IMPROVEMENTS IN THE CONSTRUCTION OF BLAST FURNACES
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES YATES,
of Mashorough, in the Parish of Rotherham, York, Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her Royal
Letters Patent under the Great Seal of the United Kingdom of Great Britain
and Ireland, bearing date at Westminster, the Fourteenth day of December,
One thousand eight hundred and forty-six, in the tenth year of Her reign, did,
for Herself, Her heirs and successors, give and grant unto me, the said James
Yates, my exors, adñiors, and assigns, Her especial licence, full power, sole
privilege and authority, that I, the said James Yates, my exors, admors, and
assigns, or such others as I, the said James Yates, my exors, admors, or
assigns, should at any time agree with, and no others, from time to time and
at all times thereafter during the term of years therein expressed, should
and lawfully might make, use, exercise, and vend, within England, Wales, and
the Town of Berwick-upon-Tweed, and in all Her Majesty's Colonies and
Plantations abroad, and also in the Islands of Jersey, Guernsey, Aldeney,
Sark, and Man, my Invention of "IMPROVEMENTS IN THE CONSTRUCTION OF BLAST
FURNACES;" in which said Letters Patent is contained a proviso that I, the said
James Yates, shall cause a particular description of the nature of my said
Invention, and in what manner the same is to be performed, by an instrument
in writing under my hand and seal, to be inrolled in Her Majesty's High
Court of Chancery within six calendar months next and immediately after the
date of the said in part recited Letters Patent, as in and by the same, reference
being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said James
Yates, do hereby declare that the nature of my said Invention, and the manner
in which the same is to be performed, are fully described and ascertained in
and by the following statement thereof, reference being had to the Drawings
hereunto annexed, and fo the figures and letters marked thereon, that is to
say:
In constructing blast furnaces it has heretofore been usual so to arrange
them that the charge shall remain in the furnace so long a time as possible
compatible with the quantity of iron required to be made, it being considered
that a beneficial effect is obtained by what is called the cementing process,
which results from the iron stone or ore being, together with the fuel, subjected
to heat for a length of time; and it is well known that according to the present
constructions of blast furnaces, owing to their dimensions when compared with
the product of iron, that each part of the charge must remain in the furnace
for many days. Now I am of opinion that the construction of furnaces to work
according to this principle of retaining the charge a long time in the furnace is
erroneous, and the first part of my Invention is grounded on a principle the
reverse of that which has heretofore prevailed; for I believe that a more advan-
tageous result may be obtained in smelting iron stone mines or ore in the manu-
facture of iron, by reducing the height of the furnace, and by so arching in and
arranging the upper part of the furnace as to give an increased surface upon the
materials within, to produce a reverberation of the heat above the charge, and so
that the charge may at once enter into a more highly heated place than has hereto-
fore been considered desirable. In charging ordinary blast furnaces, it has hereto-
fore been usual to charge them and keep them charged up to the tunnel head,
and the heated vapours or products have heretofore immediately passed off at
the tunnel head on escaping the charge. In constructing and working blast
furnaces according to this part of my Invention, the top of the charge is con-
siderably below the tunnel bead at which the unconsumed vapours or products
pass off, and the flame and ignited products reverberate against the arched
upper part of the furnace, and the heat is thrown back on the upper or fresh
part of the charge in such manner as to cause it to be highly heated, the
vapours or unconsumed products passing away at or near the centre of the arch;
and the charge is so introduced at the sides of the furnace that the charge is
hollow in the centre, by which the resistance to the passage of the blast is less
in the centre than at the sides. By these arrangements, together with using
more numerous twyeres, and these more equally, divided, I am enabled to
obtain a large product of iron of the best quality from a comparatively small
furnace, the charge not remaining in the furnace more than a few hours (say

page_text: under twenty-four hours); and I have found that in using a blast furnace,
such as is shown at Figure 4, which is under twenty feet high from the twyere
pipes to the surface of the burden or materials, and of the increasing diameter
upwards from the hearth, as marked in the Drawing, will produce one hundred
and ten tons per week from Derbyshire ore, which is lean compared with other
ores in England, Wales, and Scotland, using six twyeres of 14 inches diameter,
and hot blast (under 1½ lbs. on the square inch), which I prefer, but do not
confine myself thereto. This part of my Invention is most advantageous when
building new furnaces; but old blast furnaces may be altered and rendered more
advantageous according to my Invention.
