Improvements in Sectional Steam Boilers.
Year: 1889

page_text: Date of Application, 26th Nov., 1889-Accepted, 28th Dec., 1889
COMPLETE
SPECIFICATION.
Improvements in Sectional Steam Boilers.
[Communicated from abroad by THE BABCOCK & WILCOX COMPANY, of New York
City, in the United States of America, Steam Boiler Manufacturers.]
1, WALLACE FAIRWEATHER, C.E., of 62 Saint Vincent Street, in the City of
Glasgow, Registered Patent Agent and Fellow of the Institute of Patent Agents do
hereby declare the nature of this invention and in what manner the same is to
be performed, as communicated to me to be particularly described and ascertained
in and by the following statement :-
This invention has for its object the adaptation of the construction of water tube
boilers to sustaining high degrees of pressure.
The entire structure composed of wrought metal tubes, either cylindrical or
pressed by dies into such various forms other than cylindrical as may be required for
such parts for instance as the serpentine tube headers, hereinafter referred to; or
the manifold connecting the said tube headers with the receiving drum; and the
invention consists in certain novel features of construction whereby essential parts are
reduced in size and assembled in a manner that will permit the necessary expansion
incident to the high pressure used without racking the joints between such parts;
and whereby the strains brought upon the joints are sub-divided and shared by a
plurality of parts. The invention also consists of certain improved constructions
relating to the joints themselves that connect the receiving drums above the tubes with
the tube headers or with the manifold intermediate between the tube headers and the
drum;
and in order to enable others skilled in the art to which my invention
appertains to understand and construct the same, I will proceed to describe the
features thereof in detail with reference to the accompanying drawings, in which
like letters of reference indicate corresponding parts throughout and, in which;
Figure 1, is a sectional elevation taken lengthwise of the boiler through the
foundations on the line ax of Figures 4.
Figure 2, an enlarged detail view of the connecting joint employed for connecting
the receiving drum with the manifold in Figure 1.
Figure 3, a modification of Figure 2.
line --
--
--
Figure 4, a front elevation partly in cross-section on the line y y of Figure 1.
Figure 5 a rear cross-sectional elevation on line z z of Figure 1.
Figure 6, a sectional elevation taken longitudinally of the boiler in the plain of the
x, Figure 7, showing a modification of the invention; and
Figure 7, a front elevation partly in cross-section on the line y y of Figure 6.j
A, A, Figure 1, are the successive series of inclined water tubes, their positions as
appearing in cross-section in Figure 4 being staggered vertically, whereby the tubes
of one horizontal cross-series lie vertically opposite the intervening spaces of adjacent
series above or beneath them in the manner common in water tube boilers-The
tubes are placed in the ordinary inclined position, highest at the front, and lowest at
the back with the furnace B, of any usual or suitable general construction under-
neath the front or elevated end. The hot products of combustion pass between the
staggered tubes A, above and beneath the respective bridge block partitions M', M',
thence to the exit N.
The vertical headers C, C, correspondingly connect the staggered tubes at the
front and rear ends of the structure in single vertical series, whereby a single tube of
each horizontal cross series has communication with an individual header; the ends
of the tubes being expanded into the headers in the usual manner to connect with the
interiors thereof; and in order to correspond with the staggered position of the tubes
the headers are of the usual serpentine form having alternately staggered openings to
receive the tubes-I prefer to employ headers C, C, that are constructed of wrought
Price 17

page_text: metal pressed by means of sectional dies from straight polygonal tubes into the cor-
rugated form by a process heretofore described in the Specifications of Letters
Patent granted to me and numbered 3038 of 1886, 5887 of 1886, 8229 of 1887,
and 11,789 of 1887.
