Improvements in Water Tube Steam Generators.
Year: 1896

page_text: Date of Application, 4th Nov., 1896-Accepted, 23rd Jan., 1897
[Communicated from abroad by THE BABCOCK AND WILCOX COMPANY, of New
York, in the United States of America, Steam Boiler Manufacturers.]
Improvements in Water Tube Steam Generators.
1, WALLACE FAIRWEATHER, C.E., of 62 Saint Vincent Street, in the County
of the City of Glasgow, Chartered Patent Agent, 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:-
The improvements hereinafter described are particularly adapted to marine
boilers, though they are applicable to boilers for land-service as well. The
improvements consist in certain novel features of construction and arrangement,
which will be described in the specification and pointed out in the claims.
In the accompanying drawings,
Figure 1, represents a front view of the boiler with a part of the casing and the
hand-hole covers of the water-tubes removed, the euds of the steam-and-water
drum being within the side-casing of the boiler.
Figure 2 shows a horizontal section through a portion of the same, on line 2-2
of Fig. 1.
Figure 3 represents a vertical section, on line 3-3 of Fig. 1, showing a side
view of the stacks of tubes and their headers, with certain parts in section.
Figure 4 shows a vertical, transverse section of a portion of the siding of the boiler,
on line 4-4 of Fig. 3.
Figure 5 represents, on a larger scale, a vertical, transverse section of a portion
of such siding.
Figure 6 represents a rear view of the lower part of one of the corner columns,
and a part of the mud-box or drum, in its anchor-plate.
Figure 7 represents a vertical section, on line 7-7 of Fig. 1, showing, in
elevation, the side-tubes of the boiler and the two corner columns with which they
are connected, the steam-and-water drum and upper boxes being in transverse
section.
Figure 8 represents a vertical section, on line 8-8 of Fig. 6.
Figure 9 shows a vertical section through a lower portion of one of the rear
corner columns, on a larger scale.
Figure 10 represents a top view of the steam-and-water drum and its pipe
connections with the box that surmounts the front headers, the ends of the drum
being within the side-casings of the boiler.
Figure 11 represents a front view of the boiler with certain variations in
construction, a part of the casing being removed.
Figure 12 shows a vertical section of the same, on line 12-12 of Fig. 11.
Figure 13 represents a vertical section of a portion of the siding of this boiler,
on line 13-13 of Fig. 12.
Figure 14, represents, on a larger scale, a vertical transverse section of the lower
portion of such siding, the non-conducting filling between the side-tubes being
differently constructed.
Figure 15, shows, on an enlarged scale, a transverse section of the steam-and-
water drum, on line 15-15 of Fig. 16, representing an improved form of

page_text: Figure 16, represents a side view of a portion of the drum.
Figure 17, shows a transverse section of a part of the drum, on line 17-17 of
Fig. 16.
Figure 18, represents, on a smaller scale, a transverse section of a steam-and-
water drum of a well-known construction.
Figure 19, represents, in transverse section, a portion of the steam-and-water
drum, and in side view a portion of a rear-header of the boiler, the connection
between the drum and the header being modified.
Figure 20, shows a rear view of a portion of such drum.
Figure 21 represents, in transverse section, a portion of the steam-and-water
drum, and in side view a portion of a rear-header, the connections between the
drum and headers being upright ones.
Figure 22, shows a rear view of such portion of the drum, headers and
connections.
Figure 23 represents, on an enlarged scale, a vertical, transverse section of the
siding and the side tubes of the boiler, the siding being of improved construction.
Figure 24 shows, on a still larger scale, a vertical transverse section through a
part of the inner sheeting of the siding and the serpentine filling-board riveted
thereto.
Figure 25 represents a front view of a boiler with a part of the casing and the
hand-hole covers of the boiler-tubes removed, in which two furnaces are shown,
both sides of each of which are composed of water-tubes.
Figure 26 shows a vertical, longitudinal section of such boiler, on line 27-27 of
Fig. 25.
