IMPROVEMENTS IN FURNACES EMPLOYED IN THE MANUFACTURE OF STEEL AND OTHER METALS OR MINERALS
Year: 1880

page_text: LETTERS PATENT to Allan Carswell Wylie and Thomas Lockerbie, of Cannon
Street, in the City of London, Engineers, for an Invention of "IMPROVEMENTS
IN FURNACES EMPLOYED IN THE MANUFACTURE OF STEEL AND OTHER METALS
OR MINERALS."
PROVISIONAL SPECIFICATION left by the said Allan Carswell Wylie and
Thomas Lockerbie at the Office of the Commissioners of Patents on the
24th December 1880.
ALLAN CARSWELL WYLIE and THOMAS LOCKERBIE, of Cannon Street, in the
City of London, Engineers. "IMPROVEMENTS IN FURNACES EMPLOYED IN THE
MANUFACTURE OF STEEL AND OTHER METALS OR MINERALS."
Our Invention relates to the better and more economical construction of
regenerative furnaces and hearths for the manufacture of steel or other metals
or minerals, whereby a more direct impingement of the hot gases upon the liquid
metal, a deflecting furnace roof independent of the ports, a convenient form of
cinder trap, an improved reversing valve, and a useful recess below the hearth are
obtained.
We so construct our furnace that the whole of the side flues for admission of the
currents of air and gas upon the surface of the molten metal are built upon the
main substructure of the furnace, and entirely independent of the deflecting furnace
roof. The entering faces of the flue towards the furnace are made in a turned
arch concave towards the hearth, and which may be made to overhang the hearth
at a considerable angle.
The arches are fixed securely in this overhanging position by strong wrought
iron stays or ties attached to the body of the furnace, so that when the deflecting
furnace roof is built in between the flue faces, the latter approach closely the sides
of the roof, but do not in any way rest upon it, nor are they dependent upon the
stability of the roof for support.
In case then of collapse of the roof, which is of small dimensions, the flue faces
and flues remain entire and firm, and the furnace can be easily and economically
renewed.

page_text: Owing to the overhang thus given to the furnace faces of gas and air flues these
latter can be conveniently and safely set out to a considerable angle of impinge-
ment upon the surface of the metal bath, even to as great an angle as 45° if
desired.
We have also so improved the substructure of our furnace that we can bring the
regenerator directly under the escaping current of hot gases from the furnace
without weakening the arched substructure, instead of through ports formed
in the keying of the arches supporting a principal part of the furnace as used
heretofore.
We also form convenient cinder traps in the floor of the gas exit flues close to
the furnace, so that the bottom of the pockets is on the working floor level, and
the cinder may be conveniently extracted at that level.
We construct our hearth so that it is supported on girders over an open area of
considerable depth in the substructure of the furnace which communicates around
the sides of the furnace bridges with ventilation exits into the open air. This area
or recess underneath the hearth is thus exceedingly useful both to keep the underside
of the hearth as cool as possible, and to facilitate access for repairs.
We also apply an improved form of valve for reversing the action of the gases
through the regenerator. The valve may be of the ordinary D shape travelling
over 3 ports, but instead of a sliding motion upon the port faces we move the valve
by a rocking lever from beneath, which thus lifts the valve slightly from one seat
and drops it rapidly upon the other. This motion is more easily effected then a
slide when the seats are gummy and sticky.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Allan Carswell Wylie and Thomas Lockerbie in the Great Seal Patent
Office on the 23rd June 1881.
ALLAN CARSWELL WYLIE and THOMAS LOCKERBIE, of Cannon Street, in the
City of London, Engineers. "IMPROVEMENTS IN FURNACES EMPLOYED IN THE
MANUFACTURE OF STEEL AND OTHER METALS OR MINERALS."
Our Invention relates to the better and more economical construction of
regenerative furnaces and hearths for the manufacture of steel or other metals or
minerals, whereby a more direct impingement of the hot gases upon the liquid
metal, a deflecting furnace roof independent of the ports, a convenient form of
cinder trap, an improved reversing valve, and a useful recess below the hearth are
obtained.
We so construct our furnace that the whole of the side flues for admission of
the currents of air and gas upon the surface of the molten metal are built upon the
main substructure of the furnace, and entirely independent of the deflecting furnace
roof.
The entering faces of the flue towards the furnace are made in a turned arch,
concave towards the hearth, and which may be made to overhang the hearth at a
considerable angle.
The arches are fixed securely in this overhanging position by strong wrought
iron stays or ties attached to the body of the furnace, so that when the deflecting
furnace roof is built in between the flue faces, the latter approach closely the sides
of the roof, but do not in any way rest upon it, nor are they dependent upon the
stability of the roof for support.
In case then of collapse of or wear the roof, which is of small dimensions, the
flue faces and flues remain entire and firm, and the furnace roof can be easily and
economically renewed. Owing to the overhang thus given to the furnace faces of
the gas and air flues, these latter can be conveniently and safely set out to a
considerable angle of impingement upon the surface of the metal bath, even to so
great an angle as 45° if desired.
We have also so improved the substructure of our furnace that we can bring the
regenerator directly under the escaping current of hot gases from the furnace
without weakening the arched substructure, instead of through ports formed
in the keying of the arches supporting a principal part of the furnace, as used
heretofore.
We also form convenient cinder traps in the floor of the gas exit flues close to
the furnace, so that the bottom of the pockets is on the working floor level, and the
cinder may be conveniently extracted at that level.
We construct our hearth so that it is supported on girders over an open area of
considerable depth in the substructure of the furnace, which communicates around
the sides of the furnace bridges with ventilation exits into the open air. This area
or recess underneath the hearth is thus exceedingly useful, both to keep the under
side of the hearth as cool as possible and to facilitate access for repairs.
We also apply an improved form of valve for reversing the action of the gases
through the regenerator. The valve may be of the ordinary D shape, travelling
over three ports, but instead of a sliding motion upon the port faces we move the
valve by a rocking lever from beneath, which thus lifts the valve slightly from one
seat and drops it rapidly upon the other. This motion is more easily effected than
a slide when the seats are gummy and sticky.
And in order that our Invention may be the better understood we now proceed
to describe the Drawings hereto annexed, reference being had to the figures and
letters marked thereon,
Figures I. and II. are sectional elevations of our furnace taken at right angles to