And in order that this part of my improvements may be most fully
understood, and readily carried into effect, I will proceed to describe the
Drawing Number 1, where old furnaces, suitably altered, are shewn, as
well as several new constructions of furnaces; all, however, arranged ac-
cording to the principles above stated. The ordinary. construction of
blast furnaces consists of two cones meeting at the boshes; but of lato
years in some cases the upper parts of the furnaces have been made moro
approaching a cylindrical form; their construction and relative dimensions,
however, vary very much; but whatever be the construction of a blast furnace,
if it is to be altered according to my Invention, I apply a ceiling or dome,
or partial dome or ceiling, over the upper or in some other part of the shaft,
and make such arrangements in respect to the feed aperture or apertures as
will best secure an uniform surface around the sides of the materials in the
furnace, and a sufficient and uniform space between the upper surface
of the burden or materials in the furnace and the dome or ceiling, as to allow
a free escape of the unconsumed gases through the burden or materials, and
for the flame to reverberate and deflect upon the surface of the burden or
materials, but at the same time to confine the caloric as much as possible
within the upper chamber, as shewn in Figure 2, and herein-after described.
By the application of a dome or ceiling to the upper or in some other part of
the furnace, with the arrangement of feed apertures or aperture, so as to leave
sufficient space between the upper surface of the burden or materials, as before
described, the caloric, which in ordinary blast furnaces freely escapes, is
arrested by the dome or ceiling, deflected and radiated upon the burden in the
upper part of the furnace, which being comparatively cool, a great portion
of the caloric thus radiated and deflected is absorbed, thus effecting a saving
in time and an economy in fuel; it also obviates the necessity of so high a
furnace in proportion to its capacity, as the application of the spare caloric
(which in ordinary furnaces freely escapes) prepares the burden to a greater

page_text: extent for smelting, and being nearer the melting zone (the lower part of the
furnace) the materials are sooner brought into a state of fusion than in the
ordinary blast furnace, thus effecting a great saving in the consumption
of fuel, in addition to the saving in the first cost of constructing a furnace and
the saving of engine power, as the reduced height and increased upper surface
of the burden through which the blast circulates renders a less pressure of blast
necessary, and also saves power in raising the burden to the feeding apertures.
DESCRIPTION OF THE DRAWING NUMBER 1.
Figure 1 represents what is considered a good blast furnace, such as is now
in very general use, from the hearth a, a, to the landing E, E; a, a, to b, b,
represents the hearth; b, b, to c, c, the boshes; c, c, to d, the shaft; H, H, H, H,
the lining of fire-brick or fire-stone; D, D, D, D, the large mass of stone or
brick work forming the outer case. Figure 1 shows the plan or horizontal
section across from I to J, in Figure 1; a, the hearth; f.f.f, the tuyero holes;
G, G, G, the tuyere houses; H, H, H, H, the lining; D, D, D, D, the masonry
of outer case; M, the tapping house; N, the tapping hole or dam. Figure 1"
shows the plan or section from E to E, Figure 1, the same letters referring to
the same parts in both. This furnace is upwards of fifty feet high, from the
hearth a, a, to the landing and feed holes F. The hearth, a to a, is four feet
diameter; the top of boshes C, C, twelve feet diameter; the top of shaft d
seven feet diameter, tapering regularly downwards from d to C, C, the top d
being quite open. The tuyere holes f,f,f, have sometimes one tuyere pipe and
sometimes two in cach, but in consequence of their being only three holes, and
they being narrow, it leaves a large space between onc tuyere or one set of
tuyers and another; thus causing irregularity in the distribution of the blast
throughout the interior of the furnace.
