IMPROVEMENTS IN CENTRAL DRAFT FLUES FOR FURNACES OR KILNS FOR THE CALCINING OF LIME, THE ROASTING OF ORES, AND THE BURNING OF CEMENT AND PLASTER, AND OTHER MATERIALS."
Year: 1877

page_text: LETTERS PATENT to Adrian John Verkouteren, of Amsterdam, in the Kingdom
of Holland, but at present of Gracechurch Street, in the City of London, in the
County of Middlesex, for the Invention of "IMPROVEMENTS IN CENTRAL DRAFT
FLUES FOR FURNACES OR KILNS FOR THE CALCINING OF LIME, THE ROASTING
OF ORES, AND THE BURNING OF CEMENT AND PLASTER, AND OTHER MATERIALS."
A communication from abroad by William Smith Sampson, of the City and
State of New York, United States of America.
Sealed the 20th July 1877, and dated the 22nd March 1877.
PROVISIONAL SPECIFICATION left by the said Adrian John Verkouteren
at the Office of the Commissioners of Patents on the 22nd March 1877.
ADRIAN JOHN VERKOUTEREN, of Amsterdam, in the Kingdom of Holland, but
at present of Gracechurch Street, in the City of London, in the County of Middle-
sex. "IMPROVEMENTS IN CENTRAL DRAFT FLUES FOR FURNACES OR KILNS FOR
THE CALCINING OF LIME, THE ROASTING OF ORES, AND THE BURNING OF CEMENT
AND PLASTER, AND OTHER MATERIALS." A communication from abroad by William
Smith Sampson, of the City and State of New York, in the United States of
America.
The object of this Invention is to provide a method of increasing and better con-
trolling the draft in furnaces or kilns which are designed for and used in the
calcining of lime, the roasting of ores, and the burning of cement and plaster, and
other materials. This is accomplished by drawing the flame and heat towards the
centre of the furnace or kiln, and through its contents, thereby insuring a more
regular and perfect combustion, giving a better control of fires, and increasing the
production of the furnace or kiln, and the means employed for producing these
results consist in the introduction into the furnace or kiln of a centrally suspended
draft flue, as herein-after described.
This draft flue varies in its dimensions, according to the depth and capacity of
the furnace into which it is to be inserted, and may be made of cast or wrought
metal, or other suitable materials. It is provided on its entire length with longi-

page_text: tudinal flanges, each projection in each section of the flue (if the latter is formed in
sections) forming one-half of each flange. These sections of which the flue may be
formed are held firmly together by means of bolts and nuts, the said flanges having
returning flanges at their outer edges, extending the entire length of the flue, for
the purpose of protecting the heads of the bolts from injury.
Through the walls of the flue in each section, between the longitudinal flanges,
are formed a series of openings or inlets, which openings are provided for the
purpose of permitting the free passage of the smoke and gases from the fires into
the flue, and thence to the open air through the flue and stack. These openings or
inlets are of any desired number, and are placed at such intervals in the length of
the flue as will cause a free draft towards them from the fires in the fire-chambers
at the base of the furnace or kiln.
The longitudinal flanges of the flue and their returning flanges also serve to form
chambers or spaces on the exterior surface of the flue, which spaces materially aid
the draft of the kiln. They also serve to protect the main body of the flue from
excessive friction caused by the rapid descent of the contents of the kiln following
the intervals of drawing.
Instead of forming the flue in sections it may be constructed of sheet iron,
properly riveted together, and provided with longitudinal strips of angle iron on the
outside at about equal distances apart, running its full length, to take the place of
the longitudinal projecting flanges, herein-before referred to.
The flue is made tapered from top to bottom, the base being the smallest in
diameter. This form of construction is very important and essential for the purpose
of protecting the flue from injury, and preventing it from being carried down with
the charge of material when it is following in a mass after each draw. By reason
of this tapering form of the flue the material composing the contents of the furnace
or kiln, in consequence of descending in vertical lines, falls away from the flue,
hence the flue remains steadily in position and undisturbed when the material again
settles down. The flue at its apex is provided with a projecting collar which rests
on supporting bars, which rest on the top of the furnace walls, the entire arrange-
ment being such that the flue is enabled to swing in its support to some extent, so
that in case the charge of material in the furnace or kiln presses against it more in
one direction than another it will be free to move and relieve itself from such
pressure without undue strain upon itself or upon its supports.
Any other suitable arrangement for supporting the flue may be employed, and
.may be varied to suit the requirements of cach particular case.
The stack or chimney may be of any ordinary construction, and of sheet metal,
of such length, shape, and diameter as cach case may demand, and is provided with
a damper of the ordinary form for the purpose of regulating the draft.
It will be understood that the application of this centrally suspended draft fluc
is to "perpetual furnaces and kilns" only, which furnaces or kilns are provided
with one or more fire-chambers in the walls of and near the base of such kilns, and
that this Invention is not intended for the so-called "set kilns," into which the
fuel and material are charged in alternate layers, or mixed. These kilns have no
fire-chambers, and the burned, roasted, or calcined material, refuse, and ashes are
usually drawn therefrom together.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Adrian John Verkouteren in the Great Seal Patent Office on the
20th September 1877.
ADRIAN JOHN VERKOUTEREN, of Amsterdam, in the Kingdom of Holland, but at 50
present of Gracechurch Street, in the City of London, in the County of Middlesex.
"IMPROVEMENTS IN CENTRAL DRAFT FLUES FOR FURNACES OR KILNS FOR THE

