IMPROVEMENTS IN FURNACES
Year: 1873

page_text: LETTERS PATENT to Andrew Howatson, of Cronberry, Auchinleck, in
the County of Ayr, N.B., and Octavius Williams, of Swansea, in
the County of Glamorgan, Civil Engineer, for the Invention of
T
"
PROVISIONAL SPECIFICATION left by the said Andrew Howatson and
Octavius Williams at the Office of the Commissioners of Patents,
with their Petition, on the 19th May 1873.
We, ANDREW HOWATSON, of Cronberry, Auchinleck, in the County
of Ayr, N.B., and OCTAVIUS WILLIAMS, of Swansea, in the County of
Glamorgan, Civil Engineer, do declare the nature of the said Invention
for "IMPROVEMENTS IN FURNACES," to be as follows :-
The improvements have reference to furnaces employed in the
conversion of crude malleable iron into finished plates, bars, rods, sheets,
and such like, and commonly known by the term hollow or brick fire,

page_text: and consist in so constructing and working the furnace that a great
economy may be effected both in time and fuel, by utilizing the other-
wise waste heat for heating the hot blast by using raw coal or coal
mixed with coke in lieu of coke only, by making three or more side
doors instead of two as before, by notching the sole plates of the side
doors to receive and suit the staff or rod of metal used, by placing
under the bed of the furnace coke or charcoal to retain heat.
The improvements may be performed by building a furnace of fire-
brick or other suitable material with a chimney stack, leaving under the
bed of the furnace and sometimes at the sides or top thereof a hollow
flue or flues for the admission and reception of air. Also taking up
the chimney stack hollow air flues, the feeding with raw coal may be
effected by means of a hopper or hoppers so that the coal comes on to
the top or surface of the fire.<<
The side doors and sole plates may be constructed of metal, but having
a convenient notch formed in the sole plate for the reception of the staff,
so that there may be little or no escape of heat when the staff is in
work; the bed of the furnace may be made sunk to receive a layer or
layers of coke or charcoal.
SPECIFICATION in pursuance of the conditions of the Letters Patent, 2
filed by the said Andrew Howatson and Octavius Williams in
the Great Seal Patent Office on the 19th November 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, ANDREW
HOWATSON, of Cronberry, Auchinleck, in the County of Ayr, N.B., and
OCTAVIUS WILLIAMS, of Swansea, in the County of Glamorgan, Civil 2
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of November, in the year
of our Lord One thousand eight hundred and seventy-three, in the thirty-
sixth year of Her reign, did for Herself, Her heirs and successors, give 3
and grant unto us, the said Andrew Howatson and Octavius Williams,
Her special licence, that we, the said Andrew Howatson and Octavius
Williams, our executors, administrators, and assigns, or such others as

page_text: we, the said Andrew Howatson and Octavius Williams, our 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
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
FURNACES," upon the condition (amongst others) that we, the said Andrew
Howatson and Octavius Williams, our executors or administrators, by an
instrument in writing under our, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said Inven-
tion, 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 we, the said Andrew Howatson and Octavius
Williams, do hereby declare the nature of our said Invention, and in
what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
_
The Invention has reference to certain improvements in that class of
furnace known as the "hollow" or "brick" fire employed for con-
verting crude malleable iron into metal suitable for finished plates,
bars, rods, sheets, or metallic articles of a similar nature. The objects this
Invention is designed to accomplish are economizing the consumption of
fuel, and saving time during the process.
The Invention may be thus described :-The furnace or hollow fire
is constructed of any convenient form, and may be composed of fire-
brick or other suitable material. The chimney stack of the furnace is
supplied internally with metallic pipes, tubes, or flues, which at a
certain altitude pass through the wall of the chimney so as to form
openings or entrances thereto from the outside for the admission of cold
air or blast. The air after passing through these pipes in the chimney,
during which it absorbs the waste heat from the furnace, is conveyed
by passages under and about the hollow furnace, during which its heat
becomes considerably intensified. In this state it is distributed through
thoroughfares into the fire, where it becomes the only medium for
supplying the furnace with hot blast or heated gases of combustion.
The chimney stack is provided with a damper that regulates the exit or
escape of the expended gases or products of combustion.

