Improvements in or relating to Furnaces.
Year: 1897

page_text: Date of Application, 18th Nov., 1897
TIT
Arst Oant
4000
Arcentrd
10th Nov 1000
Date of Application, 18th Nov., 1897
4000
Complete Specification Lett, 17th Sept., 1808 Accepted, 19th Nov., 1808
PROVISIONAL SPECIFICATION.
Improvements in or relating to Furnaces.
I, WILLIAM GRIMSHAW STONES, of 183, Preston New Road, Blackburn,
in the County of Lancaster, Civil Engineer, do hereby declare the nature of my
said invention to be as follows:-
My invention relates to means for admitting air, steam or gaseous matter into
steam boiler and other furnaces, for consuming smoke or economising fuel, and
consists essentially of a metal pipe or tube, divided into two longitudinal passages,
flow and return, by a longitudinal mid-feather, with openings in the outer
wall of the return passage,-in combination with a covering or sleeve of fire-
brick, fire-proof or refractory material, in a continuous, or segmental form, with
means for renewal of said covering, allowing of the expansion or contraction of
the parts, and for keeping the tube and its covering in their proper positions
relatively to each other, and to the furnace.
Said metal or like tube (of which there are one, two or more for each furnace,
and which, by preference, extend from boiler front to fire-bridge, and in any
suitable relation to the grate and each other) is formed as aforesaid, with a mid-
feather, which divides it into two passages, and into one of which the air, steam
or other gaseous matter to be led into the furnace enters, and after passing along
said passage to the end. of the pipe, flows back along the other passage towards the
front of the furnace, and by means of lateral openings in the outer wall of said
passage, escapes into the furnace, and if impelled by force is projected on to the
burning fuel for supporting combustion.
The fire-brick or like covering aforesaid is, by preference, in tubular form, and
in or about twelve-inch sections with spigot and socket or like ends for joining
up to each other, and each section formed with openings corresponding to those
in the tube. In order to bring such openings opposite each other I provide the
tube with one or more ridges or projections, and the surrounding sleeve with one
or more recesses (or vice-versa), which when engaging with each other ensure of
the openings being in exact "register."
By so covering the tube I protect it from the action of the fire, and prevent
its burning out, and by making the covering in sections I permit of any part
being readily renewed. By forming the metal tube with the double passage I prevent
cold air being delivered direct into the furnace, since in having first to traverse
the length of the tube, such air is highly heated before escaping through the
openings. On the other hand, the introduction of cold air tends to keep the tube
cool, and the nett result is a very efficient appliance.
To support the tube, and to prevent its twisting, or altering the position of the
openings in relation to the fire, and for the purpose of facilitating renewal and
fixing, and allowing of expansion and contraction, I mount one end of the tube
in a cavity in the fire-bridge or other support, and provide it (the tube) with a
projecting tongue taking into a slot or recess of like shape, and I mount the other
end of said tube on a stud or pin taking into the mouth of the return passage of

page_text: the tube, and supported by a bracket on or about the boiler front. This stud is a
sliding fit, and whilst serving to support the tube, and close the end of the return
passage, allows of contraction or expansion.
'
To further improve the appliance I make the fire-brick covering of a size which
will leave a small air space betweeir it and the tube, and by means of the rib or
ribs and recess or recesses aforesaid hold the two concentric. I may also provide
the inlet end with means for connection to an air supply or blast pipe or to a
steam nozzle. A modification of my double (flow and return) pipe would be a
Ushaped tube with fire-proof covering arranged to suit.
Whilst chiefly intended for Lancashire boilers, I may adapt my invention for
water-tube, marine and other boilers, and I may vary the construction to suit
the exigencies of the case.
Dotod this 17th day of N 190~
WILLIAM GRIMSHAW STONES,
By John G. Wilson & Co.,
Agents.
COMPLETE SPECIFICATION.
Improvements in or relating to Furnaces.
+
M
(1 p
I, WILLIAM GRIMSHAW STONES, of 183, Preston New Road, Blackburn,
Civil 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 means for admitting air, steam or gaseous matter into
steam boiler and other furnaces, for consuming smoke or economising fuel, and
consists essentially of a metal pipe or tube, divided into two longitudinal
passages, flow-and-return,-by a longitudinal mid-feather (or equivalent means),
with openings in the outer wall of the return passage, in combination with a
covering or sleeve of fire-brick, fire-proof or refractory material in a continuous,
or segmental form, with means for renewal of said covering; allowing of the
expansion or contraction of the parts; and for keeping the tube and its covering
in their proper positions relatively to each other, and to the furnace.
