Improvements in the Construction of Steam Boilers Applicable for the Heating and Evaporating of Fluids.
Year: 1887

page_text: Date of Application, 19th Jan.; 1887
Complete Left, 17th Oct., 1887
Complete Accepted, 29th Nov., 1887
Improvements in the Construction of Steam Boilers Applicable for
the Heating and Evaporating of Fluids.
I WILLIAM WALLER of Hasland near Chesterfield in the County of Derby
Engineer do hereby declare the nature of this invention to be as follows :-
The objects of this Invention are, to secure the free expansion of the several
portions of the fabric of the boiler without unduly adding to the strain upon
another portion or portions of the same; the regular circulation of the fluid within
the boiler, and the deposit of the grosser particles carried with the fluid in the coolest
position or place in the boiler in order to avoid as much as possible the formation of
scale; and further to economise the heat given off from the burning fuel by checking
its too rapid passage to the outlet, and by presenting to the action of the heat or
heated gases a greater contact surface, thus promoting and effecting economy of fuel
with greater evaporating power without adding materially to the cost size or weight
of the boiler.
My improvements consist,-
1. In substituting, for the solid or hollow screwed stays used in firebox or water
space boilers, a cup or conical or hollow vessel which is screwed into the inner wall
of the firebox, or is otherwise attached to it and passing into the water space it is
secured to the outer wall by a screw formed either on the stay or passing through it
and the plate of the outer wall, thus giving greater support to the plates and adding
to the heating surface; or the position of this vessel can be reversed and screwed
into or otherwise attached to the inner wall of the firebox or furnace, or into or to
the combustion chamber or uptake and it projects into the flame or heated gases
having the end beyond the screwed part regulated in size and strength of metal to
the width of the water space, so that the base is pressed against the outer wall,
provision being made for the free ingress and egress of water to the heated end
through which a screwed stay or bolt passes to the outside of the firebox where it is
secured forming a firm stay and a valuable aid to rapid steam raising.
A modification of this part of my invention consists in the substitution of a tube
for the bolt or stay in order to allow fuel in a dust or fluid form being introduced by

page_text: a steam and air jet or either of them into the middle of the furnace or combustion
chamber.
2. Another part of my improvements consists, in the application and use in the
construction of boilers of plates which have been treated by pressing blocking or
working by any known method so as to add to their strength or power of
resistance, such as,-buckled plates, or plates worked rivetted or marked on one
or both sides with round square hexagon octagon or other suitable figures, which when
stayed to the outside wall plate will prove in the whole a strong and effective firebox
plate; alternate cup or conical faced continuous curves or lines can be formed so
that one side shall press against the outer wall plate while the other receives the stay
bolt.
3. Another part of my improvements relates to the tubes which lead the products
of combustion from the firebox or furnace or from the uptake through the fluid to
the smoke box or funnel.-It is well known that there is great waste of fuel by the
gases passing through these tubes without having given off their heat; longer and
smaller tubes have been substituted with the view of remedying this defect, as well
as other plans and expedients but with only partial success. Now I propose to
introduce into some or all of these flue tubes internal tubes containing water, these
internal tubes being preferably placed in connection with the lower part of the
chimney or smoke box end of the boiler to receive their supply, they then pass
along the flue tubes concentrically with them, or nearly so, into the firebox; they are
attached to some part of the firebox above their then level to discharge the steam
formed in them into the water and steam space of the boiler. Not only does this
give a great increase of heating surface but the gases cannot pass along the annular
space so provided, without parting with the greater portion of their heat by the
contact thus secured.
Or the water can be passed and repassed along these internal tubes if found
desirable, or some of these internal tubes can be used for heating the feed water, or
for superheating the steam.
4. Another and further part of my improvements consists in forming a sediment
chamber under the boiler shell, by preference at the end furthest from the fire, into
which chamber the scum is led (by an internal plate fitted within the shell) in a
fluid state and from which it may be blown off at intervals.-The feed water can be
delivered into this sediment chamber from which one or more pipes lead to the
lower part of the firebox water space and the regular circulation of the water is
ensured.
Dated this 17th day of January 1887.
BRISTOW HUNT,
Agent for the Applicant.

