless burning of the fuel in the
upper part of the furnace will be avoided.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Henderson in the Great Seal Patent Office
on the 9th September 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
HENDERSON, of Auchencairn, near Castle Douglas, North Britain,
Gentleman, send greeting.
WHEREAS Her most Excellent. Majesty Queen Victoria, by Her
Letters Patent, bearing date the Ninth day of March, in the year of our
Lord One thousand eight hundred and sixty-nine, in the thirty-second
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Joseph Henderson, Her special licence that I,
the said Joseph Henderson, my executors, administrators, and assigns,
or such others as I, the said Joseph Henderson, my executors, adminis-
trators, 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 MANU-
FACTURE OF IRON AND STEEL, AND IN FURNACES TO BE USED IN SUCH MANUFACTURE,"
upon the condition (amongst others) that I, the said Joseph Henderson,
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 Joseph Henderson, 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, reference being had to the Drawings
hereunto annexed, and to the letters and figures marked thereon (that is
to say) -
:-
This Invention relates to improvements in the construction of blast
furnaces and puddling furnaces, which will enable me to manufacture
iron and steel with considerable economy, and carry on conveniently
the processes of puddling and steel melting in crucibles (for the manu-
facture of best tool steel) at one and the same time.

page_text: The puddling furnace may be termed a double reverberatory furnace
as the hearths are arranged two deep, being placed back to back, so as
to receive their heat from one and the same fire chamber. In this
chamber I use waste or small coal as fuel, with a blast of air on each
side which consumes all cinder, and enables the heat to be kept up
night and day without any stoppage whatever from cleaning or renewing
the fire. Any number of hearths thus arranged may be placed side
by side, but I prefer to arrange them in groups of two for the purpose
of welding the blooms in the furnace clear of scale for the production
of large masses for armour, slab, girder, or rail direct, and thus save the
cost of piling.
In the accompanying Drawings Fig. 1., Shect I., shews my improved
puddling furnace in sectional plan; Fig. 2 is a longitudinal vertical
section of the same taken in the line 1, 2, of Fig. 1, and Fig. 3 is
a traverse section taken in the line 3, 4, of the same Figure.
A, A, are the outer walls of the furnace, and B is the chimney shaft
set at the back end thereof; C, C, are the fire chambers and grates,
and D, D, the puddling hearths. These hearths are composed of "ganister
or bulldog" or cast iron bottoms, and over them play the flames and
heated gases of the fire-places C; E are air passages formed in the side
and cross walls of the furnace and under the bottoms of the hearths.
These passages are supplied with air from openings at the rear end of the
furnace and are intended to heat the air in its course, so that it may be
discharged in a heated state into the furnace at the points E*, E*, and
caused to mingle with the flame and heated gases as they are deflected on
to the metal contained on the hearths; F, F, is an air passage formed in
the longitudinal dividing wall F¹, and serving to supply heated air to the
fire-places; G is a hollow curtain which forms the back of the upper
part of the fire chamber as the transverse wall or bridge in front of
the first puddling hearth forms the back of the lower part of the fire
chamber C. Each hollow curtain has an opening forwards for the
discharge of heated air on to the ascending flame as it leaves the fire
chamber, and it is connected with a horizontal air passage G' formed"
in the roof of the furnace and supplied with air from an annular channel
surrounding the base of the chimney shaft B and opening to the atmo-
sphere; H is an opening for admitting liquid metal from the blast
furnaces to the puddling furnace. Connected with this opening His
a channel II' which leads by gutters H2 in the sides of the central

page_text: wall F¹ to the puddling hearths. Fitted in the channel H' is a vertical
swinging door I which serves to direct the course of the metal either to
the right or the left-hand pair of puddling hearths, as desired. J, J, are
the puddling doors in the sides of the furnace, and K are charging doors
in line with the boshes through which the crucibles (when steel is
required to be melted) or roasted ore when that is required to be
added to the molten metal L on the hearths may be supplied to the
furnace; M, M, are the roof bridges for throwing down the flame and
heated gases, and causing the same to impinge upon the molten metal;
N, N, are the blast pipes and tuyeres. The tap holes (when required)
are situate at O; P are the puddling door levers; R is the chimney
stack damper, and S, S, indicate the situation of the steel crucibles
when they are employed in the furnace. The air flues surrounding.
the hearths are all regulated by inside and outside dampers, and although
supplied from the external air it will be readily understood that this
arrangement will allow of the. discharge of heated air into the furnace
a little above the boshes of the hearths as required. The air passage F
in the middle wall dividing the two lines of hearths receives its air
from an opening in the rear end of the furnace like the air passages E
(see Fig. 2). The air drawn into the bottom lining of the chimney
shaft B just below a metal mantle plate carrying the top part of said
shaft from top of cast-iron pillars circulates along passages G' in the
roof to the furnace for discharging in a heated state into the rising
gases, and there igniting them over the fire bridge, which effects complete
combustion and gives off any kind of flame required. The course of
the air and its discharge into the furnace will be readily traced by the
blue arrows. In the back of each licarth at a certain height, I have
a tap hole for running off slag which falls into trams. Air is allowed
to pass over this slag along the middle wall and is discharged on to
the deflected flame of the fire-place.
The boshes constructed as shewn are fitted to receive crucibles for
melting the metal for conversion into cast-steel, and thus utilizing the
waste heat of the puddling furnace. Or the boshes may be employed
for receiving the ore which is ultimately to be fused and converted
into, steel or puddled iron in the hearths. The tuyeres Nitted.above
the hearth are used to blow down highly heated air on to the molten
metal on the hearths; the doors J are provided with puddling, holes
which are closed air-tight as usual: Gates under the command of the