The boiler shown in the drawings is of that class known as a sectional boiler,
which is composed of a stack or stacks of steam-generating tubes, A, Fig. 3,
slightly inclined upwardly from rear to front, and their respective ends connected to
headers, a a', that are connected to the steam-and-water drum, A'. The boiler
shown is, also, of the marine type, with which no exterior masonry setting is
employed, but the sides are composed of water conduits or tubes, in circulatory
connection with the drum, which conduits or tubes furnish additional steam-making
capacity.
a
One feature of the invention relates to the means employed in securing
circulation through these side-conduits or tubes, which construction also enables
the boiler to be hung up or suspended and provides for the longitudinal expansion
of the tubes.
In Fig. 7 of the drawings the conduits upon one side of the boiler are shown,
the same being adapted to the boiler shown in Fig. 3, and being in the form
of tubes, B B, which are connected at their ends to upright, hollow-water-
columns, CC, the series of tubes on the other side being similarly connected, so
that four corner columus are employed, two (C C) at the front and two (C¹ C¹) at
the rear.
On the front and rear faces, the columns are respectively provided
with holes, c, see Fig. 9, in alignment with the tubes, which are normally closed by
hand-hole covers, c..
Extending transversely of the boiler, on the front, is a box, a³, and a similar
box a', extends transversely of the same at the rear, the said boxes being nippled
or connected near their ends to the upright columns, CC, C¹ C', respectively,
which columns the ends of the boxes overlie. The box, a', is connected with the
drum, A', by pipes, a', and the box, a³, is connected with the drum by pipes, a', so
that the circulation of water from the drum into the tubes B B', is down through
the pipes, a, into the box a', thence into the rear columns, C C¹, and into the
tubes while the steam from the tubes passes up through the front columns, CC,
into the box a³, and thence through the pipes, a', into the drum.
The columns, C C¹, are securely attached at their lower ends by bolts, or
otherwise, as shown at a, Figs. 3, 7 and 9, to a base-iron or frame, C; and as
shown in Figs. 1 and 3, the headers, a a', are nippled or connected to the
boxes, aa, respectively, so that the said columns and boxes support the headers

page_text: and tubes, the same being suspended by the nipple connections to the boxes and
columns, thereby providing for the longitudinal expansion of the tubes. Preferably,
a mud-box or drum, D, is employed in connection with the boiler, and the rear
lower end of the latter is anchored by irons, such as d, which fork the box and hold
the rear end of the boiler in a fixed position, as shown in Figs. 3, 6 and 8, so that
the expansion of the tubes thereof is wholly toward the front. If desired,
however, the rear transverse box, as, may be dispensed with, as shown in Fig. 12,
and the pipes, a, connect the rear headers directly with the drum, A', such
headers resting upon the rear wall, e, of the furnace, E, while the front of the
boiler is suspended by the transverse box, a', upon the front columns, C C.
Another feature of the invention consists in making the lower side tubes, B¹, in
the form of boxes having flat, smooth inner faces which form the sides of the
furnace, E, and enable a fire-brick lining on such sides to be dispensed with. As
shown in Fig. 4, these tubes are rectangular in cross-section, and as shown in
Figs. 3 and 7 are placed one above the other in close proximity, and they are
inclined upward from rear to front, so that no steam-pockets can be formed
therein.
To furnish still greater facility for the outlet of the steam formed therein, the
boxes may be made larger at the front than at the rear ends, or frustro-pyramidal
in form, as shown in Fig. 12. Those faces of these boxes that are toward the fire
are flat and smooth, so that they furnish no obstruction to a convenient use of fire
tools, and no interstices or spaces for the lodgment of ashes, as they would were
such boxes in the form of round pipes, in which case V-shape crevices would be
present in which the tools would catch and refuse from the fire collect. These
boxes have all the advantages of water-legs on the sides of the furnace, and having
no interior lateral stays between their sides to impede the circulation of water,
they are superior to a water-leg made continuous, or of two parallel, cross-stayed
sheets, not only because circulation is not disturbed, but because repairs to the
sides of the furnace can be much more easily, quickly and inexpensively made.
owing to the sectional character of the improved furnace-siding.
