Improvements in Steam Doners.
Year: 1894

page_text: Date of Application, 21st Feb., 1894
Complete Specification Left, 20th Nov., 1894-Accepted, 26th Jan., 1895
Improvements in Steam Doners.
We, JAMES WEIR, GEORGE WEIR, and JOHN RITCHIE RICHMOND, all of
Holm Foundry, Cathcart, in the County of Renfrew, North Britain, Engineers,
do hereby declare the nature of this invention to be as follows, that is to say:
1
Our said invention has for its object to improve the construction of steam
boilers, and it comprises certain modes of arranging water tubes in combination
with other parts in a manner to secure efficient circulation of the water without
priming tendency.
In carrying out our invention according to one modification we construct a
central vertical shell of a convenient extent horizontally and surmounted by a
horizontal cylindrical shell or enlargement which serves mainly as steam space.
Water tubes are fixed in both sides of the central vertical shell and are of curved
forms, the lower ends of all of them being fixed below a certain level whilst the
upper ends of all of them are fixed above that level; so that steam entering
the central vertical shell from the upper end of any tube cannot interfere with
water entering the lower end of any other tube. The tubes are, on each side,
arranged in two or more stacks or sets, and the tubes of a lower set extend
outwards to a less distance than those of an upper set, the lower tubes crossing
up between the lower parts of the upper tubes and returning to the central
The tubes are, by
vertical shell below the upper parts of the upper tubes.
preference of graduated sizes, those which are situated so as from length or from
position as regards heat in a manner to have steam the more rapidly formed in
them being made the larger.
Furnaces are arranged at each side of the central vertical shell under the water
tubes; and the whole is enclosed in a casing which may consist mainly of iron
lined with firebrick. The several furnaces are made with ashpit doors or openings,
with the usual doors just above the level of the grate bars to be used for cleaning
purposes; whilst doors are provided at a higher level for stoking.
The central vertical shell is made with flat sides of sufficient strength and
connected with cross stays; and parts of the plates to which the stays are fixed
may be slightly dished or indented for the purpose of distributing the tension of
the stays over the plates. Inside of the central vertical shell deflecting plates may
be placed at the upper part facing and near the upper ends of the tubes for the
purpose of deflecting the streams of steam upwards and facilitating separation from
the water.
In a somewhat similar boiler made according to another modification the central
vertical shell is made with enlargements along its lower and upper parts, such
enlargements being preferably of curved forms. The tubes have their lower ends
fixed into the bottom enlargement and their upper ends into the upper enlarge-
ment; and the upper enlargement may either partly form the steam space or it
may communicate with a higher steam cylinder or vessel. The furnace grates are
placed within the tubes, above the lower outgoing parts of the tubes, and under
and within the upper returning parts of the tubes, there being spaces for ash pits
between the lower parts of the tubes and the grates and spaces for combustion
chambers above the grates. The lower parts of the tubes are covered by plates, or

page_text: the uppermost of those tubes are arranged close together; and the close arrange-
ment of the tubes is continued up round the grates to some distance above them, or
plates or firebrick partitions are applied to prevent the fire gases from entering
amongst the tubes excepting at their upper parts. The outer rows of the tubes are
encased or made close at all parts excepting under and near the bottom enlargement
of the central vertical shell, at which part a flue or pair of flues is formed leading
to an uptake or chimney. With this arrangement the fire gases enter amongst the
tubes at their upper parts and then proceed downwards along and amongst the
tubes to their lower ends. The currents of the fire gases are thus opposite to those
of the water and steam in the tubes, an arrangement conducive to a maximum
exchange of heat between the fire gases and the water. The central vertical shell
may be made parallel-sided or of widths increasing towards the top, and current-
dividing or circulating plates may be arranged inside of it so that steam formed in
contact with the shell may ascend without interfering with the descending water.
The modifications of boiler hereinbefore described may be made single instead of
double, that is with tubes and furnaces on one side only of what has been termed
the central vertical shell; and in such cases such shell which is for the descending
water may be inclined or curved; and in some cases the furnace doors may be
formed through it.