D, D, etc. are the receiving drums corresponding with the usual steam drums of a
sectional steam boiler, adapted to receive the superheated water delivered from the
upper ends of the inclined water tubes through a manifold or connecting box F; the
current of circulation passing thence rearwardly through the parallel drums, and
downward through the downtake pipes E, to the rear tube headers C-For the purposes,
of the present invention, the drums D. are preferably constructed of wrought metal
tubing of the necessary diameter, and their terminations are formed by a reduction of
size or necked formation at their ends, which ends are flanged to receive a suitable
cap, as O, at the front as in Figure 6, or a pipe connection as shown at the rear ends in
Figures 1 and 6, or the reduced ends may be screw-threaded to receive separate
flanges as in Figures 2 and 3, and as more particularly hereinafter described-Other-
wise the tubular drums may be left of full diameter at the ends and fitted with
separate flanged heads welded into them.
The manifold F, is constructed of cylindrical tubing extending transversely the
width of the structure, which may also be terminated by a reduction at the ends to
receive a small cap, but is preferably terminated by concave flanged heads a, appearing
in dotted lines in Figure 4, over the margins of which the ends of the tube are
reduced and welded as indicated-The manifold F, may be also made in polygonal
form in cross section instead of cylindrical as indicated at F1, in Figures 6
and 7.
The upper ends of the front headers C, are severally connected with the mani-
fold or connecting box F, or F1 by suitable expanded nipples or short tubes at b,
and the said connecting box in the instance of F, is connected by similar expanded
nipples or short tubes G¹, to each of the overhanging receiving drums D.
As illustrated in Figures 1 to 4 inclusive, in which the connecting box F, is placed
on a level with the ends of the receiving drum D, the connection is made between said
connecting box F, and receiving drum D, by the novel construction of the joint
illustrated in detail by Figures 2 and 3-In Figure 2, the reduced or necked portion
of the drum D, is screw threaded on its exterior to receive a flange I, through which
the several stay bolts J, extend from the shell F, and retain the parts together in a
rigid position with relation one to another-G, is a connecting nipple or short tube
that is expanded into the shell F, and into the reduced end of the drum-The
nipple G, is also screw threaded on its exterior to receive a flange H; and through
this flange H, the stay bolts J, also extend. The stay bolts J, are provided with jamb
nuts that secure them into the sides of the shell F, the said bolts having bevelled
washers 9. to provide a suitable seat for the nuts f, where the bolts intersect inclined
portions of the cylindric shell as shown-The stay bolts J, are also provided with jamb.
nuts e that secure the flange H, of the nipple, and the flange 1 of the druni to them,
and with proper relation to each other.
In Figure 3, the reduced or necked portion of the drum D, is screw threaded on its
exterior in a similar manner, and for a similar purpose as in Figure 2-The separate
nipple G, is however dispensed with and a continued portion of the drum neck that is
reduced in thickness is left in its stead the same being expanded into the shell F by a
suitable expanding tool-The stay bolts J, are similarly employed as in Figure 2 to
clamp up and stay the flange I-In Figure 3, I also show a modified feature of the.
shell F, consisting in flattening its side at that portion of its surface intersected by.
the drum neck and its connecting bolts-Such a feature is equally applicable to the
construction in Figure 2-The bolts J, in both modifications, may be employed in any
desired number, and they serve to rigidly hold the connected parts in a fixed relation,
both longitudinally and laterally for the purpose of insuring against racking of the
joints or any degree of displacement of the expanded surfaces of the metal.
At the opposite ends of the drums, the tubes E are adapted to yield to the differences
of expansion between the drums and the water tubes A, and to this purpose the said

page_text: tubes E are made of a spiral curvilinear form; such form serving also the purpose of
connecting each drum with a plurality of the headers C, as illustrated by the rear
elevation Figure 5-The ends of the tubes E, are expanded into the metal of the
drums, but to ensure firmness of the joint so formed, there is also a wrought iron
ring K, that is secured by being shrunk on the drum after being heated, and that
affords an increased thickness of the metal into which the tube is expanded, and an
extended surface therefor which holds the tube rigidly. A similar shrunk collar as K'
may also be similarly employed upon the drum D, to receive the connecting nipples
or tubes between the same, and the manifold Fi, in Figure 6, as illustrated. The
wrought iron ring or collar K, also has for its function to reinforce the shell of the
drum at those points that would otherwise be weakened by the perforations.