page_text: CALCINING OF LIME, THE ROASTING OF ORES, AND THE BURNING OF CEMENT
AND PLASTER, AND OTHER MATERIALS." A communication from abroad by William
Smith Sampson, of the City and State of New York, in the United States of
America.
The object of this Invention is to provide a method of increasing and better con-
trolling the draft in furnaces or kilns which are designed for and used in the
calcining of lime, the roasting of ores, and the burning of cement and plaster, and
other materials. This is accomplished by drawing the flame and heat towards the
centre of the furnace or kiln, and through its contents, thereby insuring a more
regular and perfect combustion, giving a better control over the fires, and increasing
the production of the furnace or kiln. The means employed for producing these
results consist in the introduction into the furnace or kiln of a centrally suspended
draught flue as herein-after described.
This draught flue varies in its dimensions, according to the depth and capacity of
the furnace into which it is to he inserted, and may be inade of cast or wrought
metal, or other suitable material or materials. The flue may be formed in sections,
and in that case is provided throughout its entire length with longitudinal flanges,
each of which projects in each section of the flue, forming one-half of each flange.
The sections of the flue (when the latter is so constructed) are held firmly together
by means of bolts and nuts; the said flanges have returning flanges at their outer
edges extending the entire length of the flue for the purpose of protecting the
heads of the bolts from injury.
Through the walls of the Hue in each section, between the longitudinal flanges,
arc formed a series of openings or inlets, which openings or inlets are provided for
the purpose of permitting the free passage of the smoke and gases from the fires
into the flue, and thence to the open air through the flue and stack; these openings
or inlets are of any desired number and shape, and are placed at such intervals in
the length of the flue as will cause a free draught towards them from the fires in the
fire-chambers at the base of the furnace or kiln.
The longitudinal flanges of the flue, together with the returning flanges, serve
also to form chambers or spaces on the exterior surface of the flue, which chambers
or spaces materially aid the draught of the kiln, and also serve to protect the main
body of the flue from any excessive friction which may be caused by the rapid
descent of the contents of the kiln following the intervals of drawing.
Instead of forming the flue in sections, as herein-before described, the same may
be also constructed of sheet iron, properly rivetted, welded, or fastened together, and
provided with longitudinal strips of angle iron on the outside, at about equal
distances apart, throughout its entire length, to take the place of the longitudinal
projecting flanges herein-before referred to.
The flue is tapered from top to bottom, the base being the smallest part thereof
in diameter. This form of construction is very important for the purpose of pro-
tecting the flue from injury and preventing it from being carried down with the
charge of material when the latter is following in a mass after each draw. By
means of this tapering form of the flue the material which is contained in the
furnace or kiln, in consequence of descending in vertical lines, falls away from the
flue, which remains steadily in position and undisturbed when the material again
settles down. The flue at its apex is provided with a projecting collar which rests
on supporting bars, and which bars rest on the top of the furnace walls, the entire
arrangement being such that the flue is enabled to swing in its supports to some
extent, so that in case the charge of material in the furnace or kiln presses against
it more in one direction than another, it will be free to move and relieve itself
from such pressure without undue strain upon itself or upon its supports.
Any other suitable arrangement for supporting the flue may be employed and
varied to suit the requirements of each particular case.
The stack or chimney may be of any ordinary construction, and of such material
or materials, length, shape, and diameter as each case may require, and should be