Figure 2 represents a furnace, as before described in respect to Figures 1
and 14, with a reverberatory dome or ceiling applied, which I prefer to be of
fire-brick B; the funnel dropping so far below the dome as to prevent the
furnace being filled, and as to give a wider surface upon the materials,
and sufficient space for reverberation and deflection; e, e, the dampers to regu-
late the opening to such size as to allow the unconsumed gases to escape, and
at the same time to retain caloric, and so that the flame and heat within the
oven or chamber A, A, will be reverated on to the charge below; m, m, m,
shews the upper surface of the materials as it ought to be kept; E, E, the
landing. Figure 2 also represents the furnace, as before described, with the
improved top applied in the shaft at a distance from, instead of being
at the extreme top, as before described; K*, K, the partial dome or ceiling;

page_text: B³, the aperture through which the unconsumed gases escape; g*, g*, the feed
holes in the sides, below the under side of the dome, to secure in feeding the
furnace a large area or surface of material, and sufficient space for reverbera-
tion and deflection, within the chamber or oven A; ex, ex, the regulating
dampers; h, h, the doors to close the feed holes ; m, m, m, the surface of the
materials within the chamber A*, and Ex, Ex, the landing; this lower arrange-
ment I prefer, as more nearly approaching the construction according to which
I build new blast furnaces. Figure 2 B shews the top plan or horizontal
section across E to E, Figure 2.
'
Figure 3 represents a furnace upon the old or present construction as
before described, with the old tapered shaft removed and a more parallel one
applied, with the improved top or dome, as before described, and placed over
it, the same letters referring to the same parts. The red ink marks X, X,
shew a further improvement, by the hearth being much wider and the boshes
more perpendicular; the red ink marks y, y, shew the hearth wider than at
C, C, thus doing away with the usual taper of the boshes; Z, Z, Z, a small
chimney to protect the men from being burned. Figure 3 B shews top plan
or horizontal section across E to F, Figure 3.
Figure 4 represents a new furnace on the improved plan, with the shaft as
in Figure 1, c, c, to d of the present old furnace dispensed with, or nearly so, the
dome being thrown immediately or nearly over the top of the boshes; a, a, to
b, b, represents the hearth; b, b, to c, c, the boshes; A, the oven or chamber;
H, H, H, H, the lining of fire-brick or fire-stone; D, D, D, D, the outer case;
K, K, the dome or ceiling, or partial dome or ceiling; B, the aperture for the
escape of the gases; e, e, sliding dampers to adjust the size of aperture; g. 9,
the feed holes at the sides of the dome, below the centre, to prevent the furnace
being filled above the line m, m, m, which line is the surface of the materials
to give spaces for the gases to rise freely, and for the flame to be reverberated
or deflected upon the surface of the materials; h, h, the doors to close the feed
holes to keep in the heat; Z, Z, Z, the small chimney to carry the flame, gases,
&c. away from the men; E, E, the landing. Figure 4 shews the plan or
horizontal section across from I to J, Figure 4; a, the hearth; f,ff.ƒ‚, ƒ‚ ƒ›
the tuyere holes; G, G, G, G, G, G, the tuyere houses; in each case the
tuyere has a separate house, so that the tuyere houses are made more numerous
according to my Invention than when according to former constructions of
blast furnaces; H, H, H, H, H, H, H, the lining; 1, D, D, D, D, D, D, the
outer case; M, the tapping house; N, the tapping hole or dam. Figure 4 B
represents a mode of feeding thro' one aperture in the crown of the dome or
ceiling; fis a box in which the materials are conveyed to the crown; s is a

page_text: hanging conical bottom which lets down by a catch; the charge of materials
then drops upon the hanging cone a, a, which, being over-balanced, allows the
materials to fall in a sloping direction towards the sides of the furnace;
the dome then rises by the balance-weight g, and fills up the large aperture d, d,
there being a small apeture 6 in the top of the cone a, a, regulated to such
a size as may be required for the unconsumed gases to pass off the funnel or
projections y, y, dipping so far below the dome as to secure the required space
for reverberations, &c., giving similar results to those given by feeding at the
sides.
Figure 5 represents what I consider the still more improved blast furnace
than that at Figure 4; the hearth a, a, which is made considerably wider,
approximating nearer to the width at C, C.
Figure 6 represents the new improved furnace with the improved top,
similar to that described in Figure 4, excepting that the feed holes are nearer
the sides, for the purpose of keeping up the fuel at the sides more fully, and
insuring the hollow surface of the materials. This furnace is shewn to be wider
at b, b, than at C, C; the hearth tapering from below the tuyere b, b, to a, a,
and having a greater number of twyer houses and tuyeres.
a cross section of Figure 6, from I to J.