In order further to increase the steam-making capacity of the boiler, provision
is made at the front thereof, below the headers, for a circulation of water around
the furnace doorways. As shown in Fig. 1, a transverse box, F, is connected at
its ends to the two front, corner columns, C, and to it are nippled arch-shape
boxes G, which fork the doorways and are connected at their tops, by one or more
pipes, g, to the front headers, a. Between these arches, also, pipes, g³, may extend
from the box, F, to the headers above. In place, however, of employing these
arch-shape boxes, the construction may be such as shown in Fig. 11, where two
transverse boxes, F F', are used, which are connected by pipes, G₁, extending
between these boxes, on each side of the doorways, the pipes, gl, also connecting
said boxes, and the upper box being connected by pipes, g, to the headers.
and 11.
In the boilers represented in Figs. 1 and 11, the three furnaces, E, have the
sidings composed of the water-tubes, B', arranged only on the outsides of the
boiler, none being located between the furnaces. As shown in Figs. 25 and 26,
however, a water-tube furnace-siding may be located between two adjacent
furnaces, so that each furnace will be distinct from its neighbours and one furnace
alone can be run with greater economy than in the arrangement shown in Figs. 1
With this construction, the intermediate water-tubes, B', have their ends
connected so as to provide a circulation therethrough, as to short, upright
headers, C, C, located at the front and rear of the boiler, respectively, the
header, C' being connected at its top, as by a pipe b, to one of the boiler-headers, a,
and at its lower end to the transverse box, F, while the header, C2, is connected at
its top to one of the rear headers, a', and at the bottom to the box, D. If the
box, F, shown in Fig. 11, be employed, however, the top of the header C², may
be connected thereto instead of to a boiler header, as will be readily understood.
The exterior siding, H, of the boiler is of improved. construction, and is shown
in Figs. 4, 5 and 13 as composed of an outer sheet, h, of metal, an inner sheet, h',

page_text: and an intermediate filling, 7, of non-heat conducting material, such as asbestos
boarding and magnesia filling, the siding being arranged in close proximity to the
tubes, B B, and properly secured in position. To increase the thickness of this
siding, and at the same time to fill the spaces between the pipes, B, so that but
little ashes or soot can lodge on the upper surfaces of said pipes, blocks or filling-
pieces,, of asbestos or other suitable non-heat conducting material are located
between said pipes. These blocks are preferably hard packed, and are held in
place by making their rear portions of greater width than their front portions, as
clearly shown in Fig. 5. Substantially the same result may be secured, however,
by forming asbestos board, or similar material, A, in serpentine shape, between the
sheet, h, and the pipes, B, as shown in Fig. 14.
A preferred form of construction, when such serpentine board is usel, is shown
in Fig. 23, where the inner sheet, A', is made in pieces or sections (two, 30, 30 of
which are represented, being butt-jointed together at 31), and the intermediate
filling, h, is formed in block, 32, the joints of which break with those of the inner
sections, 30. The serpentine inner lining, *, is also shown as made in sections, 33,
which are secured to the sheet, ', by rivets, 34. The spaces, 35, between the
sheet, h, and lining, A, may be filled with blocks similar to those designated as h³
in Fig. 5, or mineral wool or other non-heat-conducting material may be packed
therein. In constructing this siding, the sections, 33, of the lining, h, with the
rivets therein, are placed against the side tubes, B; the packing in the spaces, 35,
is inserted; the sections, 30, of the sheet, h, are applied and riveted to the
sections, 33; the blocks, 32, composing the filling, h, are put in place; and the
outer metal sheet, h is secured in position.
The front of the boiler, between the box, F, and the lower ends of the headers, a,
is also preferably filled in with non-heat-conducting blocks, f, of asbestos or other
suitable material, as shown in Figs. 2, 3 and 12.
As ordinarily constructed, the rear furnace-wall, e, underlies the rear headers of
the boiler, and is beveled or rounded on its front upper corner, as shown in
Fig. 12, so that ashes, &c., may not lodge thereon. It is sometimes the case,
however, that with a definite length of boiler a shorter grate is desired, and if this
wall retained the position described, its thickness would have to be greatly
increased, and the bevel be so slight that the ashes, &c., would collect on its top,
and bank around the lower boiler-tubes, to their detriment. In Fig. 3, a construc-
tion is shown which avoids both of these features, the improvement consisting in
setting the rear wall, e, forward, and at the end of the short grate, thereby leaving
a space, e¹, behind the wall into which the ashes can fall, and be removed through
a door, e, upon the rear casing of the boiler. The suspension of the boiler, as
herein before described, enables this to be done, as the rear wall, in such case, is
not necessary as a support for the rear headers.
