IMPROVEMENTS IN STEAM GENERATORS GENERATOR
Year: 1871

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn
Fields, in the County of Middlesex, Gentleman, for the Invention
of "IMPROVEMENTS IN STEAM GENERATORS."-A communication from
abroad by Joseph Alexandre Westerman, of Paris, in the Republic of
Tunan
Tinginnan
Sealed the 7th May 1872, and dated the 18th December 1871.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of. Patents, with his Petition,
on the 18th December 1871.
I, JOHN, HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN, STEAM GENERATORS," a communication
to him from abroad by Joseph Alexandre Westerman, of Paris, in the
Republic of France, Engineer, to be, as follows :-
+
This 'Invention relates to a peculiar construction and arrangement of
tubular steam generators consisting of a number of ranges or tiers of
:'
2

page_text: water tubes placed horizontally, vertically, or at an inclination and
crossing each other at right angles or at any other convenient angle, the
ends of such tubes being screwed or otherwise secured to water chambers,
which are bolted together and serve to connect the several ranges of
tubes. These chambers when packed close together side by side form
the outer sides of the boiler; they communicate also at the top and
bottom of the boiler respectively with two large tubular chambers, the
upper one serving as a steam chamber and the lower one as a feed water
'chamber. These two chambers are connected by pipes so as to ensure
perfect and free circulation through the several tubes and water chambers.
A screwed plug is fitted into each water chamber opposite the tube con-
nected thereto to facilitate the cleaning of the same, and a small
projection inside the chamber opposite the centre of the tube serves, to
separate as much as possible the steam from the water.
The joints of the several water chambers are flanged joints with a
packing ring interposed of india-rubber or soft metal.
The grate bars are disposed beneath the ranges of tubes, and the
flames circulate freely round and amongst the same and finally pass
off to the chimney. The entire boiler is inclosed in an outer shell or
casing of sheet metal.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office on the 18th June 1872.
TO ALL, TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of a
Middlesex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent; bearing date the Eighteenth day of December, in the
year of our Lord One thousand eight hundred and seventy-one, in the
thirty-fifth year of Her reign, did; for Herself, Her heirs and
successors, give and grant unto me, the said John Henry Jolinson,
Her special license that I... the said John Henry Johnson, my
executors,. administrators, and assigns, or such others as I, the said

page_text: John Henry Johnson, my executors, administrators, or assigns, should
at any time agree with, and no others, from time to time and at
all times' thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United'
Kingdom of Great Britain and Ireland, the Channel Islands, and
Isle of Man, an Invention for "IMPROVEMENTS IN STEAM GENERATORS,” a
communication to me from abroad by Joseph Alexandre Westerman, of
Paris, in the Republic of France, upon the condition (amongst others)
that I, the said John Henry Johnson, my.executors or administrators,
by an instrument in writing under my hand and seal, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be
filed in the Great Seal Patent Office within six calendar months next
and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Henry Johnson, do hereby.
declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained.
in and by the following statement, reference being had to the accom-.
panying Drawings and to the letters and figures marked thereon, that is
to say :-
་
The said Invention consists in the arrangement of rows of tubes
composed of wrought or cast iron, copper, or other suitable material of
any diameter disposed either horizontally, vertically, or at an angle, and
containing the water to be vaporized. These rows of tubes are placed
one over the other and cross each other at right angles or at any other
suitable angle with greater or less intervals between them.
The extremities of the tubes open into cast-iron chambers, which
when they are placed in juxtaposition one against the other form the
internal sides of the furnace, the tubes being all enclosed in this furnace..
Large tubes composed of cast-iron or metal plates are disposed above
and below the assemblage of tubes, and serve as steam and feed water
reservoirs.
The fire-grate is situate directly beneath the rows of tubes so that the
flames pass into the intervals which exist between them, by which the
flames are considerably divided, the effect of which is to utilize as com-
pletely as possible the heat evolved from the fuel.
.

page_text: And in order that the said Invention may be fully understood 1 șhall,
now proceed more particularly to describe the same, and for that purpose
shall refer to the several Figures on the annexed Sheet of Drawings, the
same letters of reference, indicating, corresponding parts in all the
Figures:
Figure 1 is a vertical section of a steam generator constructed accord-
ing to this Invention, taken through the centre thereof; Figure 2 is a
horizontal section of the same taken along the line 1, 2 (Figure 1);
Figure 3 is an end view shewing the exterior of the assemblage of tubes;,
and Figures 4, 5, 6, and 7 are details of the caps or covers which close
the extremities of the tubes and establish a communication between
them..
1..1 F
This boiler is composed of series or rows of tubes a disposed horizon-
tally or at a slight inclination, as. shewn in the Drawing, so as to admit
of the ready, discharge of the steam. These rows of "tubes-cross each
other at right angles or at any other angle, and the extremities of the
tubes a open into hollow caps or covers; b, which are connected together,
and establish a 'communication between the tubes. These caps or covers
may each be provided with a screw plug (Figure 7), which is unscrewed
at will in order to clean the inside of the tubes, and with a division e
(Figure 7) when required, which serves to separate the steam from the
water as much as possible.
⚫. The boiler is completed by two large tubes B, A, which are situate
respectively above and below the assemblage of tubes. The lower
tube A, which is elbowed at right angles, serves as a feed water reservoir,
and the caps or covers 6 of the first two rows of tubes a come against
the tube A and form a communication between it and the said tubes.
The upper tube-B serves as a steam reservoir, and communicates, with
the upper row-of-tubes a through the caps or covers-b. Two tubes E are
also provided, which place the tube B in communication with the
tuberA:
The connection of tubes a with the hollow caps or covers 6 and the
mode of connecting the caps together are shewn in detail in Figures 4,
5,6, and 7. The caps or covers may be composed of cast iron,. copper,
or malleable cast iron. The tubes a are screwed therein or are connected
thereto in any other suitable manner. The caps.or covers are connected
together by the aid of a joint, which may be effected in various ways, as