page_text: The thoroughfares or passages conveying the heated air to the furnace
from the heat absorbing pipes in the chimney are arranged and so con-
structed that they pass through the top sides or other portions of the
structure from which heat radiates, so that whilst the exterior of the
furnace is kept comparatively cool the blast is proportionately raised in
temperature. The fuel we prefer to use is coal, coke, or a mixture of
the two, or any combustible material which may prove a convenient or
economical substitute. This fuel is fed to the furnace by means of a
hopper or hoppers so placed that it will be received on to the top or
surface of the fire.
In the construction of the ordinary hollow fire in which the iron to
be heated is placed immediately over the fuel we make the cast-iron
bottom thereof double, having a space between, or with two plates per-
forated for the passage of the blast before reaching the fire. The fore
plates or supports for the iron operated upon which are situated below
the fire-doors are also formed hollow for the passage of the blast. The
structure or hollow furnace may also be provided with an intermediate
chamber supplied with fuel which is designed to counteract any oxi-
dizing tendency there might be in the gases passing from the generator
caused by inattention to the fire or from an excessive supply of air. In
order to prevent the escape of heat from the furnace at the point where
the "staff "of the operator is inserted the side doors and sole plates are
composed of metal, the sole plate being provided with a small notch or
hole for the reception of the staff. By this arrangement the escape of
heat through the "staff hole" is reduced to a minimum.
In order that the Invention may be better understood and explained
in detail we have hereunto annexed a Sheet of Drawings made on a scale
of about one half inch to the foot, similar letters of reference being
marked on corresponding parts on all the Figures.
DESCRIPTION OF DRAWINGS.
Fig. 1 represents in longitudinal vertical section that class of furnace
and chimney employed in the conversion of crude malleable iron into
iron of a superior sort and in which our improvements are shewn
applied.
Fig. 2 represents a modification of the hollow furnace shewn in Fig. 1
having applied thereto a generator of the same construction, and
Fig. 3 represents in plan a horizontal section of Fig. 1 taken through
the line x, xe

page_text: In these Figures a is the generator which may be either rectangular
or cylindrical in section and charged with any description of fuel capable
of producing sufficient heat. The capacity of this generator will depend
upon the number of furnaces to which it may be attached. It is
protected with iron plates in the ordinary manner and is provided with a
perforated fire-brick bottom a¹ or if desired iron fire-bars may be employed
arranged on the well-known step system; b is the body of the furnace,
its dimensions transversely being similar to that of an ordinary hollow
or brick fire. The furnace b is fitted with a series of doors on one or
both sides thereof (their position being shewn in dots on Figs. 1, 2, and
in the detached Fig. 4) which are opened when the furnace is being
charged or the iron removed. The bottom of the furnace b would in
commencing operations be first covered with clear coke or other fuel,
which would tend to equalize the heat on the charge of iron. c is the
ash pit provided with a door c¹ which must be made so as to fit well to
its seating. d is the chimney in which the blast heating pipes or flues
are fixed or as a modification of these pipes, flues may be made in the
brick work of the chimney; d' is a damper provided for regulating and
adjusting the escape of vapours or gases from the chimney and which
maintains by its adjustment a pressure in the body of the furnace when
in action slightly in excess to that of the atmosphere, and which pressure
is generally termed a "plenum"; e, e, are the metal pipes fixed in the
chimney which absorb the escaping or waste heat and transmit it to the
air or cold blast passing through the pipes to the furnace. The cold air
regulated by a valve or cock is first received into these pipes through the
external orifice e¹; f, f, are hoppers for charging the generator and
supplementary furnace with fuel; g is the furnace bottom which be
constructed as a passage or channel for conveying the hot blast from the
chimney pipes c to the furnace. If so employed it will be expedient
to use a layer of brickwork under the bottom side in order to prevent
the radiation of heat. The arrangement shewn in Fig. 2 dispenses with
this passage or channel, the hot air from the pipes e being delivered
into a chamber e underneath the furnace from whence it is delivered to
the generator. The arrangement of thoroughfares h, shewn in Fig. 1, for
passing the hot air to the generator and which may also be employed
with advantage in the arrangement shewn at Fig. 2 consists in passing
the hot blast from the channel g into the ash pit c under the fire-bars
through the medium of the pipe h; is a supplementary furnace or
receptacle for fuel, the object and employment of which is designed to
i
may

page_text: neutralize any free or unconsumed atmospheric air that may be passing
through the generator; k is a pipe provided with a valve or cock through
which heated air is allowed to pass into the hollow bridge the effect of
which would be to consume the vapour or gases produced in the generator.
This arrangement is equally applicable to the furnace Fig. 2. 1, 1, are
the cast-iron fore plates (which may be made hollow for heating the
blast) supporting the "staffs or handles of the iron blooms with which
the workman operates upon the iron; m, m, are recesses or holes through
which the "staffs" are inserted into the furnace. The recesses are made
with a view of checking as far as possible the escape of heat from
the furnace.
"
Having now described the nature of our said Invention, together with
the method of carrying the same into practical effect, we wish it to be
distinctly understood in conclusion that the object sought by this
Invention and which it is our desire to claim is,-
First. The novel employment and adaptation to hollow furnaces and
their chimneys of heat absorbing pipes and passages so arranged that cold.
blast entering the same will have transmitted to it heat radiating and
escaping from such furnace and which gives to such air a high
temperature, in which state it is fed as hot blast into the generator.
Secondly. The novel employment and use of a supplementary furnace
or a receptacle for fuel i, together with the general arrangement of parts
constituting the Invention to be used in the manner and for the purposes
as hercin-before substantially described, set forth, and fully illustrated in
the Drawings annexed.
In witness whereof, we, the said Andrew Howatson and Octavius
Williams have hereunto set our hands and seals, this Eighteenth
day of November, in the year of our Lord One thousand eight
hundred and seventy-three.
Witnesses,
HUB. MAJOR.
R. B. HowATSON.
ANDREW HOWATSON. (L.S.)
OCT. WILLIAMS.
(L.S.)