In the illustration of Figure 6, I have also shown the adaptability to the invention
of downtake pipes E', of prolonged length, in lieu of the curved pipes E of less
length, the said pipes E', being employed in series, transversely corresponding with
each drum D, and connected therewith and directly to the mud drum beneath the
lower extremities of the rear tube headers C-The vertical elongation thereby
attained in the vertical downtake pipes E¹ promotes a suppleness of the connection
that is equivalent to that obtained by the curvilinear form given to the short pipes E
of Figure 1; and the differences of linear expansion between the water tubes A and
the drums D, will not materially affect the joints of the pipes E', within the collar K,
and within the openings of the mud drum.
L is a steam expansion drum used in connection with the receiving drums D, in
the practice of water superheating; incident to which practice, the water level is above
the drums D, as at j, Figure 4, in the vertical pipes and variation in the expansion
of the water due to an increase or decrease of temperature is permitted without great
fluctuation of pressure by the elasticity of the steam space in said expansion drum.
The expansion drum L, may be of any suitable construction, but as represented
is of similar form and construction to that of the connecting box F in Figures
1 and 4.
It will be observed that as shown in Figure 7, the feature of employing shrunk
reinforcing rings K2, is likewise applicable for receiving the expanded ends of
connecting tubes connecting with the expansion drum L.
M, are the delivery pipes employed to conduct the superheated water to the places
where it is used for steam generation or other suitable purposes.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, as communicated to
me, I declare that what I claim is :-
1. In a water tube boiler, the combination with its cross series of vertical headers
that connect adjacent ends of the water tubes, and the cross series of longitudinal
receiving drums above said water tubes, of a transverse separate connecting box that
communicates intermediately with said headers and said drums by means of
independent tubes projected severally from the headers, and severally from the drums
into said connecting box substantially as described.
2. In a water tube boiler the combination of a receiving drum terminated by a
necked end; a transverse connecting box connected to said receiving drum by the
expansion of its necked end in the manner described into an aperture of said
connecting box through which communication is established between the latter and
the said drum; a flange secured to the exterior of the drum neck; and the stay bolts
extending between said flange and portions of the connecting box opposite thereto
about the said aperture, adapted to stay the said parts relatively to each other for the
purposes described.
3. In a water tube boiler, the combination of a receiving drum terminated by a
necked end; a transverse connecting box opposite said necked end; a connecting
nipple or tube expanded at one end into the said necked end of the drum and at
its opposite end into an aperture of the connecting box by which communication is
established between the latter and the said drum, flanges secured to the exterior of the

page_text: drum neck and to the exterior of the nipple or tube, and the stay bolts extending
through and connected with said flanges and to portions of the connecting box opposite
thereto about said aperture, adapted to stay the said parts relatively to each other for
the purposes set forth.
4. In a water tube boiler the herein described receiving drum necked at its end to
join with a connecting box; the neck of said drum having a thicker portion that is
exteriorly screw threaded to receive a flange by which the joint is stayed as described,
said neck also having a thinner portion that is extended beyond its thicker portion,
and adapted to be inserted and expanded into an aperture of said connecting box by
which communication is established between the latter and the drum.
5. In a water tube boiler, the combination with a cross series of vertical beaders
connecting adjacent ends of the water tubes; a cross series of longitudinal receiving
drums above said water tubes and the headers, and the herein described curvilinear
down take pipes adapted to connect a plurality of said headers with a single of said
drums and to promote a yielding connection between the same as set forth.
6. In a water tube boiler the combination with a seamless drum cylinder of a
reinforcing ring shrunk upon the exterior of said cylinder, adapted to give an
increased bearing surface to a tube intersecting said cylinder and said reinforcing ring
expanded therein to form a joint.
Dated this Twenty-fifth day of November 1889.
CRUIKSHANK & FAIRWEATHER,
62, Saint Vincent Street, Glasgow, Agents.