An important improvement applicable to the boilers hereinbefore described and
to other water-tube boilers, consists in contracting the tubes by ferrules or rings or
otherwise at the ends at which the water enters them. This improvement by the
contraction and by increasing the velocity of the water entering the tubes prevents
the circulation through the tubes from being checked and water being forced
backwards by the irregular and abrupt formation of steam in the tubes. When
using ferrules for the purpose described we prefer to have them projecting into the
shell and made with perforations or serrated edges.
בז-זבוב
TTTTATEN
EDMUND HUN
Applicants' Agent.
We, JAMES WEIR, GEORGE WEIR, and JOHN RITCHIE RICHMOND, all of
Holm Foundry, Cathcart, in the County of Renfrew, North Britain, Engineers,
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, that is to say :-
Our said invention has for its object to improve the construction of steam boilers,
and it comprises certain modes of arranging water tubes in combination with other
parts in a manner to secure efficient circulation of the water without priming
tendency.
Examples of water-tube boilers embodying our improvements are delineated
two accompanying sheets of explanatory drawings which are hereinafter
referred to.
on
Figures, 1, and, 2, on Sheet, 1, of the drawings are transverse vertical half
sections of two modifications of boiler; and Figure, 3, is a transverse vertical
section of a third modification. A fourth modification is shown in Figures, 4,
and, 5, which are sectional end and side elevations. Figures, 6, and, 7, on
Sheet, 2, are transverse vertical sections of fifth and sixth modifications; and
Figures, 8, to, 11, are enlarged views of details. In these drawings the same
reference letters and numerals are used to mark the same or like parts wherever
they are repeated.
In carrying out our invention according to modifications of which Figure, 1,

page_text: represents an example we construct a central vertical shell, A, of a convenient
extent horizontally (at right angles to the figure) and surmounted by a horizontal
cylindrical shell, A 1, cr as shown in Figure, 1, by an enlargement, A 1, which
serves mainly as steam space. Water tubes, B, are fixed in both sides of the
central vertical shell, A, A 1, and are of curved forms, the lower ends of all of them
being fixed below a certain level, whilst the upper ends of all of them are fixed
above that level; so that steam entering the central vertical shell, A, A 1, from
the upper end of any tube cannot interfere with water entering the lower end of
any other tube. The tubes, B, are on each side arranged in two or more stacks or
sets; and the tubes of a lower set, B 1, extend outwards to a less distance than
those of an upper set, B2, the lower tubes crossing up between the lower parts of
the upper tubes and returning to the central vertical shell or its upper enlarge-
ment, A 1, below the upper parts of the upper tubes. The tubes, B, may be of
graduated sizes, those which are situated so as from length, or from position as
regards heat, in a manner to have steam the more rapidly formed in them being
made the larger. Furnaces, C, are arranged at each side under the water
tubes, B; and the whole is enclosed in a casing, D, which may consist mainly of
iron lined with firebrick. The several furnaces, C, are made with ashpit doors or
openings, with the usual doors, C1, just above the level of the grate bars to be
used for cleaning purposes; whilst doors, C2, are provided at a higher level for
stoking.
The central vertical shell, A, may be made with flat sides of sufficient strength
and connected with cross stays (which however are not shown in Figure, 1) and
parts of the plates to which the stays are fixed may be slightly dished or indented
for the purpose of distributing the tension of the stays over the plates.
In a second modification of boiler, shown in Figure, 2, the central vertical
shell, A, is made with an upper enlargement, A 1; and it and the shell of the first
modification may be made with lower enlargements also. The tubes, B, have their
lower ends fixed in the lower part or lower enlargement of the central shell, A, their
upper ends being fixed in the upper enlargement, A 1; and the upper enlargement
may either partly form the steam space, or it may communicate with a higher
steam cylinder or vessel. The furnace grates, C, are placed within the tubes, B,
and under and within the upper returning parts of the tubes, there being
spaces, C3, for ashpits between the lower parts of the tubes and the grates, and
spaces for combustion chambers above the grates. The lower parts of the
tubes, B, are covered by plates, or the uppermost of those tubes are arranged close
together; and the close arrangement of the tubes is continued up round the grates
to some distance above them or plates or firebrick partitions are applied to prevent
the fire gases from entering amongst the tubes excepting at their upper parts.