Said metal or like tube (of which there are one, two or more for each furnace,
and which, by preference, extends from boiler or furnace front to fire-bridge, and
in any suitable relation to the grate) is formed as aforesaid with a mid-feather
which divides it into two passages, and into one of which the air, steam or other
gascous matter to be led into the furnace enters, and after passing along said
passage to the end of the pipe, flows back along the other passage towards the
front of the furnace, and by means of lateral openings in the outer wall of said
passage, escapes into the furnace, and if impelled by force is projected on to the
burning fuel for supporting combustion.
The fire-brick or like covering aforesaid is, by preference, in tubular form, and
in, or about, twelve-inch sections with "spigot-and-socket" or like ends for joining
up to each other, and each section is formed with openings corresponding to those
in the tube. In order to bring such openings opposite each other I provide the tube
with one or more ridges or projections and the surrounding sleeve with one or more
recesses (or vice-versa), which, when engaging with each other, ensure of the openings
being in exact register."
"
:
By so covering the tube I protect it from the action of the fire, and pre-
vent its burning out, and by making the covering in sections I permit of any part
being readily renewed: By forming the metal tube with the double passage I

page_text: prevent cold air being delivered into the furnace, since in having first to traverse
the length of the tube, such air is highly heated before escaping through the open-
ings. On the other hand, the introduction of comparatively cold air tends to keep
the tube cool, and the nett result is a very efficient appliance.
To support the tube, and to prevent its twisting, or altering the position of the
openings in relation to the fire, and for the purpose of facilitating renewal and
fixing, and allowing of expansion and contraction, I provide the tube with a pro-
jecting tongue taking into a slot or recess of like shape in the fire-bridge or other
support and I mount the other end of said tube on a stud or pin taking into the
mouth of the return passage of the tube, and supported by a bracket on or about,
the boiler or furnace front. This stud is a sliding fit, and whilst serving to sup-
port the tube, and close the end of, the return passage, allows of contraction or
expansion.
To further improve the appliance I make the fire-brick covering of a size which
will leave a small air space between it and the tube, and by means of the rib (or
ribs) and recess (or recesses) aforesaid hold the two concentric. I may also pro-
vide the inlet end with means for connection to an air supply or blast pipe, or to
a steam nozzle. A modification of my double (flow-and-return) pipe would be a
U shaped tube with fire-proof covering to suit.
Whilst chiefly intended for Lancashire boilers, I may adapt my invention to
water-tube, marine and other boilers, and I may vary the construction to suit the
exigencies of the case.
And in order that my said invention may be more readily understood and carried
into practical effect I have hereunto annexed three sheets of drawings and will
now proceed to describe the same with the assistance of the various figures and
reference numerals marked thereon. Like numerals denote like parts.
On Sheet One,
Fig. 1 illustrates a front exterior view, and
Fig. 2 a broken longitudinal section of one of the furnaces of a
similar boiler, with my invention applied thereto.
Lancashire" or
Fig. 3 illustrates a longitudinal section by a horizontal plane (about half actual
size and partly broken away) of one form of the "flow-and-return" tube, its fire-
proof covering and part of the furnace bridge.
Fig. 4 illustrates a transverse section of the tube and covering on line a—b
(see Fig. 3) looking towards the fire-bridge.
Figs. 5 and 6 illustrate certain details at the front end of the "flow-and-return "
tube.
On Sheet Two,
Figs. 7 to 13 illustrate further details, and modifications thereof, at the front
end of the "flow-and-return" tube.
Figs. 14 and 15 illustrate a modified form of the details at the rear end of the
"flow-and-return" tube.
Figs. 16 and 17 illustrate other forms of the "flow-and-return" tube adapted
to be supported at both ends.
Figs. 18 and 19 illustrate another form of the "flow-and-return
tube adapted
to be supported at the front end, and with a inodified form of fire-proof covering.
Fig. 20 illustrates a half cross section of Fig. 18.
" flow-and-
Figs. 21, 22 and 23 illustrate certain details shewn in Figs. 18 and 19.