Figure 6 A shews
Figures 7, 7 A, and 7 B represent another arrangement of my new con-
struction of blast furnace, with a series of openings or tuyere holes around
the furnace f. ff. f. f, with boxes and ventilator doors to regulate the
draught, and with bars or gratings to keep in the material, the sizes
of the openings of such capacity as to allow sufficient air to pass through
into the furnace as may be required; the dotted lines O shew a high
chimney to the furnace to increase the draught; L, the flue to convey the
gases, air, and flame into a separate chimney, Figure 8, where it may be
required, instead of the chimney at 0; this chimney, by being made of suffi-
cient capacity, may be made available for several furnaces; V, a damper, to be
used instead of c, c, when desirable. I would state that I do not clain the use
of a chimney to obtain the desired draught of air, in place of a blast of air,
that having before been attempted; and I have only shown the arrangement
of my improved construction of blast furnace when using a chimney.
Another part of my Invention consists of improvements in the twyers of blast
furnaces. Figure 9 represents an improved twyere box and pipe, by the use of
which the blast passing into the furnace prevents the pipes from melting, and
supersedes the use of the twyere pipes, which have water circulating within
to prevent them melting; g, the lower chamber of the twyere box, divided from
the upper c by the partition d, into which the air is first blown through the

page_text: opening a; it then passes over the outer surface of the twyere pipe b, b, into
the upper chamber c, then through the opening f in the upper part of the
twyere pipe b, b, and out of the nozzle H; the twyere pipe 6, 6, may either
be cast of a piece with the box, or it may be cast separately, and screwed into
the box by screws or otherwise. Figure 9 is the end view of Figure 9, or
vertical section across from I to J.
I will now describe another part of my Invention. My improvement in con-
structing blast furnaces also consists of combining with blast furnaces cortain
apparatus to produce greater uniformity of pressure of the blast than has hitherto
been produced by reciprocating engines and cylinders, and to accomplish which I
use two or more reciprocating steam engines with blowing cylinders, but without
fly-wheel or beam, and with valves and valve gearing so arranged that one engine
when in motion works the valves of the other when at rest, or when its piston
is up to the end, thus causing it to make its return. The steam being kept up
to an uniform pressure upon the steam piston, gives uniform pressure upon
the blowing piston, and there being no fly-wheel or beam to interfere with the
motion of the pistons, they increase or decrease in speed according to the
quantity of air passing away through the twyeres, maintaining at the same time
uniformity of pressure in the blast pipes. To shew this more clearly I refer
to Drawing No. 2.
Figure 1 is a vertical section of one of a pair of engines working together:
A, the steam cylinder, with its piston a, and valves b, c, and valve rod d; B is
the blowing cylinder, with its piston h; this piston has cushions or buffers (or
they may be fixed upon the cylinder ends), with air-cells to give elasticity
when the piston is forced up to the cylinder, and to prevent injury by the
concussion; J is the piston rod or barrel, of such dimensions as to equalize
its arca with the area of the steam piston rod in proportion to their respective
pressures of air on the one and steam on the other, as also to give steadiness to
the motion of the piston; K, K, are the inlet valves, and L, L, are the two
outlet valves; M, the pipe to convey the air to the connecting pipe O.
Figures 2 and 3 show the horizontal sections of a pair of engines and blow-
ing cylinders and pumps, with plan of gearing to work the valves.