page_text: provided with a damper of the ordinary and well-known kind for the purpose of
regulating the draught.
I will now proceed to refer to the annexed Drawings from which the nature of
the said Invention will be more clearly understood.
Figure 1 is a sectional elevation of an ordinary furnace or kiln to which the
before-mentioned improved draught flue is applied; Figures 2 and 3 are respectively
enlarged sectional views of the draught flue taken on the line x, x, in Figure 1.
The same lotters of reference indicate similar parts in the several Figures.
Figure 1 shows the centrally suspended draught flue as applied to an ordinary lime
kiln or furnace, the base of which, at its centre, is raised for the purpose of chuting
or impelling the calcined materials towards the draw doors N, which are of the
ordinary construction; G is the wall of the kiln; R the fire-brick lining; and S, the
usual narrow dead air-space between the walls as a provision for their expansion;
O are the fire-chambers, and a the ash-pits, the same being respectively of the
ordinary construction. In Figure 1 A represents the centrally suspended draught flue,
and J the smoke stack or chimney, both being shown in their proper position in the
kiln, their lengths and diameters varying with the depth and capacity of the furnace
or kiln into which they are to be inserted. The draught flue may be (as hercin-before
mentioned) constructed of cast or wrought iron, or other suitable material or
materials, all in one piece, or in parts, bolted, rivetted, welded, or so fastened
together as may be requisite or desirable.
'
In the instance illustrated in the annexed Drawings the draught flue is constructed
in four sections (1, 2, 3, 4, as shewn in Figures 2 and 3) of cast or wrought metal,
which are provided throughout their entire length with the longitudinal flanges C
having returning flanges E at their outer edges. The said four sections which form
the complete flue are held together by bolts and nuts, the heads of which are pro-
tected from injury by the said returning flanges which purposely extend over the
entire length of the fluo as herein-before mentioned.
In the case of the flue not being made in sections, but all in one or more picces,
ribs, angle irons, or other suitable projections are cast or fastened on its outside at
proper distances apart for strengthening the said flue, and for other purposes herein-
after mentioned. Through the walls of the fluo in each section, between the flanges
C, are formed a series of openings or inlets F (as shewn in Figure 1) for the purposes
herein-before mentioned. The before-mentioned flanges, C and E, of the flue
serve to form also the chambers or spaces on the exterior surface of the flue, as
herein-before mentioned; I is a projecting collar at the apex of the flue, supported
on the bars H so as to allow the flue partially to swing. The smoke stack or
chimney is shewn at J, and the damper at R.
Having thus declared and ascertained the nature of the said Invention and in
what manner the same is to be performed, I declare in conclusion that what I
consider novel and original, and therefore claim as constituting the Invention
secured by the said in part recited Letters Patent are,―
First. The combination with a furnace or other suitable kiln arranged and
adapted for the calcining of lime, the roasting of ores, the burning of cement and
plaster, and other materials (the said furnace or kiln being provided with one or
inore fire-chambers and ash-pits in its circumference near to its base) of a centrally
suspended draught flue; made tapering from top to bottom, and by means of which the
heat, gases, and flame, are drawn from the fire-chambers through the charge of
stone, ore, or other inaterials, towards the centre of the furnace or kiln to such
fluc, escaping therefrom, substantially as and for the purposes hercin set forth.
Secondly. The employment of a draught flue to be suspended in a furnace or kiln,
arranged and adapted for the purposes aforesaid, the said draught flue being made
tapering from its apex to its base, and provided with longitudinal flanges or pro-
jections with or without returning flanges, the whole combined, arranged, and
operating substantially as and for the purposes herein set forth and described.
And, Thirdly. The smoke stack or chimney, provided with a damper in com-

page_text: bination with a draught flue, suspended in a furnace or kiln arranged and operating
substantially as and for the purposes herein set forth and described.
In witness whereof, I, the said Adrian John Verkouteren, have hereunto set
my hand and seal, this Seventeenth day of September, in the year of our
Lord One thousand eight hundred and seventy-seven.
A. J. VERKOUTEREN.
(L.S.)