Another feature of the construction shown relates to the steam-and-water drum,
whereby the same is enabled to be made a perfect circle in cross-section, and is
strengthened at the parts where it is perforated to receive the connecting pipes.
Heretofore a drum has been constructed in which sheets have been used of a
width equal to the circumference of the drum plus the width of the lapped sides of
the sheets, as shown in Fig. 18, the said sheets being riveted together at their
ends to produce the necessary length of drum; and the drum has been perforated
at the lap to receive one set of pipes, the perforations for the other set of pipes
being made through a single thickness of the sheets at the proper place. Such a
drum is not only comparatively expensive, owing to the higher cost of such extra
wide sheets which are difficult to obtain, but it is somewhat imperfect because it is
not truly circular in cross-section-the steam tending to force it into such true
form, thereby producing an undue strain thereon.
The improved construction of drum is shown in Figs. 15, 16 and 17. In its
manufacture, two sheets, are employed to make up its circumference, one of
them, K, being of a width to make the upper portion of the circumference, and the
other, of a width to make the lower portion thereof, the butt joint edges of
K',

page_text: the sheets coming together in lines passing substantially through the centres of
the pipes a, and as, respectively. These sheets are formed so that they make a
true circle when placed together, and being of widths which are easily and
commonly manufactured are comparatively inexpensive. They are secured to
each other by straps, k, k, and rivets, k2, the straps preferably being applied both.
interiorly and exteriorly, and the sheets are riveted together end to end to form
the length of the drum. As the perforations to receive the pipes, a, a, are made
at the butt-joints of the sheets and through the straps, k k¹ the drum is perforated
at its strongest parts, thereby securing the greatest strength possible.
In Figures 3, 7, 12 and 15, the rear portion of the boiler is shown as connected.
to the drum by pipes, as, which are curved, and are, therefore, comparatively
expensive to make of wrought iron. In order that straight pipes may be used for
such connections, and right-angle joints be made between such pipes and the drum,
I have changed the form of the drum, as shown in Figures 19, 20, 21 and 22. In
Fig. 19, the pipe, a', is shown as straight and as projecting from the inner face of
the header, a'. To receive the series of these pipes with right-angle joints, the
exterior strap,, is embossed so as to provide it with a series of pockets, k³, the
faces, k, of which will stand at right angles to the longitudinal axes of the pipes, as,
the said faces being perforated to receive the pipes, as shown in Fig. 20. The
portions, k, of the strap between the pockets, k, are left on the same curve as the
drum, so as closely to hug and re-enforce the same, and the pockets communicate
with the drum through perforations, a.
In Figs. 21 and 22, the pipes, a, are straight, but project from the tops of the
headers, a¹. The strap k¹, is embossed to form the pockets, k, the faces, k, of
which stand at right angles to the longitudinal axes of and are perforated to
receive the pipes, a', the portions, k, of the strap hugging the drum as just
described.
A boiler supplied with a feed water heater is shown in Fig. 11. The two parts
of the heater are denoted by L L', and each consists of a series of pipes, l, the ends
of which are joined together, as by boxes, ', in a common manner, as shown in
Fig. 12. The part, L, is provided with an inlet, M, having a valve, (not shown)
and the part, L, with an inlet M', having a valve m', the said inlets being supplied
by a common pipe. The part, L, has an outlet, O, furnished with a valve, o, and
the part L', has an outlet O' provided with a valve o' such outlets discharging
through a pipe, P. When running normally, all these valves are open, so that
water passes through both halves of the heater; but should a leak or other damage
occur in either part of the heater, the valves of such part can be closed, leaving
the other part to supply the heated water until repairs have been made. The
expense of such a double heater is but slightly in excess of a single one, and its
utility is evident under the circumstances mentioned.
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. In a sectional steam generator of the type described, a transverse water-box
connected to upright columns which support said box and to the front headers and
drum by short tubes or nipples, whereby the boiler is suspended at the front to
said box and columus, substantially as specified.
