IMPROVEMENTS IN STEAM BOILERS
Year: 1877

page_text: LETTERS PATENT to James McKenzie, of Glasgow, in the County of Lanark;
North Britain, General Superintendent of the British India Steam Navigation
Company, for the Invention of "IMPROVEMENTS IN STEAM BOILERS."
ealed the 22nd January 1878, and dated the 31st July 1877.
PROVISIONAL SPECIFICATION left by the said James McKenzie at the
Office of the Commissioners of Patents on the 31st July 1877.
JAMES MCKENZIE, of Glasgow, in the County of Lanark, North Britain,
General Superintendent of the British India Steam Navigation Company. "IM-
PROVEMENTS IN STEAM BOILERS."
This Invention has for its object the constructing of steam boilers in an improved
and simple manner, and so as to be efficient and durable.
The improved boilers are of the vertical cylindrical class, with an internal
cylindrical space at the lower part, communicating with a central uptake which is
extended up through the top of the boiler. The internal cylindrical space is divided
diametrically by a water space extending from the bottom of the boiler up to near
the bottom of the central uptake. The diametrical water space divides the. interior
into two semi-cylindrical chambers, which form separate furnace spaces, uniting at
their upper parts. The fire-bars are arranged at the bottoms of the semi-cylindrical
chambers, and a separate fire-door is provided for each chamber.
Each semi-cylindrical chamber is in one modification crossed by a narrow
transverse vertical water space, the bottom of which is at a little distance above
the fire-bars, and which forms a communication between the diametrical water space
and the outer annular water space of the boiler.
The described construction provides a large and very effective heating surface in
a simple manner, and without parts that are liable to get out of order. Doors
provided in the outer shell of the boiler will give easy access for cleaning out the
diametrical and transverse water spaces.
In a second modification two transverse water spaces are fitted across each semi-
cylindrical chamber, and in large boilers there may be more than two transverse
water spaces in each chamber.

page_text: In a third modification the two semi-cylindrical chambers are traversed by
vertical water spaces placed parallel to the diametrical water space, instead of at
right angles to it.
In all the modifications the described construction is such as to cause a vigorous
and thorough circulation of the water, which is a feature of considerable practical
importance.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said James McKenzie in the Great Seal Patent Office on the 30th
January 1878.
IM-
JAMES MCKENZIE, of Glasgow, in the County of Lanark, North Britain,
General Superintendent of the British India Steam Navigation Company.
PROVEMENTS IN STEAM BOILERS."
My said Invention has for its object the constructing of steam boilers in an
improved and simple manner, and so as to be efficient and durable.
My improved boilers are of the vertical cylindrical class, with an internal
cylindrical or nearly cylindrical space at the lower part, communicating with a
central uptake, which is extended up through the top of the boiler. The internal
cylindrical space is divided diametrically by a vertical water space, and the semi-
cylindrical space on each side are divided each by one or two vertical water spaces
at right angles to the diametrical water space, or by a vertical water space parallel
to the diametrical one.
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 three modifications of my improved
boilers. In these Drawings the same reference numerals are used to mark the same
or like parts wherever they are repeated.
Figures 1 and 2, on Sheet 1 of the accompanying Drawings, are vertical and
horizontal sections of a modification of my improved boilers, which is suitable for
comparatively small sizes. The boiler is externally of a common form, having a
cylindrical shell 1 and a convex top 2, whilst there is within the lower part of it a
nearly cylindrical shell 3, the upper and smaller end of which has rivetted or welded
to it a flanged annular crown plate 4, from the centre of which an uptake 5 extends
up to and through the top 2, the usual chimney or funnel being attached above,
although not shown in the Drawing. A vertical water space 6 is fixed diametrically
across the space inside the inner shell 3, and, extending from near the bottom of the
boiler up to within a short distance of the bottom of the central uptake 5, divides
the internal space into two semi-cylindrical spaces communicating with each other
and with the uptake 5 at their upper ends. The semi-cylindrical spaces form two
furnace spaces, and the fire-bars 7 are placed at the bottoms of these spaces, whilst
each is provided with a firing door 8, so that the advantages of alternate firing may
be availed of.
Each semi-cylindrical furnace space is crossed by a narrow transverse vertical
water space 9, the bottom of which is at a little distance above the fire-bars 7, and
which forms a communication between the middle of the diametrical water space 6

page_text: and the outer annular water space 10 of the boiler, in addition to the communications
which that annular water space 10 has with the ends of the diametrical water
space 6.
The described construction provides a large and very effective heating surface in
a simple manner, and without parts that are liable to get out of order. Doors 11,
provided in the outer shell 1 of the boiler, will give easy access for cleaning out the
diametrical and transverse water spaces 6, 9. The diametrical water space 6 is by
preference made slightly narrower towards its bottom in order to facilitate the
introduction of the other water spaces 9 into their places.
A second modification, and one which I prefer for boilers of moderate size is shown
on Sheet 2 of the accompanying Drawings, Figures 3 and 4 being horizontal and
vertical sections, and Figures 5 and 6 a plan and an elevation.
In the arrangement of the parts this modification differs from the first in having
each semi-cylindrical furnace space divided by two transverse vertical water
spaces 9.
A third modification is shown in vertical and horizontal section in Figures 7 and 8,
on Sheet 1 of the accompanying Drawings, and in it each of the semi-cylindrical
water spaces is divided by a vertical water space 12, which is parallel to the
diametrical water space 6.
Instead of there being three parallel water spaces 12, 6, 12, across the interior of
the inner shell 3, as in the third modification, there may be two such parallel water
spaces placed so as to divide the entire space conveniently.
In all the modifications the tops of the water spaces 6, 9, 12, are at a little
distance below the crown plate 4, so that the several spaces above the fire-bars unite
at the top, where the several portions of the fire gases mix, and thence proceed
together up the uptake 5.
The described construction in all the modifications is such as to cause a vigorous
and thorough circulation of the water, which is a feature of considerable practical
importance.
Having thus particularly described my said Invention and the manner of
performing the same, I have to state that I do not restrict myself to the precise
details herein described or delineated, but that what I believe to be novel and
original, and claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,-
1. The dividing of the internal furnace space of a vertical steam boiler by a
vertical diametrical water space (6), and transverse vertical water spaces (9), the
parts being arranged or combined together in the inanner herein-before described.
2. The dividing of the internal furnace space of a vertical steam boiler by two or
three parallel vertical water spaces (6, 12,) the parts being arranged or combined
together in the manner herein-before described.
In witness whereof, I, the said James McKenzie, have hereunto set my hand
and seal, this Twenty-ninth day of January, in the year of our Lord One
thousand eight hundred and seventy-eight.
5 Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
J. MºKENZIE. (L.S.)