page_text: Improvements in the Construction of Steam Boilers Applicable for
the Heating and Evaporating of Fluids.
I WILLIAM WALLER of Hasland near Chesterfield in the County of Derby
Mechanical 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 said invention consists Firstly in substituting for the solid screwed stays used
in firebox or water space boilers shewn on Drawings (Sheet No. 1 and Figures 1
and 2) or for the hollow tube stay (Fig. 3) screwed and passing through the outer
plate a, the water space i, and the firebox plate 6, securing them in position.
A cup or conical or hollow vessel or tube which is to be screwed into the wall plate
of the firebox b, or otherwise attached to it, and passing into the waterspace i, be
secured to the outer plate a by being screwed into it (as Figs. 4. 5) by a screw
forming part of the stay, or (as Fig. 6) by a screw bolt passing through the end of
such cup or vessel and the outer plate a thus giving greater support to the plates and
adding to the heating surface of the firebox, furnace, combustion chamber, or
uptake.
I do not claim that the application of a cup or conical or hollow vessel or tube to the
sides of a firebox, or furnace, or combustion chamber, or uptake, is new, or even the
placing such vessel upon the crown of a firebox, or furnace, whether projecting into
the water, or into the flame and heated gasses; but that such application as a stay, or
forming a portion of a stay, whether in one piece or of several constituting a good
and sufficient stay for the wall plates of the outer and inner sides against the pressure
between them, and providing the means of carrying heat into the water, or water into
the heated gasses without there being a clear passage through such stay, unless by its
being connected with another similar stay, is new, and will prove a valuable addition
to the steam generating power of a boiler at the hottest and most favourable position,
I have good reason for believing.
In giving some sketches shewing the various ways in which, among others, this
improvement may be applied, whereby the end sought for may be attained, I do not
confine myself to any size or shape, as there may arise cases in which special and
complex arrangements are required. The simplest form of applying this improvement is
by screwing a cap on the outer end of the hollow tube stay shewn in Fig. 3 and pre-
venting the admission of air, while the heat from the inside will have free access to
the tube to give off its effect to the water surrounding it.
Or the position of this vessel may be reversed and screwed into or otherwise
attached to the inner wall of the firebox, or combustion chamber, or uptake and
project into the flame or heated gasses, the interior of the cup or conical or hollow
vessel or tube being filled with water from the water-space, provision being made
for the free ingress and egress of water. In this reversed position also the scrow for