page_text: puddler are provided for opening and stopping communication between
the hearths and the gutters H. This arrangement allows the puddler`
at any time to fill all four hearths or any one he may desire, and that
without any interference with the working off of the other hearths.
From the foregoing explanation it will be understood that when the
opening H in the back end of the furnace is brought into communi-
cation with an adjacent blast furnace I can take my supply of metal
as it is run therefrom direct on to the hearths of the puddling furnace,
and purify it with its own slag and other fluxes previously refined:
and prepared. The course of the fluid metal is indicated by the red
arrows. The heat required for operating upon the molten metal will
also serve as already indicated to melt blistered steel, and to that end
I place the blistered steel in crucibles on the boshes as at S, S. When
I want to produce a good tough quality of iron direct I sometimes take
calcined ore which has been crushed into small pieces and mix it with
a suitable flux and place the same on the boshes in the place of the
crucibles, and so soon as the ore shews indications of softening I rake`
it into the melted metal on the hearths and smelt and puddle upon the.
hearth. This melted metal I prefer to obtain from improved con-
struction of blast furnace which besides admitting of being more.
chicaply built than ordinary blast furnaces possesses a further important
recommendation. This blast furnace is shewn in vertical section at
Fig. 4, Sheet II.
I have found that in smelting furnaces as ordinarily constructed the.
height of fall of the fuel through the heated gases causes a useless
consumption of the fuel which acts only beneficially when lying in
contact with the ore and while under the action of the blast. In order
to avoid this waste I adopt the construction of blast or smelting furnace
shown at Fig. 4 wherein it will be seen that the roof of the furnace
rests on the boshes or inclined sides thereof instead of as heretofore
the furnace being run up a considerable height in a cylindrical form,
and then finishing with a taper top closed by a bell mouth feeder. The
roof of my improved furnace I construct of iron girders A, A, crossing
cach other, and so arranged that they will form four nearly rectangular
spaces circumscribed by the furnace wall B. These spaces I severally
close at bottom with a pair of folding doors or valves C, C, opening
inwards or towards the interior of the furnace and by a single door
or valve D opening outwards. In the central division made by the

page_text: girders I fit a tube E with a coned base for leading off the combustible
gases from the furnace, and the roof. I complete by applying iron
plates F, F, to the girders. The spaces closed by the valves form
hoppers G which I use for containing the ore mixed with a proper
proportion of fuel and flux, and I charge the furnace from these hoppers
in succession, allowing the charge to fall on to the conical bosh and
distribute itself over the hearth. This arrangement removes the
necessity for the inverted cone distributor commonly employed, and
as the height of the furnace is materially diminished the fall of the
charge will be through a proportionately reduced column of flame and
gas, and consequently the useless burning of the fuel in the upper part
of the furnace will be avoided. The constructive cost of the furnace
will obviously from its diminished height be materially lessened.
Having now set forth the nature of my Invention of "Improvements
in the Manufacture of Iron and Steel, and in Furnaces to be used in
such Manufacture," and explained the manner of carrying the same
into effect, I wish it to be understood that under the above in part
recited Letters Patent I claim,-
First. Constructing puddling furnaces as above described with
reference to Sheet I. of the Drawings, and also the utilization of the
boshes in the manner and for the purposes above explained.
Secondly. Constructing blast furnaces as above described with
reference to Sheet II. of the Drawings, whereby among other economical
advantages the profitable consumption of the fuel supplied thereto
will be greatly increased.
In witness whereof, I, the said Joseph Henderson, have hereunto
set my hand and seal, the Seventh day of September, in the
year of our Lord One thousand eight hundred and sixty-nine.