Improvements in Tubulous Steam Generators.
Year: 1894

page_text: Date of Application, 29th Mar., 1894
Complete Specification Left, 31st Oct., 1894-Accepted, 1st Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in Tubulous Steam Generators.
I, FREDERIC STRICKLAND, of Kingswear, in the County of South Devon,
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to steam generators of the water tube type and has for
its chief objects to attain greater efficiency especially in confined situations, and to
facilitate fixing of tubes, and sweeping of the smoke passages.
The boiler consists of three parallel cylindrical vessels, one upper one being a
steam and water drum or separator, the two lower ones arranged a suitable
distance at either side in the usual manner, being collectors and connected together
by one or more similar cross collectors.
According to my invention, instead of directly connecting the side collectors to
the drum by series of water tubes in the known manner I employ and use in
combination with each lower collector a series of vertical headers or water boxes
rising therefrom of suitable form and capacity, and I connect these by tubes to the
upper drum. The headers may be of cast metal and are preferably of rectangular
forin (in plan). They are for the first part in contact with each other longitudinally,
thus forming a practically continuous water wall; they are fixed in open
communication with the collectors by suitably shaped corresponding screwed
nozzles formed upon each and adapted for connection by a collar. The inner flat
faces of the said vertical headers on either side of the boiler are connected by a
series of suitably disposed and more or less S-shaped tubes of small diameter to
the sides of the steam and water spaces of the upper drum; thus I am enabled to
obtain the advantages of larger water spaces, increased heating surface, and flat
tube plates. For fixing and cleaning tubes the back plates may be removable or
provided with opposite screwed plugs. The fire grate may be entirely enclosed
by the headers and tubes and the back end may consist of a water wall of vertical
tubes or similar headers in contact and fixed to a cross collector and to the drum
or a part in connection therewith, or it may be of firebrick. The whole is
enclosed in a suitable casing and the return circulating tubes between drum and
collector or collectors are arranged exterior to the tubes and header or casing.
The connecting tubes may be arranged in vertical planes whereby the products of
combustion will ascend direct to the uptake; or where low headway is required
the lowest tier on each side may be bent in inclined planes over the furnace and
arranged in contact so as to constitute a complete and continuous water roof
thereto for a suitable distance, combustion chambers or uptake passages being
formed at the back and where required by omitting certain or alternate tubes,
the upper ends of all the tubes being fixed to the drum.
By this means the smoke is compelled to take a circular course to the uptake
which may be arranged either at end or top of boiler casing as most convenient.
In small or launch boilers I may completely form the fire box of small tubes
connecting the collectors and drum and arranged in contact and bent over at their
upper parts so as to form the crown, and in such case 1 commence the side headers
and the connecting tubes at or about the bridge and continue same to back end
and forming also the back if desired, though this may be of firebrick. The planes
of the tubes and their peculiar bending are adapted to suit individual circum.-
stances, but in all cases I employ the vertical rising headers arranged upon the

page_text: whole or any part of the length of the side collectors and having flat tube plates
connected by suitably disposed serpentine tubes to the upper drum.
Dated this 29th day of March 1894.
J. C. CHAPMAN, C.P.A.,
Agent.
F
.
COMPLETE SPECIFICATION.
Improvements in Tubulous Steam Generators.
I, FREDERIC STRICKLAND, of Kingswear, in the County of South Devon,
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 steam generators of the water tube type and has for its
chief objects to attain greater efficiency especially in confined situations, and to
facilitate fixing of tubes and sweeping of the smoke passages.
I will fully describe my invention in reference to the annexed drawings, in all
the figures of which similar letters of reference indicate similar parts.
66
In Sheet 1 I have illustrated one form of my improved boiler which I will call
type A"; in Sheet 2 "type B" is illustrated; and Sheet 3 shows "
type C."
Referring to Sheet 1, Fig. 1 is to the left a side elevation with casing removed,
and to the right a longitudinal section on centre line;
Fig. 2 is to the left an internal elevation of back, and to the right a cross-section
on line 1-1 of Fig. 1.
The boiler consists of three parallel cylindrical vessels, one upper one D being
a steam and water drum or separator, the two lower ones C. C..arranged a suitable
distance at either side of the centre line in the usual manner being collectors and
connected together by one or more similar cross collectors C¹.
According to my invention, instead of directly connecting the side collectors CC
to the drum D by series of water tubes in the known manner, I employ and use in
combination with each lower collector C a series of vertical headers or water
boxes H rising therefrom of suitable form and capacity, and I connect the inner
sides of these by tubes T to the upper drum D. The headers H may be of cast
metal and are preferably of rectangular form (in plan). They are arranged so as
to be practically in contact with each other longitudinally, thus forming a
practically continuous water wall; they are fixed in open communication with the
collectors C by suitably shaped and corresponding screwed nozzles N formed upon
each and adapted for connection by a screwed collar n, as in Fig. 2. The inner
flat faces of the said vertical headers H on either side of the boiler are connected
by a series of suitably disposed sinuous and more or less S-shaped tubes T such
as are shown of small diameter to the sides of the steam and water spaces of the
upper drum D; thus I am enabled to obtain the advantages of larger water spaces,
increased heating surface, and flat tube plates. For fixing and cleaning tubes T
the back plates of the headers H may be removable, or provided as shown with
screwed plugs p. p. opposite each tube. The fire grate G is entirely enclosed by
the headers H and tubes T, and the back end may consist of a water wall of
vertical tubes or similar headers H₁ as illustrated in contact with other and fixed
as described to a cross collector C¹ and to the drum D, as shown in Fig. 2, or a
part in connection therewith; or the back wall may be of fire-brick or of both
tubes and fire-brick. The whole is enclosed in a suitable casing E lined where
desired with silicate cotton or other refractory and bad heat conducting material
as at e. e. The return circulating tube or tubes R between drum D and lower
collector or collectors is or are arranged in any convenient manner such as is
illustrated, and outside the casing E. In this type the connecting tubes T are
arranged as shown in vertical planes by which arrangement the products of com-

