An Improvement in Water-tube Boilers.
Year: 1889

page_text: Date of Application, 11th Nov., 1889
Complete Specification Left, 11th Aug., 1890-Accepted, 13th Sept., 1890
PROVISIONAL SPECIFICATION.
An Improvement in Water-tube Boilers.
I, ALFRED FERNANDEZ YARROW of Isle of Dogs Poplar in the County of
Middlesex Engineer, do hereby declare tho nature of this invention to be as
follows:-
My invention relates to a simple, strong and comparatively light construction of
water tube boiler. I provide two bottom water chambers at some distance apart with
the furnace and flame space between them; and, above these, provide an upper
chamber for water and steam situated at the apex of a triangle having the two lower
chambers at the extremities of its base. Each of the lower chambers is preferably
semicylindrical having a cover approximately flat flange jointed to it, this cover having
holes through it so as to constitute a tube plate and lying at an angle. I make the
upper chamber preferably cylindrical, in two halves, flange jointed together, and 1
bore in its lower side two sets of holes for tubes corresponding with those of the tube
plates below. Between the upper chamber and each of the lower chambers I fix a
number of straight or approximately straight tubes which lie at an angle, all those on
the one side parallel or nearly so to one another and all those on the other side parallel
or nearly so to one another. I secure the tubes in the usual way either by screwing
or by expanding their ends in the holes. By undoing the flanges and removing the
bottom parts of the lower chambers I get access to the lower ends of the tubes, and
by removing the upper half of the upper chamber, I get access to the upper ends of
the tubes. I enclose the boiler within a suitable casing containing the furnace in its
lower part and leading to a chimney above so that the flame and hot products of com-
bustion pass through the spaces between the tubes on each side on their way from the
fire to the chimney.
Instead of a single upper chamber receiving both sets of tubes, there may be two
chambers side by side, the one receiving the one set of tubes and the other receiving
the other set of tubes. When there are two upper chambers they may be placed
parallel to one another in such a position that the tubes which extend from the lower
chambers to the upper chambers, cross one another, the right hand upper chamber
receiving the tubes from the left hand lower chamber and conversely.
It is of advantage to introduce between rows of the tubes baffle plates so arranged
that the hot products of combustion, instead of passing directly through the intervals
between the tubes, have to take a zig zag course on their way to the chimney. Instead
of employing baffle plates for this purpose, or in addition to baffle plates, some of the
rows of the tubes may be arranged to cross one another so as locally to obstruct the
passages between them.
Dated this 11th day of November 1889.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improvement in Water-tube Boilers.
1, ALFRED FERNANDEZ YARROW of Isle of Dogs Poplar in the County of Middlesex,
Engineer, do hereby declare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and by the
following statement :
My invention relates to a simple, strong and comparatively light construction of
water tube boiler. I provide two bottom water chambers at some distance apart