page_text: attaching the vessel to the outer plate a may be part of the vessel, or may be a screwed
bolt passing through the vessel and the outer plate.
Sheet 2-Fig. 7-shews a cup for use with the present stays, to be screwed into
the firebox plate in the space between the four stays and having a sleeve or tube
passing through the water-space i and pressing against the outer plate a. Fig. 8
shows the cup without the tube or sleeve in the water-space i, but with the screwed
attachment to a forming a portion of it.
Fig. 9 shews a similar stay with both sleeve and stay bolt in one.
Fig. 10 is a similar stay but with the stay bolt f passing through the vessel h, the
firebox plate b, the water space i, and the outer plato a, not being in one piece.
Fig. Il shews an enlarged chamber h without the sleeve and with separate screw
bolt for staying the outer plate.
Shoet 3. Fig. 12 is a simple application of a piece of wrought iron pipe screwed
from the firebox against the outer plate, secured with a locknut and having a coupling
and plug at the firebox end with provision for the screw bolt to brace all together to
the outer plate.
Fig. 13 differs from Fig. 12 in having a "Tee" or X piece instead of a coupling
and plug at the inner end for the purpose of connecting two or more of these vessels,
by pipes or tubes in the flame or heated gasses.
Figs. 14. 15. are two modifications of the stay with detached bolt.
Fig. 16 is another design for the vessel in one piece to receive the ends of two
or more of the water tubes referred to in a later part of this Specification, the sockets
for which may be placed at any required angle.
A modification of this part of my invention consists of the substitution of a tube for
the screw bolt fin connection with the vessel & in order to allow fuel in a dust or fluid
form being introduced by a steam and air jet or either of them into the middle of
the furnace, or combustion chamber, forming water breasts or tuyeres to protect the
plates as shewn in Sheet 4 Figs. 17. 18.
Secondly Another part of my improvements consists in the application and use in
the construction of boilers, of plates which have been treated by pressing, blocking,
or working by any known method so as to add to their strength or power of resistance,
Plates worked revetted or marked on one or both sides with round, square,
hexagon, octagon, or other suitable figures, which when stayed to the outside plates
will prove strong and efficient firebox, or furnace plates, having alternate cup or
conical faced continuous curves or lines.
Sheet 5 Fig. 19 shews a section of the alternate cups and continuous curved
lines of a plate blocked to form the wall plate of a firebox, combustion chamber,
or uptake of a boiler, wherein each figure or indent supports and is supported
by those adjoining it and thus a strong plate with increased surface is obtained.
Fig. 20 shews a similar section with cones either square, hexagonal, or octagonal,
with continuous lines. The dotted projections are meant to shew studs or revets
which may be inserted it desired to give points of contact between these plates
and the outer plates, as named in my Provisional Specification.
Figs. 21. 22. are different sections with pointed tops to the figures.
Sheet 6. Figs. 23. 24. 25. are a faint attempt to shew the plan of the plates
when blocked but they would be unintelligible without the dotted sectional lines.
I wish it to be understood that Corrugated plates are not referred to in this
Specification, though the desired form sought to be obtained might be fairly
described as "corrugated lengthways and crosswise without destroying the original
figures."
Sheet No. 7 is meant to illustrate the blocking or buckling of the firebox plates
for a portable agricultural or locomotive boiler-thus Figs. 26. 27. are two examples
of the ordinary plan of buckling a plate suitable for the crown and side plates,

page_text: as described and shewn in the Specifications of Robert Mallet for other purposes
such as for flooring, bridges, and the perinanent way of railways (1865 No. 164) where
each plate is treated separately and worked into the required form within a stronger
margin, which forms a base on which it rests, and a support for the hollow
worked portion of the plate. But I prefer to have several square or diamond
shaped indents formed on the one side of the plate only for the crown plate,
such indents being placed with the apex towards the pressure to be borne, and
divided by narrow channels, running diagonally, to carry off and prevent the
deposit of dirt upon the plate. For the side plates I prefer those made with the
impressed cups or cones previously described.
Fig. 28 is the plate in which the firehole is, and is shown blocked to strengthen
the
plate where stays cannot be conveniently inserted.
Fig. 29 is another plan for strengthening the tube plate at the portion where the
barrel of the boiler comes in the way of the stays and prevents them being put in,
thus leaving a space of the tube plate without adequate support.
In using the terms Buckled and Worked as having distinct meanings I wish to
convey the reference to the plan introduced by Robert Mallet under the title adopted
by him, as indicating the shape given by pressure, a figuro projecting beyond the
plate on one side only, while by Working or Blocking 1 mean such shapes and figures
on both sides as are shown on Sheet 5. I am also aware that a system of blocking
by hydraulic pressure for flanging and dishing boiler plates is in use, but I have no
thought of including such in my description though the plates shown in Figs. 28. 29
are both flanged in addition to being worked as described. The intention is to
form in and upon the plates themselves certain cups cones and faces alternately
projecting into the flame and heated gasses, and into the water spaces, similar to
what have been described before in connection with tho stays in the first part of this
Specification.
Thirdly Another part of my improvement relates to the tubes which lead the pro-
ducts of combustion from the firebox or furnace or from the uptake through the fluid
to the smokebox or funnel. It is well known that there is great waste of fuel by the
gasses passing through these tubes without having given off their heat; longer and
smaller tubes have been substituted with the view of remedying this defect, as well
as other plans and expedients, but with only partial success.
The evil seems to suggest itself due in more or less degree to the absence of due
proportion between the areas of the firegrate space, the sectional area of the tubes,
and that of the funnel; the tube area being in excess of the latter. I
propose to
introduce into all or some of these flue tubes u (Sheets 89 Figs. 34. 35. 36) internal
tubes containing water, these internal tubes 1 (Sheets and Figs. as above) being pre-
ferably placed in connection with the lower part of the boiler at the smokebox or
chimney end to receive their supply (Sheet 9 Figs. 35 36) then passing along the
flue tubes u concentrically with them or nearly so, into the firebox (Sheet 8 Fig. 34)
they are connected to it at some part above their then level to discharge the steam
forined in them into the water and steam space of the boiler; or they may some or
all of them be connected to the stay chamber (Sheet 3. Fig. 16) to discharge the
heated contents into the water space e i. Not only does the introduction of these
internal tubes give a great increase of heating surface by their presence, but
the heated gasses cannot pass along the annular spaces (Sheet 8. Figs. 30. 32) so
formed without parting with the greater portion of their heat by the contact thus
secured.
Or the water may be passed and repassed along these internal tubes if found
desirable, as arrangement shewn (Sheet 8. Fig. 31), or from one flue tube to another
preferably directly above it.
Or some of these internal tubes may be used for heating the feed water, or for
superheating the steam.
The arrangement (Sheet 8. Fig. 33) has been designed for use as a retort in some
of the fluo tubes u of marine boilers for the volatilization of carbon oils for use in
the furnace, either all the internal tubes being so employed, or some for superheating

