IMPROVEMENTS IN THE CONSTRUC- TION OR FORMATION OF METAL PLATES FOR INTERNAL FLUES AND FIRE- BOXES OF STEAM BOILERS
Year: 1877

page_text: LETTERS PATENT to Samson Fox, of the Leeds Forge, Leods, in the County of
York, Engineer, for the Invention of IMPROVEMENTS IN THE CONSTRUC-
TION OR FORMATION OF METAL PLATES FOR INTERNAL FLUES AND FIRE-
BOXES OF STEAM BOILERS."
Sealed the 1st September 1877, and dated the 19th March 1877.
PROVISIONAL SPECIFICATION left by the said Samson Fox at the Office
of the Commissioners of Patents on the 19th March 1877.
SAMSON Fox, of the Leeds Forge, Leeds, in the County of York, Engineer.
"IMPROVEMENTS IN THE CONSTRUCTION OR FORMATION OF METAL PLATES FOR
INTERNAL FLUES AND FIRE-BOXES OF STEAM BOILERS."
This Invention has for its object to impart increased strength and enlarged
heating surface to internal flues and fire-boxes of steam boilers by means of improve-
ments in the construction or formation of the metal plates with which those parts
are made.
Internal flues and fire-boxes of steam boilers are subjected to compressive strains,
which with the ordinary plates employed in their construction can be provided for
only with considerable difficulty and expense, whilst the provision made very often
proves ineffective. This Invention consists in imparting the necessary strength to
resist compression by constructing the flues and fire-boxes with metal plates having
a peculiar corrugated or undulated form, which at the same time presents an
enlarged heating surface. In the case of internal flues of horizontal cylindrical
boilers, the bottom plates of the flues may be plain plate, but the plates forming
the tops and sides of the flues are formed with corrugations running round or at
right angles to the axis of the fluc; and these corrugations whilst imparting the
desired increased strength to the plates present a series of transverse ridges to the
current of flames or fire-gases. The flues may in some cases be formed entirely with
corrugated plates, that is, with the bottoms corrugated as well as the top and sides.
The plates forming the top and sides of the steam boiler fire-box are also by this
Invention formed with corrugated plates.

page_text: The plates which may be of malleable iron or steel, or copper, or other suitable
metal, have the desired corrugated form given to them by suitably shaped rollers, or
by embossing or swaging them by means of a steam hammer or hydraulic press.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Samson Fox in the Great Seal Patent Office on the 19th
September 1877.
SAMSON Fox, of the Leeds Forge, 'Leeds, in the County of York, Engineer.
"IMPROVEMENTS IN THE CONSTRUCTION OR FORMATION OF METAL PLATES FOR
INTERNAL FLUES AND FIRE-BOXES OF STEAM BOILERS."
My said Invention has for its object to impart increased strength and enlarged
heating surface to internal flues and fire-boxes of steam boilers by means of improve-
ments in the construction or forination of the metal plates with which those parts
are made
Internal flues and fire-boxes of steam boilers are subjected to compressive strains,
which with the ordinary plates employed in their construction can be provided for
only with considerable difficulty and expence, whilst the provision made very often
proves ineffective. My Invention consists in imparting the necessary strength. to
resist compression by constructing the flues and fire-boxes in an improved and
peculiar inanner so as to have a corrugated or undulated form, which at the same
time presents an enlarged heating surface.
The plates, which may be of malleable iron, or steel, or copper, or other suitable
metal, have the desired corrugated form given to them by suitably shaped rollers, or
by embossing or swaging them by means of a steam hammer or hydraulic press, the
corrugations being imparted to the metal after it has been brought to the general
form of a flue or of a fire-box side.
And in order that my said Invention and the manner of performing the same
may be, properly understood I hereunto append two Sheets of explanatory
Drawings, to be herein-after referred to, and representing modifications of iny
improved boiler flues and fire-boxes, and apparatus to be used in making the same.
In these Drawings the same reference numerals are used to mark the same or like
parts wherever they are repeated.
Figure 1, on Sheet 1 of the accompanying Drawings, is a longitudinal vertical
section of one modification of my improved boiler flues, and Figure 2 is a corre-
sponding transverse vertical section. In this modification the bottom plate 1 of
the flue is a plain plate, but the plate 2 forming the top and sides is formed with
corrugations running round or at right angles to the axis of the flue, which cor-
rugations whilst imparting the desired increased strength to the flue present a
series of transverse ridges to the current of flames or fire gases passing through the
flue.
Figures 3 and 4 are longitudinal and transverse vertical sections of a boiler fitted
with a second modification of my improved corrugated flues. In this modification
the corrugations are formed completely round the flue. In making this flue, plain
sheet metal is first bended into a cylindrical form, and the joint is welded, after
which the cylinder or tube is brought to a red heat, and the corrugations are
formed in the metal either by rolling or by embossing or by swaging them. When
forming the corrugations by rolling the cylinder or tube I prefer to employ im-
proved machinery of the kind described in the Provisional Specification relative to
an application for Letters Patent made by me on 30 June 1877 (No. 2530).
Apparatus for forming the corrugations by embossing or swaging is herein-after
described.
Figures 5 and 6 are longitudinal and transverse vertical sections of a third modi-
fication of my improved corrugated flues. The corrugations are in this case carried
completely round the flue but in a helical (or spiral) direction instead of being
exactly at right angles to the axis of the flue.