Fig. 24 illustrates the application of the same construction of
return to the furnace of a water-tube boiler.
Figs. 25 and 26 illustrate the form of bearer used for supporting the rear end
of the tube in a water-tube or like boiler when it is desired to support the rear
end of the tube as well as the front end.
On Sheet Three
Figs. 27 and 28 are similar views to Figs. 1 and 2 (Sheet 1) and illustrate the
application of the details shewn in Figs. 11, 12 and 13 (see Sheet 2), and

page_text: Figs. 29, 30, 31, 32 and 33, which latter illustrate a further modification of the
tube, and further modifications of the details at the rear end of the tube.
Fig. 34 illustrates a cross-section of Fig. 29, and
Fig. 35 is a similar cross-section shewing another way in which the tube may
be encased and illustrating the manner of its radial adjustment in relation to the
furnace grate.
Referring to Sheet One, I arrange within the furnace (1) and in any suitable
position, but (by preference) at the side and near the crown of the furnace, and
extending from furnace front (3) to the fire-bridge (4),—a pipe or tube (2).—Such
tube is what may for convenience of description, be described as of a
flow-and-
return "
type, ie, embodying, or containing a passage, or passages which serve
to convey air, gaseous or other like matter to the rear, or fire-bridge end of the
tube, and return it towards the furnace front end of the tube, and
may therefore partake of various forms, for example, a tube with closed
end (5), and longitudinal division (5), producing flow cavity (6) and return
cavity (7), as shewn in Figs. 2, 3 and 4 (Sheet 1), a tube bent in the form of
the letter U, as shewn in Fig. 16 (Sheet 2), or a tube with one end closed, and a
smaller tube (or hollow division) (5*) within it, as shewn in Fig. 17 (Sheet 2).-
Such flow-and-return tubes when applied to Lancashire" or like boiler fur-
naces, and supported at both ends may be formed or provided with a projecting
tongue (8) adapted to take into a cavity of like shape and proportions in a
block (9) built into, or forming part of the fire-bridge, and thus be supported, as
well as caused to occupy a set position relatively to the furnace. There may be
two, or more cavities in the block to allow of variations.
"
The front, or opposite end of the "flow-and-return" tube when the tube is
supported at both ends, is supported by bracket (10) (see Figs. 5 and 6) fixed upon
the front of the furnace and formed or provided with pin or stud (11) adapted to
take into, and fit the return cavity (7) of tube (2), and thereby support the tube,
as well as close the end of the return cavity, as shewn by dotted lines in Figs. 6
and 8. In practice I form the stud upon a base (11) adapted to fit the
bracket (10) and be held therein by set screws (13) (see Figs. 7 and 8). The
flow cavity (6) comes opposite an opening (12), and thus provides a clear inlet to
the tube.
Into the opening (12) of bracket (10) I fit the bell-mouth (14), the narrower
end of which is of the cross-section shewn in Fig. 9, and which, when in position
may be secured by set-screw (15).
In the outer wall of return cavity (7) of said tube, I provide a series of holes (16)
of equal, or varying size, and in parallel, radial or other setting in relation to the
tube, or furnace.
Air, gaseous or other like matter intended to promote combustion of fuel, or
prevention of smoke, being supplied to tube (2) through bell-mouth (14), under
influence of fan, injector or natural draught, passes along cavity (6) until it
reaches the far, or closed end of tube (2), where it is directed into the cavity (7)
and flowing back along such return cavity towards the furnace front (as shewn
by the arrows) finds its way out through the holes (16) which being set at an
appropriate angle, or position, in relation to the furnace grate (as aforesaid)
direct the said matter on to the burning fuel, and thus supply additional oxygen
to the inflammable gases or promote combustion. This effects the desired economy
of fuel and prevention of smoke, or an increased duty than otherwise obtainable
from a given quantity of fuel.
It will be observed that apart from the supply of air, gaseous or other like
matter, such matter is projected on to the burning fuel in the best condition
possible for accomplishing the desired end, i.e., in a highly heated state, due to
the said matter being first caused to proceed to the far end of the furnace. In
addition to such advantage the heating of the air materially diminishes the wear
and tear of the furnace, in that it is not exposed to frequent expansion and con-
traction. On the other hand it will also be seen that the constant flow of com-

page_text: paratively cool air into the pipe, and such air being impelled to the rear end of
tube tends to prevent the tube burning away.