page_text: the steam for their combustion when the steam and oil gas are discharged thence in
intimate mixture at an intense heat.
Fourthly Another and further part of my improvements consists in forming in,
upon, or under, the boiler, preferably under it, a Sediment chamber, at or near the
end furthest from the furnace, into which chamber s, the scum formed on the top of
the water, and becoming denser than the water, may settle and be led by p and q, or
suitable pipes for the purpose (Sheet 9. Figs. 35. 36.) in a fluid state, and thence be
blown off from vat intervals. The feed water may also be delivered into this
chamber s at w. w. and thus the injury caused to the tubes by the impact of cold water
upon them be avoided.
From this chamber one or more pipes will be led to the lower part of the firebox
or furnace end of the boiler into the water space in order to ensure the regular
circulation of the water.
It is not claimed that the addition of a sediment chamber is new, or that a scum
collector and blow off pipe do not date back to an early time in the history of steam;
but the adaptation of the Sediment chamber to admit of the circulation of water freed
from deposit, and the return pipes a placed outside the boiler and away from the
influence of heat, are quite novel.

page_text: Or a similar fitting provided with foot or sleeve to press against the outer plate,
when projecting 'into the furnace, whether in connection with stays as now used,
or with a stay forming part of such fitting, or separately applied, substantially as
described.
Or, a similar fitting but larger with the stay formed of a tube instead of a stay bolt
for the admission of fuel in a dust or fluid form being introduced thereby into the
middle of the furnace or combustion chamber.
2. The application of Buckled plates for the fireboxes or furnaces of boilers with
modifications of the same for adding strength and efficiency to the same substantially
as described, and with or without stays and bolts.
Or the application and use of plates pressed, blocked, or worked, so as to present
alternately projections and recesses running from one to the other by continuous
curves or lines forming figures either round, square, diamond shaped, hexagon, octagon,
or other suitable shape, as described herein, for giving additional strength to the
plates, and increasing the superficial area to be presented to the flame, and to the
fluid.
3. The introduction into the fire or fluc tubes leading the flame and gasses from
the firebox, furnace, or combustion chamber, through the fluid, of internal tubes
which may be utilized as circulating tubes or for heating purposes, forming a con-
siderable addition to the heating surface of the boiler and tending to economise the
fuel by the compulsory contact of the heated gasses with both sides of the annular
space so formed.
4. The regulated circulation of the water for the generation of steam or evapo-
ration, by conducting it, in pipes externally to the boiler, from the part of the boiler
where the sediment has been deposited, to the furnace end of the boiler at a low
lovel.
D J 1 1
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