2. In a sectional steam generator, a transverse water box located at the front of
the boiler and connected to the drum and to the front headers; a transverse
water-box connected to the drum and to the rear headers of the boiler, and to
front and rear upright columns respectively, by means of short tubes or nipples
which support said boxes and thereby suspend the whole boiler, substantially as
set forth.
3. A sectional steam generator comprising front aud rear upright water columns,
5 a series of water-tubes on each side of the boiler counected at their ends to said
columns, and a transverse water-box at the front of the boiler, nippled to the drum
с

page_text: and to the front water-columns, and having the front headers of the boiler nippled
thereto, substantially as specified.
4. A sectional steam generator of the type described, constructed with front and
rear upright water-columns; a series of water-tubes on each side of the boiler
having their ends connected to a front and a rear column respectively; a transverse
water-box connected to the drum, and to the front water-columns and having the
front headers of the boiler connected thereto; and a transverse water-box
connected to the drum and to the rear water-columns and having the rear headers
of the boiler connected thereto, substantially as specified.
5. A sectional steam generator having front and rear upright water-columns
which are connected with the drum; a series of water-tubes on each side of the
boiler connected at their ends to said columns, the lower tubes of the series having
flat inner faces which form the sides of the furnace; and a transverse water-box
connected to the drum, and to the front water-columns and to the front headers of
the boiler, substantially as set forth.
6. In a sectional steam generator, a series of water-tubes located on each side of
the boiler and connected at their front and rear ends to upright water-columns,
which are connected to the drum, the lower tubes of said series being inclined
upwardly from rear to front, having flat inner faces and forming the side-walls of
the furnace, substantially as set forth.
7. A sectional steam generator having a series of water-tubes located on each
side of the boiler and connected at their front and rear ends to upright water-
columns, which are connected to the drum, the lower tubes of said series being
inclined upwardly, having flat inner faces and forming the side-walls of the
furnace, substantially as set forth.
8. A sectional steam generator constructed with front and rear upright water-
columns which are connected with the drum; a series of water-tubes on each side
of the boiler connected at their ends to said columns; and a transverse water-box
located below the furnace doorway; connected at its ends to the front water-
columns; and an arch-shape water-conduit extending along the sides aud over the
top of said doorway, and connected to said box and to a front header of the boiler,
substantially as set forth.
9. In a steam-boiler having a series of water-tubes extending along each side of
the boiler, outlying the main tubes thereof and connected with the steam-and-water
drum, the combination of a siding composed of an outer metal sheet, an inner sheet,
and an intermediate filling of non-heat-conducting material; and blocks or filling
pieces of such material located within the siding and between said side tubes,
substantially as and for the purposes specified.
10. The combination, with a steam-boiler, of a siding composed of an outer
metal sheet, an inner sheet of non-heat-conducting material made up of sectional
parts, and an intermediate filling of non-heat-conducting material made up of
blocks which break joints with those of the inner sheet sections, substantially as
set forth.
11. The combination, with steam boiler, of a siding composed of an outer metal
sheet, an inner sheet of non-heat-conducting material made up of sectional parts:
an inner serpentine lining made up of sectional parts secured to the inner sheet;
and a filling of non-heat-conducting material between the outer and inner sheets,
substantially as set forth.
12. In a steam-boiler having a series of water-tubes extending along each side of
the boiler, outlying the main tubes thereof and connected with the steam-and-water
drums, the combination of a siding composed of an outer metal sheet, and inner
sheet of non-heat-conducting material; an intermediate filling of non-heat-
conducting material, an inner lining of serpentine form projecting inward between
said side-tubes, aud a packing of non-heat-conducting material located in the
spaces between the inner sheets and the inner lining, substantially as set forth.
13. In sectional steam generator, a series of water-tubes on each side of the
boiler connected at each end with the drum; a transverse water-box located below

page_text: the furnace doorway, connected at its ends with said side tubes, and to a front
header of the boiler by water-conduits extending up the sides of said doorway;
and a filling of non-heat-conducting material located between said box and the
front headers of the boiler, substantially as set forth.
Dated this 3rd day of November 1896.
WALLACE FAIRWEATHER,
62 Saint Vincent Street, Glasgow, Chartered Patent Agent.