Year: 1886

page_text: I, EDWARD WALSH, Jr., of 417 Olive Street in the city of St. Louis, State of
Missouri, United States of America, Glass Manufacturer, do hereby declare the
nature of this invention and in what mauner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
My invention relates to important modifications in the internal form, and in the
structural arrangement of blast furnaces which may be said to consist generally of
cylinder for hearth, an inverted truncated cone for bosh and a truncated cone for
shaft. Owing to the internal configuration and arrangement of these parts, as
heretofore adopted, it is found that in the descent of the fuel, layers and ore fluxes,
at that portion of the furnace where they are in a semi-molten or viscid state, their
tendency is to adhere to the boshes and furnace walls; and to this adhesion is to
be attributed most of the evils and irregularities incidental to the best designed
blast furnaces of the day, viz: Rapid deterioration of the Hearth Lining, high
silicon, small yield of a poor quality of white iron, chilling, jumping and scaffolding,
to remove which recourse has been had to the percussive drill, overhead tuyere,
cannon, coal oil, gunpowder and dynamite.
My invention has for its objects: To prevent the adhesion of slag or semi-molten
metal on the boshes and furnace walls, so as to insure an uninterrupted flow of the
materials and a larger output of metal from the furnace and to regulate the quality
and quantity of the product at will; to minimize the tendency of the walls to
bulge or give outwardly; to provide means of cooling the furnace externally, and
to repair the same without disturbing the furnace shaft, if desired whilst the
furnace is in operation.
In determining the relative dimensions of a furnace especially as to locating the
top of the bosh within the zone of fusion, the questions as to the capacity of this
zone of fusion must be determined by the density of the fuel, the temperature,
pressure and volume of the blast, and the natures of the ores and fluxes to be
employed. Thus it is determined that hard driving with increased volume of blast
at a lower temperature when treating refractory ores will produce a larger zone of
fusion, whereas, slow driving, high temperature of the blast less refractory ores,
and less dense fuel produce a smaller zone of fusion. The particular construction
illustrated in the drawing accompanying this specification is for the treatment of

page_text: very refractory hematite or magnetic ores with a dense coke employing the
temperature of the blast about eight hundred F., at a pressure of about four
pounds per inch and in volume of about sixteen thousand cubic feet per minute.
With a tuyere circle of ten feet in diameter, when the furnace is working under
the above named conditions, the zone of complete fusion extends upwards about
eight feet, the inclination of the bosh being about three inches foot.
per
My invention consists, firstly in placing the entire bosh and widest diameter
thereof well down within the zone of complete fusion and thence rapidly inclining
the walls of the furnace upwards to a certain height so as to overhang the bosh,
the furnace shaft being continued from this part with a gradual inclination
sufficient to allow of the easy descent of the materials to be acted upon into the
furnace without disturbing the disposition in which such materials are charged.
And secondly, in laying the joints of the brickwork composing the furnace proper
and hearth at an inclination downwards and inwards towards the centre of the
furnace;
and thirdly in surrounding the furnace proper externally with a double
row of columns, one above the other, for carrying the furnace shaft independently
of the lower portions, which are rapidly destroyed.
The accompanying drawing, represents a vertical section of my improved blast
furnace.
A represents the furnace proper, and B the furnace shaft, C is the bosh which is
brought down well within the zone of complete fusion and considerably lower than
in the ordinary blast furnace. From the bosh C the walls D of the furnace A are
tapered rapidly upwards and inwards in the form of a truncated cone so as to
overhang the besh C until they reach a portion or zone E of the furnace A where
the materials being acted upon are in a more or less solid condition. By this
particular location of the bosh C and overhanging form of the furnace walls D
between the bosh C and zone E the current of air from the tuyeres is more
perfectly disseminated throughout the outer portions of the materials in the
furnace than with ordinary wide boshes and any adhesion of slag or semi-molten
materials around the bosh C is prevented partly by the intense heat thereat and
partly by the reflex and delivery from the overhanging walls D of the furnace A.
Similarly also any temporary adhesion of semi-molten materials round said walls is
prevented.
From the line or zone E the furnace shaft B tapers or diminishes gradually
upwards with just sufficient inclination to allow of the easy descent of the solid
contents of the furnace without disturbing or mixing the materials as they are
relatively disposed and charged from the hopper F into the furnace.
In constructing the furnace A the bricks composing the walls D are laid with
their joints inclined from the outside downwards towards the centre of the furnace
as shown, by which arrangement the weight of the. bricks will gravitate inwards
and pressing upon one another will close or consolidate the structure, thereby
lessening the tendency of the walls D to bulge og spread and also preventing the
molten metal from escaping through the joints of the brickwork.
The joints of the bricks composing the hearth G are also inclined inwardly and
obliquely towards the centre of the furnace so as to form a firm resisting base.
To obviate the difficulty and inconvenience hitherto experienced in obtaining
access to and repairing the furnace proper of a blast furnace without removing or
deranging a considerable extent of the brickwork I support the shaft B of the
furnace on a double row of columns H H placed one above the other at suitable
distances apart around the outside of the furnace A. By this means the furnace A
is rendered a separate construction from the shaft B, and can be easily got at for
repairs or removal without disturbing the shaft B. Such arrangement also allows
of a lighter construction of the furnace A and thereby facilitates the cooling of the
brickwork by admitting of the circulation of air around the outside of the com-
paratively thin walls D of the furnace A.
The above described system of supporting the furnace shaft B on columns H H
separately from, but combined with the furnace A and the mode of arranging the

page_text: bricks in the construction of the latter may also be applied to any other descrip-
tion of blast furnace.
II are the tuyeres, J the blast pipe, and K the water jacket which, with the
remaining parts shown on the drawings or appertaining to furnace are similar to
those used in ordinary blast furnaces.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
1. A blast furnace in which the bosh C is located well down within the zone of
fusion instead of at an upper and colder portion thereof, or at a portion too far
removed horizontally from the heating influences of the ascending gases as hitherto
the case, substantially as shown and for the purpose specified.
2. The combination of the bosh C, with the rapidly tapering overhanging
walls D between the bosh C and line or zone E of the furnace A with furnace
shaft B having its walls or sides diminishing upwards with easy inclination,
substantially as described and for the purposes specified.
3. A blast furnace in which the bricks composing the walls of the furnace are
laid at an inclination towards the centre of the furnace, substantially as described
and for the purpose specified.
4. The double row of columns H H¹ in combination with the furnace shaft B
formed as described, substantially as described and for the purpose specified.
5. The double row of columns H H supporting the furnace shaft B in combina-
tion with the furnace A formed as described, substantially as and for the purpose
described.
Dated this 30th dox of Santambon 10UR