page_text: with the furnace and flame space between them; and, above these I provide an
upper chamber for water and steam situated at the apex of a triangle having the two
lower chambers at the extremities of its base. Each of the lower chambers is prefer-
ably semi-cylindrical having a cover approximately flat flange jointed to it, this
cover having holes through it so as to constitute a tube plate and lying at an angle.
I make the upper chamber preferably cylindrical in two parts, flange jointed together
and I bore in its lower side two sets of holes for tubes corresponding with those of
the tube plates below. Between the upper chamber and each of the lower chambers
I fix a number of straight or approximately straight tubes which lie at an angle, all
those on the one sido parallel or nearly so to one another and all those on the other
side parallel or nearly so to one another. I secure the tubes in the usual way either
by screwing or by expanding their ends in the holes. By undoing the flanges and
removing the bottom parts of the lower chambers I get access to the lower ends of
the tubes, and by removing the upper part of the upper chamber, I get access to the
upper ends of the tubes. I enclose the boiler within a suitable casing containing the
furnace in its lower part and leading to a chimney above so that the flame and hot
products of combustion pass through the spaces between the tubes on each side on
their way from the fire to the chimney.
Instead of a single upper chamber receiving both sets of tubes, there may be two
chambers side by side, the one receiving the one set of tubes and the other receiving
the other set of tubes. When there are two upper chambers they may be placed
parallel to one another in such a position that the sets of tubes which extend from the
lower chambers to the upper chambers may or may not cross one another in the former
case the right hand upper chamber receiving the tubes from the left hand lower
chamber and conversely.
It is of advantage to introduce between rows of the tubes baffle plates so arranged
that the hot products of combustion, instead of passing directly through the intervals
between the tubes, have to take a zig zag course on their way to the chimney. Instead
of employing baffle plates for this purpose, or in addition to baffle plates, some of the
rows of the tubes may be arranged to cross one another so as locally to obstruct the
passages between them.
Figure 1 of the accompanying drawings shews a part end elevation and part
cross section of the first herein before described construction of my improved water
tube boilers.
Figure 2 shews a longitudinal section of the same. A is the upper cylindrical water
and steam chamber, formed in two halves secured together by flanges A', and B B
are the two bottom water chambers, connected to the chamber A by the water tubes C.
The lower chambers are constructed of a semi-cylindrical part B' closed by an
approximately flat cover B bolted to flanges on B1 and having holes into which aro
screwed or otherwise fixed the lower ends of the tubes C, the upper ends of which are
:screwed or otherwise fixed in holes formed in the chamber A. Dis the furnace situated
between the bottom chambers BB, the flames being made to pass transversely between
the water tubes on their way to the uptake E; F is the casing of the boiler.
In place of a single upper chamber A, there may be two such placed side by side.
Longitudinal baffle plates may be provided hetween the tubes C so as to cause the
flames and combustion gases to take a circuitous course, on their way to the chimney,
or in lieu hereof the modified arrangement shewn at Figure 3 may be adopted, in
which the tubes of the middle and outer rows are made to cross each other at the
middle, so as to obstruct the passage of the flames and gasos at that part, and thus
cause them to take the circuitous course indicated by the arrows, fire brick checks D¹
being provided at the sides of the furnace to obstruct the direct passage of the flames,
between the lower ends of the inner rows. Tubes G of larger diameter connect the
chambers A and B B at the end, outside the casing, for effecting the downward
.circulation of the water.
Fig. 4 shews a cross section and Figure 5 a side view of the herein before.
described modified construction wherein there are two upper steam and water
chambers A A, constructed similar in form to the lower ones B B to which they are

page_text: connected by the tubes CC in such a manner that the two sets of tubes cross each
other over the furnace as shewn so that as the part where the tubes cross each other
acts as a baffle, the flames and hot gases are made to effectually penetrate first between
the lower ends of the tubes and then between the upper ends on their way to the
uptake E.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. Constructing water tube boilers of an upper steam and water chamber A. or of
two such chambers formed in two parts bolted together and two bottom water
chambers B B of semi-cylindrical or equivalent form closed by a cover of an
approximately flat shape to which are connected the lower ends of the water tubes CC
that establish the communication between the upper and lower chambers, substantially
as herein described with reference to Figs. 1, 2 and 3 of the drawings.
2. In water tube boilers such as are referred to in the first claim, arranging the
water tubes of some of the rows to cross each other, so as, in obstructing the passage
of the flames and gases at the point of crossing, to cause them to take a circuitous-
route between the tubes substantially as described.
3. Constructing water tube boilers of two upper steam and water chambers A A
of semi-circular or equivalent form closed by an approximately flat cover, and two
lower water chambers B B, connected to the upper chambers by water tubes CC so
arranged that the two sets of tubes cross cach other over the furnace, substantially as
described with reference to Figures 4 and 5 of the drawings.
Dated this 11th day of August 1890.
ABEL & IMRAY,
Agents for the Applicant.