and at
To explain the mode of working:-The piston, Figure 2, is now up
rest; the piston a, Figure 3, moving its slide axle e, having carried the arm f
with its finger g at the opposite end of the shaft m, to the position shown, (after
the slide axle c has passed the end of the arm f, the arm f drops, there being
space left between the tappets i, i, so that the axle e on its return will catch
hold of the arm f on the opposite side,) and which finger, pushing the tappet

page_text: pin i, has closed the valve c, and opened 6 to the steam way; thus the piston a,
Figure 2, gets into motion, whilst the piston a, Figure 3, is still moving on to
the end; the arm S is then carried by the slide axle t, Figure 2, moving
by, the finger and the tappet p the valves of the engine, Figure 3, and thus
in sucession: V, V, V, V, are slides to work in guides to steady the piston
rods; W, W, are pumps worked by the slide axles e and t. By adding the
following parts shewn in dotted lines, viz., three arms p, p, p, Figures 1 and 2,
with connecting rod k and over-balance weight y to each engine, each engine
will work its own valves whilst the other engine is standing for repairs, packing,
&c. It will be seen by the above explanations and references to Drawings,
that by keeping the steam at one regular pressure per square inch upon the
steam pistons in motion, there will be as regular a resistance upon the air
piston, with pressure proportionate to their respective areas, that by keeping
one in motion whilst the other is making its return, and there being no fly-
wheel or beam to check or give impetus to the pistons, they are at liberty
to move at whatever speed may be required within their capacity to keep up
the supply to the twyere or exit pipes, the steam acting both as the moving
force and regulator.
I will now describe another part of my Invention, which has for its object the
regulating the blast to blast furnaces. Figure 4, Drawing No. 3, represents an
improved air regulator, which I use in connection with blast furnaces and blowing
cylinders, as at present constructed, to give greater uniformity of pressure of blast.
A is a flexible cylinder secured to the stationary end b, b; c, c, the moveable end or
piston guided by the rods d, d, any number of which may be used; B, the steam
cylinder, open to the atmosphere at the end e, and the other end et is connected
by the pipe f to the steam boilers; g, the piston; h, the piston rod, connected
with the moveable end of air cylinder c, c; i, the large air pipe which connects
the interior of the cylinder or regulator A with the blowing cylinder or
cylinders, by which it will be seen that the blowing cylinder and the regulator A
are connected by the pipe i, and the steam boiler and steam cylinder B are
connected by the pipe f, the areas of their respective pistons being propor-
tioned to the pressure of steam kept up in the boilers and the pressure of blast
required, the irregularities in the reciprocating blowing apparatus as at present
constructed will be blanced or regulated. I use in some cases, instead of the
steam cylinder B, a series of springs so adjusted as to move and give the
required pressure to the moveable end or piston c, c, as shown by m, but I do
not confine myself to the particular kind of spring there shown. I also use in
some cases, instead of the flexible cylinder A, a cylinder of metal or wood,

page_text: with internal piston, moved and regulated by steam or springs, as above
described. I am aware that cylinders have been used as regulators, but these
have had pistons weighted by solid substances to give the necessary pressure
of blast; and these solid pistons being moved by the air forced into their
cylinders with all the irregularities attendant upon the blowing apparatus, the
air being very elastic gives in some parts of the motion of the piston great
impetus, which rebounds and causes great vibration, and consequently irregu-
larity of pressure. Now by my improvements these objections are wholly, or in
a great measure, removed. The novelty of this apparatus consists of the use
of steam or springs for regulating the pressure of air from the blowing
machinery.
I will now describe another part of my Invention, which has for its object
the producing blast to a blast furnace by means of two or more fans placed on
the same axis, so that the air put in motion by one fan may be driven into the
case of the second fan, in case only two fans are used, and from that fan into
the pipe leading to the twyeres of a blast furnace; and I prefer that the pair or
other number of fans should be driven by a rotatory steam engine, by which
arrangement only one shaft or axis will be used for the engine and fans. In
the case of more than a pair of fans being used, then the product of the first
will be driven into the second, and the product of the second into the third,
and so on, and then to the furnace. I would remark that it is not new to
cause the air put in motion by one fan to pass into the case of another fan;
I do not, therefore, claim the same; this part of my Invention consisting
of placing the two or more fans on the same shaft or axis, and giving motion
thereto by a rotatory steam engine upon the same shaft.
Having thus described the nature of my Invention, and the manner in
which the same is to be performed, I would have have it understood that
I do not confine myself to the details shown and described, so long as
the peculiar character of either part of my Invention be retained. But what I
claim is,―
First, the arranging and constructing blast furnaces as herein described.
Secondly, I claim the mode of constructing twyeres so as to keep them cool
by the passage of air, as herein described.
Thirdly, I claim the mode of arranging and combining blowing cylinders
with steam engines, whereby the pressure of air is kept uniform, as above
explained.
Fourthly, I claim the regulating of the blast to blast furnaces by the pressure
of steam and springs.