IMPROVEMENTS IN STEAM GENERATORS
Year: 1880

page_text: LETTERS PATENT to John Clayton Mewburn, of 169, Fleet Street, in the City
of London, Patent Agent and Consulting Engineer, for an Invention of
"IMPROVEMENTS IN STEAM GENERATORS." A communication from abroad by
Louis Dulac, of Lille, France.
PROVISIONAL SPECIFICATION left by the said John Clayton Mewburn
at the Office of the Commissioners of Patents on the 10th June 1880.
JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer. "IMPROVEMENTS IN STEAM GENERATORS."
[A communication from abroad by Louis Dulac, of Lille, France.]
The improved generator is composed of a series of water tubes, and of a cylindrical
barrel forming a steam reservoir, all being supported at their ends by brick walls.
The tubes and the reservoir can be placed longitudinally as usual or transversely.
The tubes are placed at an inclination, and are superposed quincuncially, so that
the flame passing between two tubes comes against the middle of the tube above,
and so on up to the reservoir. The smoke and gases are carried off by a flue which
may be horizontal or vertical, and in which a feed water heater may be fitted. The
circulation of the water is ensured by the inclination of the tubes, and by external
communications with the reservoir. The ends of the tubes are closed by cast iron
caps rivetted thereto, and each cap has at its upper and lower parts tubular necks
with flanged or other joints to allow of their being connected to corresponding
necks on the caps above and below, the necks on the uppermost tubes communicating
with the reservoir. At the upper end of the water tubes the necks are formed
internally to facilitate the rise of the water and steam; the necks at the lower end
are made so as to compel the water to enter the tube at the bottom; with this
object, a partition extends over nearly the whole section of the tube, only leaving
an opening at the lower part to allow the water to enter. The particles of steam
formed in the tubes necessarily rise towards the highest part and produce a very
active circulation. All the tubes thus connected together conduct the water to the
cylindrical reservoir on the ascending side, while on the descending side the water
flows from the reservoir and becomes divided among the tubes. On the descending
side a collecting pipe is fitted in which the sediment collects, and which can be
emptied by opening a cock. The feed water after having passed through the heater
mixes with the water descending from the cylindrical reservoir, a pipe being fitted
to communicate between the heater and one of the descending pipes. A steam
dome is fitted above the cylindrical reservoir. Each of the water tubes is provided
with a man hole and cover at the upper end, to enable the tube to be cleaned.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Clayton Mewburn, in the Great Seal Patent Office on the 6th
December 1880.
JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer. "IMPROVEMENTS IN STEAM GENERATORS."
(A communication from abroad by Louis Dulac, of Lille, France.)
The improved generator which forms the subject of this Invention is represented
in the annexed Drawings, and is composed of a series of water tubes B, B, and of a
cylindrical barrel C forming a steam reservoir, all being supported at their ends by
brick walls. The tubes B, B, and the reservoir C can be placed longitudinally as
usual or transversely as seen in the Drawings. The tubes are set at an inclination,
and are superposed quincuncially, so that the flame passing between two tubes
comes against the middle of the tube above, and so on up to the reservoir C. The
smoke and gases are carried off by a suitable flue, such as represented at E, which
may be horizontal or vertical, and in which a feed water heater R may be fitted
as shewn. The circulation of the water is ensured by the inclination of the
tubes B, B, and by external communications with the reservoir C. The ends of
the tubes are closed by cast iron caps u, u¹, rivetted thereto, and each cap has at
its upper and lower parts tubular necks with flanged or other joints, to allow of
their being connected to corresponding necks on the caps above and below, the
necks on the uppermost tubes communicating with the reservoir.
At the upper
end of the water tubes the necks u are formed internally to facilitate the rise of the
water and steam (see Figure 3); the necks u¹ at the lower end are made so as to
compel the water to enter the tube at the bottom; with this object, a partition (see
Figure 4) extends over nearly the whole section of the tube, only leaving an opening
at the lower part to allow the water to enter. The particles of steau formed in
the tubes necessarily rise toward the highest part, and produce a very active
circulation. All the tubes thus connected together conduct the water to the
cylindrical reservoir C on the ascending side u, while on the descending side u¹
the water flows from the reservoir and becomes divided among the tubes. On the
descending side a collecting pipe P is fitted in which the sediment collects, and
which can be emptied by opening the cock pl. The feed water after having passed
through the heater R mixes with the water descending from the cylindrical reservoir,
a pipe t being fitted to communicate between the heater and one of the descending
pipes u¹.
A steam dome D is fitted above the cylindrical reservoir C. Each of the
water tubes is provided with a manhole and cover at the upper end u, to enable
the tube to be cleaned.
By the improved construction of generator above described, the following
advantages are obtained-All the heating surface being over the flame, and at
only a short distance from the fire bars, that is to say, so as to be licked by the
flame, the maximum production of steam per unit of surface is ensured; the
circulation of water obtained by the inclination and external communication of the
tubes increases the power of production and keeps the tubes always clean inside;
each tube is free, and can readily be removed and replaced if required; the generator
can even work with one or more tubes temporarily removed; the examination and
repair are easy; all the joints are outside the brickwork, and therefore readily
attended to; there are no communications, joints, or supports in the flame, the
tubes being supported externally; the tubes being short, the expansion is
insignificant; each generator costs much less, occupies much less space, and requires
much less brick work than ordinary water tube generators of equal power; the
sediment can be removed while the generator is at work.
The number of tubes B and steam reservoirs C can be varied as desired, and so
can the means of external communication between the tubes and the reservoir.

page_text: And having now described the nature of the said Invention and in what
manner the same is to be performed, I declare that I claim,—
Constructing steam generators entirely of tubes and steam reservoirs with
inclinations and external communications, substantially as hereinbefore described
and represented in the annexed. Drawings.
In witness whereof, I, the said John Clayton Mewburn, have hereunto set
my hand and seal, this Second day of December, One thousand eight
hundred and eighty.
J. C. MEWBURN. (L.S.)