page_text: bustion will ascend in the direction of the arrows direct to the uptake U which
may be arranged on top of the casing as shown or at either end. Convenient
doors such as . d. are or may be provided in the casing E for cleaning and access;
represents a lining of refractory material around the furnace or where required,.
and S is the main steam pipe in the drum D. This type of boiler is particularly
well adapted for confined situations where height is limited.
In " type B" the above described arrangement is slightly modified chiefly in
regard to the disposition of the tubes T, the other parts described remaining sub-
stantially the same. In Sheet 2, Fig. 3 is a longitudinal section on line 1-1 of
Fig. 4 which is to the left a half-section on line 2-2 and to the right a half-section
on line 3-3 of Fig. 3. This type is designed especially for situations where low
headway is required, and for this purpose the lower tier t of side tubes T on each
side are bent in inclined planes transversely over the furnace Gas shown in Fig. 4,
and arranged in contact one with another in the longitudinal direction of the
boiler, as shown in Fig. 3, so as to constitute a complete and continuous water roof
and walls to the furnace for any suitable distance, for example, to just beyond the
fire bridge. Combustion chambers or uptake passages A are formed at the back
end by omitting certain or alternate tubes T, and thus the furnace gases being
deflected by the solid back wall are compelled to pass up in the direction of the
arrows and return along the top sides of the lower tube wall t and among the
superposed tubes to the front end. The uppermost row t¹ of tubes T T is also
arranged in contact to conserve heat and prevent escape of gases, and the uptake
may either be arranged vertically on the boiler as shown, access thereto for the
gases being provided for by omitting certain tubes beneath it at A', or the uptake
may be arranged with a smoke box at the front end of the boiler as shown dotted,
in which case the drum D may be extended. as dotted at D' whereby greater
heating surface is secured. The back end is formed either of continuous headers H'
communicating with the cross collector C¹ and the drum D and backed with
refractory material as illustrated, or of fire brick as may be found necessary, and
the arrangement of water box h with plugs * connecting the top ends of the
outermost headers H¹, illustrated in Fig. 4, is found to be convenient and efficient.
It will be observed that in the arrangements above described the vertical
headers H which form an essential feature of my invention have been disposed
along the whole length of the side receivers C C, but this is not always convenient,
especially in smaller or launch boilers, for which reasons I have modified my
invention and the modification is shown in Sheet 3, wherein Fig. 5 is to the left a
side elevation with casing removed, and to the right a longitudinal section on
centre line. Fig. 6 is to the right a cross-section on line 1-1, and to the left a
cross-section on line 2-2 of Fig. 5. Here the fire-box is completely formed of
small tubes T T connecting the collectors C C and the drum D, and arranged in
contact and bent over at the upper parts so as to form the haunches of the fire-
box crown at either side of the drum. In this case I commence the side
headers H at or about the bridge and continue same to back end forming also the
back if desired, though this may be of fire-brick. The furnace gases pass directly
up amongst the tubes to the uptake U which may be arranged upon the casing ĺ
as shown, or with a smoke box externally thereof at one end as shown dotted
at U in Fig. 5. The remaining detail is arranged as illustrated and as herein-
above set forth. In all these arrangements the planes of the tubes T and their
peculiar bending are adapted. to suit individual circumstances, but in all cases [
employ the vertical rising headers H arranged upon the whole or any part of the
length of the side collectors C and having flat tube plates connected by suitably
disposed serpentine tubes T to the upper drum D.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
:-
1. In a tubulous steam generator such as is above referred to, the use in com-

page_text: bination with the lower side collectors C C of vertical headers or water boxes such
as H H fixed thereon in open communication therewith and extending for the
whole or any part of the length thereof and connected to an upper drum or
receiver D by sinuous water tubes such as T T substantially as and for the purposes
above set forth.
2. The arrangement of the vertical headers H with flat front tube plates and
removable back plates or screw plugs opposite each tube end in combination with
the several receivers and tubes substantially as set forth.
3. The several arrangements of my improved tubulous steam generators sub-
stantially as above set forth and illustrated separately and respectively in
Sheets 1, 2, and 3 of the drawings.
Dated this 31st day of October 1894.
For the Applicant,
J. C. CHAPMAN,
70, Chancery Lane, London, W.C., Chartered Patent Agent.