To further provide against the tube burning away I fit a covering of fire-proof
or refractory material, made up in segments (17) slipped on to the tube and pro-
vided with "spigot-and-socket" or overlapping ends, as shewn in Fig. 3. The
interior diameter of each segment is, by preference, larger than the external
diameter of the tube (2), hence an air space (2) is produced between tube and
covering, which further helps to prevent the tube burning away. Such space
may be filled with asbestos, or other non-conductor and (or) fire-proof material.
In each of such segments and corresponding in spacing to holes (16) in tube (2),
are holes (18). To retain each segment (17) and its holes (18) in proper relation
with those in tube (2) I form the tube with the ridge (19) (or recess) and each
segment (17) with a recess (20) (or ridge), and with the ridge and recess engaging
with each other, as shewn in Fig. 4, thereby locate the same. To keep the tube
and its covering concentric I may provide two (or more) ridges and recesses, as
shewn in Fig. 35, where two are shewn.
In lieu of forming the supporting bracket (10) with opening (12) and projec-
tion (11) (or base 11*) I may form it as a collar (21) (see Figs. 11, 12, 13), and
allow the end of tube (2) to fit therein as shewn in Fig. 28. In such modification
the cavity (7) is closed by block (7*).
The said collar is removably mounted in bracket (22) by means of T extension,
and T groove, or the like (see Figs. 11 and 27) and provided with set screw (23).
The bell-mouth (14) at its narrower end is, in this case, of circular section.
Also in lieu of moving projection (8) into different recesses of fire-clay block (9)
I may provide a circular block (24) fitting in block (25) and formed with holes (26)
through any opposite pair of which and a hole in the block (25) (see Fig. 15), a
pin or cottar (27) may pass and serve to locate the tube at different angles. Or,
I may provide the end of the tube (2) with one or more ridges (28) (see Figs. 29
and 30) adapted to engage with any one or more of a series of grooves (29*) in
metal block (30) built into fire-bridge, or other support, and thereby hold the
tube and its distributing holes (16) in any desired position relatively to the
furnace grate. In all the foregoing methods of mounting the ends of tube (2)
the tube is free to expand or contract without altering its effectual support. In-
stead of being formed on the tube end the ridge (28) may be in the block (30)
and the grooves (29) in the tube end.
The block (30) is provided with cavity (31) and holes (32) through which latter
a bolt may be passed for securing the block to a surrounding fire-clay covering
to the fire-bridge, or to both covering and fire-bridge.
"
In Fig. 24 I shew the application of my invention to a "water-tube" boiler, in
which the tube is supported from the front end only, and in Figs. 18 to 23 I shew
the details of one of such applications, the type of flow-and-return tube in
this case being, by preference, that with the mid-feather, or inner-and-outer
tubes. The front end (see Figs. 18 and 24) is supported by long sleeve (33) with
flanged extremity (see Fig. 21) fitted to the furnace front or like support, and the
inner sides of said sleeve provided with grooves (34) to allow of ridges (19) on
tube (2) to pass through. The end of the tube may be covered by a refractory
block (17) formed with sunk boss (17) adapted to enter cavity (35) on end of
tube (2), and engage with flanges (36) when given a slight turn, but such cap
may be formed as part of one of the segments (17***) and be held on by other
means.
When it is desired to support the tube at its rear end, say from the brick wall
or lining of the furnace I provide the block shewn in Figs. 25 and 26 the part (38)
of which fits in the said wall or lining, and the part (39) engages with the end
of the tube in like manner to block (17). To prevent segments (17***) of the
covering coming off I provide a ring or flange (2) (see Figs. 18 and 22).
In Figs. 3, 4, 14, 16, 17, 29 and 34 I shew the refractory material as directly

page_text: applied to the tube, but for the better mounting or fixing of the covering (which
is best in small pieces) I may provide a metal sleeve (37) (see Figs. 18, 20 and 35)
having a set of dovetail shaped ribs (or grooves) and on the fire-proof segments
provide dovetail grooves (or ribs), designed to enable the fire-proof segments to
be fixed at any time, whether before or after the tube (2) is placed in position
and thus permit of repair. without removing the tube in case of breakage. The
said dovetailed fire-proof segments may be applied to the tube (2) direct if desired.