page_text: each other, and Figure III. is a sectional elevation through the reversing valves
showing an outside elevation of the furnace itself; like letters refer to similar parts
in each of the Figures.
The side flues A, A, for the admission of air and gas are built upon the main
substructure of the furnace B, and entirely independent of the deflecting roof C.
The entering faces of the flues A towards the furnace are made in the turned
arches D concave to the hearth E, which are made to overhang the hearth E to a
considerable degree so as to give an effective impingement of the gas and air upon
the bath of molten metal.
The arches D are secured in their overhanging position by strong wrought iron
stays F, which may be formed of angle iron, as shown, or in any other convenient
manner. These stays F are secured to cross pieces G, which are again fixed to the
main wrought iron supports H of the structure.
The deflecting roof C does not therefore rest in any way upon the side flues A
or their casing, nor are the latter dependent upon the stability of the roof C for
their support.
The angle or overhang so obtained for the entering flues and their faces is thus
much greater than could be safely given by any other form of construction.
K, K, are the regenerators so situated in the substructure that they are directly
under the current of hot gases escaping from the furnace through the flue L. The
flue L passes by the side of the main arch M, supporting the super-structure, and
thus without weakening the arcb, as is usually done, by forming ports in the keying
of the arch.
N is a cinder trap formed in each gas exit flue close to the furnace, and so con-
structed that the bottom of the pocket is on the level of the working floor O.
The cinder may be thus conveniently extracted through a man hole P at that level.
The hearth E is supported on girders Y (formed conveniently from old rails) over
an open area Q of considerable depth in the substructure of the furnace which
communicates round the sides of the furnace bridges with ventilation exits R into
the open air. This open area is thus both useful for effecting repairs and also to
keep the underside of the hearth cool.
S, S, in Figures II. and III., show sectional elevations at right angles to each other
of our improved reversing valve. They are conveniently made partly of cast and
partly of wrought iron, and are of the ordinary D shape, closed above and open
below, with planed under faces where they work on the three ports T. Each valve
is enclosed for protection in an external case V open at the top. This valve S is
moved from port to port so as to reverse the passage of the hot gases by a rocking
lever W with handle W₁. This rocking lever passes underneath the valve so as to
lift it slightly from its seating and drops it on the other seating when required.
This motion is more easily effected than a slide when the seats are gummy.
The special stayed arched port or flue faces as herein described may be applied
with slight alteration to any form of regenerative furnace at present in use, and
the staying may be used only over the arched face, and down the sides of the
furnace, where it may be built into the brick work at the bottom, in the case of
other iron staying not being used.
In the event of a movable hearth being used between the blast and regenerative
furnaces, so that the molten iron from the blast furnace can be run direct into the
hearth of the regenerative furnace, the before described system of furnace and the
construction of the ports therein are most favourable for the application of such a
hearth, and we reserve liberty to make such alterations as may be required in our
designs to effect this object.
And having now described and ascertained the nature and object of our
Invention and the manner in which it is to be performed, be it known that what
we consider novel and useful and desire to protect by our Letters Patent is,
1st. The construction in any regenerative furnace of an overhanging port and
flue face independent of the roof, and supported in position by iron stays,
substantially as described.

page_text: 2nd. In a regenerative furnace the construction of a cinder trap of which the
bottom is on a level with the working floor, substantially as described.
3rd. In a regenerative furnace an improved reversing valve lifting from seat to
seat instead of sliding thereon, substantially as described.
4th. In a regenerative furnace a ventilated recess below and around the hearth,
substantially as described.
In witness whereof, I, the said Allan Carswell Wylie, on behalf of myself and
the said Thomas Lockerbie, have hereunto set my hand and seal, this
Twenty first day of June, in the year of our Lord One thousand eight
hundred and eighty one.
In the presence of
S. P. WILDING,
23, Rood Lane,
London, E.C.,
Patent Agent.
ALLAN C. WYLIE. (L.S.)