page_text: Figures 7 and 8 are side and front elevations of the embossing or swaging
apparatus. To the vertically moving rod or bar 3 of a steam hammer there is keyed
instead of the ordinary block or head, a block 4, having corrugations formed on its
under side or face, whilst counterpart corrugations are formed on the upper surface
of a swago block 5 which is keyed to the anvil 6. This anvil 6 is made with a
recess or indent 7 to allow of the flue tube or cylinder being put with its upper
part resting on the swage block 5, and this block and the hammer block arc
made respectively with convex and concave forms to suit the round forms of the
flue, besides having the corrugations as heroin-before described.
An entire flue may be made up of lengths rivetted or welded together, and each
consisting of one or more plates welded into a cylindrical or tubular shape, and
having the corrugations formed on it when in that shape. The welded joints may
be longitudinal and transverse or inclined.
Figures 9 and 10, on Sheet 2 of the accompanying Drawings, are horizontal and
vertical sections showing the manner of carrying out the part of my Invention
relating to boiler fire-boxes, such as those of locomotives. I make the top plate 8,
the front plate 9, and the side plates 10, 11, of the fire-box with corrugations which
do not extend completely across each plate, but which leave uncorrugated borders
for the convenient attachment of the plates to each other by rivetting or welding;
and in addition to the corrugations I form the said plates 8, 9, 10, 11, each with a
general curvature which is convex towards the steam pressure, such general con-
vexity increasing the strength imparted by the corrugations. In the case of fire-
boxes the plates are welded or rivetted together after they have been corrugated
and otherwise curved. I also make that part of the outer shell of the boiler which
encloses the fire-box with corrugated plates, each having in addition a general
curvature which is convex towards the steam pressure acting between the inside of
the shell and the outside of the fire-box plates 8, 9, 10, 11.
Figures 11, 12, 13, 14, 15 represent sections of the proportions and forms of cor-
rugation which I consider to be the best adapted for general boiler construction. I
do not however limit myself to these forms. In the Drawings accompanying this
Specification Figures 11 to 15 are drawn two-thirds of the actual sizes.
Having thus particularly described my said Invention and the manner of per-
forming the same, I have to state that I do not restrict myself to the precise details
herein described or delineated, and that I am aware that corrugated formus have
been given to metal plates or sheets for various purposes, and do not therefore claim
such forms in themselves or generally; but that what I believe to bo novel and
original, and claim as secured to me by the herein-before in part recited Letters
Patent is,―
1. The constructing of flues of steam boilers, substantially in the manner herein-
before described with reference to Figures 1 and 2 of the accompanying Drawings.
2. The constructing of flues of steam boilers with corrugations extending round
them, and formed after the metal of the flue has been brought to the cylindrical
shape, substantially in the manner herein-before described with reference to
Figures 2 to 8 of the accompanying Drawings.
3. The constructing of steam boiler fire-boxes, substantially in the manner
herein-before described with reference to Figures 9 and 10 of the accompanying
Drawings.
In witness whereof, I, the said Samson Fox, 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