The form of covering shewn in Figs. 2, 3, 4, 14, 16, 17, 29 and 34 also allows
of its renewal without removing the tube (2) from its position in the furnace,
by removing the front end support and threading the covering on through the
opening in the furnace front sustained for the time being by a bar or rod pro-
jecting into the passage (6).
In the modification shewn in Figs. 18, 20 and 35 the sleeve (37) is formed with
the ribs (37) and recesses (37) to receive the fire-proof segment (17***) (see
Figs. 20 and 35). The said tube is also formed with holes in correspondence with
holes (16), and (18). The steam jet or injector may be fixed in any suitable
manner, either as shewn in Fig. 28 at the entrance of bell mouth (14), or may
be taken into cavity (6), and for the still better introduction of air or gaseous
matter, and for more effectively impelling the air through holes (16) I may cause
the jet to extend to the rear end of cavity (6), and for impelling the air into the bell
mouth (14) provide a separate jet at the entrance to said bell mouth.
Although only one tube is shewn in Figs. 1 and 27 and such tube shewn sup-
ported by fixtures on the furnace front it will be understood that two or more
may be applied to each furnace and that they may be supported from the furnace
crown, or from or by other parts.
Having thus particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I wish it to be understood
that I do not confine myself to the precise details, relative proportions or dimen-
sions of the several parts herein described as the same may be varied to meet the
exigencies of each application without departing from my invention, and what
I claim is:-
:-
*
"
1: Supplying air, steam or gaseous matter to furnaces by means of a tube, or
tubes having "How-and-return
passages and lateral openings in the return
passage, and substantially as, and for the purposes, set forth."
2: A tube, or tubes with flow-and-return " passages and openings in the
return passage, in combination with a fire-proof or refractory covering, in one
or more parts, and formed with openings in correspondence with the said open-
ings in the tube, with means for locating it, or them, upon the tube, and producing
(by preference) an air space between, substantially as and for the purposes set forth.
3: A tube, or tubes with "flow-and-return
passages and holes in the return
passage, in combination with means for effecting the support and radial adjust-
ment of the said tube, and allowing of expansion and contraction thereof, sub-
stantially as, and for the purposes, herein described and illustrated on the
accompanying drawings.
4: A flow-and-return tube with mid-feather (5), ridge or ridges (19) (or
grooves), projection (8) or (28) and holes (16), as set forth and illustrated in
Figs. 3, 4 and 27 of the accompanying drawing.
5: Fireproof segments (17) or the like, with one or more grooves (or
ridges) (20), and holes (18), as, and for the purposes, set forth.
6:A bracket (10) with projection (11) and opening (12) (or equivalent.
base (11),
-or collar (21) and bracket (22)), as herein set forth and illustrated in
Figs. 5, 6, 7, 8, 11, 12 and 13 of the accompanying drawings.
"
"
7: A flow-and-return tube of the form shewn in Fig. 16 of the accom-
panying drawings, with end projection (8), and lateral openings in its return
half, or passage, as and for the purposes set forth.
"
8: A "flow-and-return tube of the form shewn in Fig. 17 of the accom-
4

page_text: panying drawings, with end projection (S) and lateral openings in the return
passage, as and for the purposes set forth.
9: A flow-and-return" tube formed to engage with fire-proof block, or
bearer, at one end, fitted with metal sleeve adapted to receive fire-proof covering,
and said tube supported at its front end by a further metal sleeve, substantially
as herein set forth, and illustrated in Figs. 18, 19, 20, 21, 22 and 35 of the accom-
panying drawings.
10: A metal tube (37) (or "flow-and-return "tube) with dovetailed ribs, or
projections, and segmental fire-proof covering with dove-tail recesses, or vice-
versa, as, and for the purposes, set forth.
11: A "flow-and-return" tube with projections (28), in combination with a
metal support (30) formed with grooves (29), as, and for purposes, set forth, and
illustrated in Figs. 29 to 33 of the accompanying drawings.
12: The general arrangements and combinations of parts forming my new
or improved smoke consuming and fuel economising apparatus, substantially as
herein set forth, and illustrated on the accompanying drawings.
Dated this 14th day of September 1898.
WILLIAM GRIMSHAW STONES
By John G. Wilson & Co.,
55, Market Street, Manchester, Agents.