The outer rows of the tubes, B, are encased or made close at all parts excepting
under and near their bottom ends below which part a flue, E, or pair of flues leads
to an uptake or chimney. With this arrangement the fire gases enter amongst the
tubes at their upper parts, and proceed downwards along and amongst the tubes to
their lower ends and the flue, E. The currents of the fire gases are thus opposite
to those of the water and steam in the tubes, an arrangement conducive to a
maximum exchange of heat between the fire gases and the water.
In the third and fourth modifications shown in Figures, 3, 4, and, 5, the parts
corresponding to what have herein before been referred to as upper and lower
enlargements are in the form of upper and lower cylindrical shells, A1, A2, and
are connected, not by a central vertical shell extending from end to end of the
boiler, but by comparatively narrow vertical shells or one or more large vertical
tubes, A, through which water in circulating descends from the upper cylinder, A 1,
to the lower one, A 2. In these examples a single large furnace, C, is arranged
within the tubes, B, on both sides. In the modification shown in Figure, 3, the
fire gases are by plates or close arrangement of portions of the tubes, made to pass
downwards amongst the tubes, B, on one side (the right-hand side in the figure)
and to return upwards on the other side to a chimney, F. In the modification

page_text: shown in Figures, 4, and, 5, 'the fire gases pass in two streams from the furnace, C,
at each end of the boiler, downwards amongst the tubes, B, to bottom flues, E,
leading to two chimneys, F.
The modifications of boilers herein before described may be made single, that is,
as shown in Figures, 6, and, 7. In the fifth modification, Figure, 6, the upper and
lower cylinders, A1, A2, are connected by a flat-sided shell, A, which has
openings made through it for a fire door and for the ash pit. In the sixth
modification Figure, 7, the upper and lower cylinders, A 1, A 2, are connected by
large tubes, A.
An important improvement applicable to the boilers herein before described and
to other water-tube boilers, consists in contracting the tubes, B, by terrules or
short tubes at the ends at which the water enters them. This improvement, by the
contraction and by increasing the velocity of the water entering the tubes prevents
the circulation through the tubes from being checked and water being forced
backwards by the irregular and abrupt formation of steam in the tubes. Figure, 8,
shows an inlet end of a water tube, B, with a ferrule or short tube, G, fixed in it;
and Figures, 9, and, 10, shown in each case a number of tubes, B, so contracted.
We prefer to have the ferrules or short tubes, G, projecting into the shell, A. 2, as
shown in Figures, 8, to 11, and they may be made with perforations as shown, the
plain ferrule is however quite efficient. When the tubes, B, are fixed in the
upper part of the shell, A 2, as shown in Figure, 9, the ferrules, G, may be all of
one length; but when fixed in the lower part of the shell, A2, as shown in
Figure, 10, we prefer the ferrules, G, to be of increasing lengths in order
downwards.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. The improved combination and arrangement of parts substantially constituting
the boiler herein before described as the first modification.
2. The improved combination and arrangement of parts substantially constituting
the boiler herein before described as the second modification.
3. The improved combination and arrangement of parts substantially constituting
the boiler herein before described as the third modification.
4. The improved combination and arrangement of parts substantially constituting
the boiler hereinbefore described as the fourth modification.
5. The improved combination and arrangement of parts substantially constituting
the boiler hereinbefore described as the fifth modification.
6. The improved combination and arrangement of parts substantially constituting
the boiler hereinbefore described as the sixth modification.
7. In a water tube boiler the arrangement of tubes curved away and upwards
from a lower cylinder or water shell and returning inwards at their upper parts
to an upper cylinder or equivalent, combined with the arrangement of one or
more furnaces in the space or spaces between the lower and upper parts of the
tubes substantially as hereinbefore described.
8. In a water-tube boiler contracting the inlet ends of the tubes by short tubes
or ferrules projecting into the water cylinder or shell substantially in the manner
and for the purposes hereinbefore described.
Dated this Nineteenth day of November 1894.
EDMUND HUNT,
Applicants' Agent.