page_text: for example either by inserting india-rubber or metal washers in.grooves
formed in each elbow pipe 6' of the cap or cover, as shewn in Figure 7,
the tightening being effected by bolts applied to the external flanges of
such elbow pipes, or by employing the arrangement shewn in Figures 4,
5, and 6, which arrangement I prefer. This arrangement admits of the
external flanges of the elbow pipes being dispensed with, the pipes being
brought together in their rough,state as cast..
.
The joint is effected in the following manner :- -The two ends of the
elbow pipes to be connected together are surrounded with a sheet of
lead p, "the extremities of which are levelled and lapped one over the
other as shewn in Figure 5%; the whole is then covered with an iron
hoop of rather less width than a sheet of lead, the extremities of
such hoop being bent back and rivetted so as to form an enclosure c, into
which a key d is introduced and driven so as to tighten the leaden
covering with which the pipes are surrounded. The hoop and key are
struck alternately in order to ensure the perfect contact and thorough
tightening of the parts, after which the lead which extends beyond the
edges of the hoop is removed, or pressed, or hammered down. Figure 4"
shows the joint before the lead is thus operated upon, and Figure 4 shews
the finished joint. By this means a perfectly tight joint is obtained,
which is exceedingly strong, may be readily maintained and repaired,
and offers a greater degree of flexibility than any other joint without
danger of rupture.
"
1
These joints, which are applicable to the connecting of tubes in
general, may be also formed with iron hoops made in two or three parts
and tightened by two or three keys according to the diameters. The
joints may also be formed by the aid of pieces of cut tubes forming
simple hoops, the lead being run in between the hoops and the tubes to
be connected, and then finished off as herein-before described.
.Between each two vertical rows of chambers 6 there is an opening or
groove, which grooves are closed by strips t of sheet metal, which are
retained by hand catches, so that the whole of these strips are moveable,
and may be readily removed for the purpose of cleaning the exterior of
the tubes a. By uncovering likewise the opening.o of the chambers b
the inside of the tubes may be cleaned, so that cleaning and repairs may
be effected with the greatest facility, these operations being free from the
difficulties attendant upon boilers of the ordinary construction.
167

page_text: space.
'i
4T
Second. This surface being directly exposed to the fire and most
advantageously situated an enormous evaporation is rapidly produced,
whence a. considerable saving in the consumption of fuel is effected.
+. T.: L'
:
"
Third. The gases in combustion being in a state of division their heat
becomes rapidly and completely absorbed, in the shortest possible
distance.
Fourth. As the caps or covers 6 and the tubes E form'a direct com-
munication between the whole of the tubes a and the reservoirs A and B
the liquid contained in the generator is well circulated, which is
.
F
is one of
the most favorable conditions for rapid and economical evaporation under
the highest pressures in proportion to the diameter of the tubes without
risk of explosion. When the water is greatly charged with calcareous
substances, in which case the substances naturally become deposited in
the feed water reservoir A, the reservoir is proportionally increased in
-size.
18.8
..
"
* f
Fifth. Each tube a is, perfectly, free and independent in the motions of
expansion and contraction to which it is exposed by the changes in the
temperature, such motions being converted into an imperceptible sliding
motion on the washers which form the joint of the covers or caps. The
arrangements' of these cups or covers' admits of any particular tube, or a
whole row of tubes, which may be injured or covered with deposit being
withdrawn without serious loss of time.
13"
Sixth. These generators are exceedingly light as compared to their
power, and-of-unlimited duration, since they are composed of but few
elements, all similar, and which may be always kept-in-hand. They may
be put together and started very rapidly, all of which are considerable a
sources of economy..
14
-
Seventh These generators, which are composed of tubes of from seven-
inchies to seven three-quarter inches in diameter, occupy a very small
space, although they offer a proportionally large amount of heating
surface, and produce in consequence great power. They are very light, a
and consequently may be applied with many advantages not only for thic

page_text: purpose of navigation but also to traction and portable engines, loco-
motives, steam carriages, and other like purposes.
Eighth. The separation of the current of flames to an infinite degree
renders a direct draught more suitable and economical.
Ninth. This generator is superior to all those hitherto employed for
superheating steam, such superheating being proportional to the height
of the level of water.
Tenth. A reheater may be disposed at the upper part of the boiler in
order to absorb and utilize the whole of the heat which escapes from the
latter for the purpose of reheating the feed water.
Eleventh. This apparatus from its arrangement is essentially a smoke
consumer; it may also be applied as a surface condenser, refrigerator, or
to other like purposes.
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used or
carried into effect, I would observe in conclusion that what I consider to
be novel and original, and therefore claim as the Invention secured to me
by the herein-before in part recited Letters Patent is, the herein described
peculiar arrangements and combinations of the tubes and of their con-
nections, which constitute when combined together a tubular steam
generator of improved construction, giving results superior to those
hitherto obtained from apparatus of a similar character.
In witness whereof, I, the said John Henry Johnson, have to this
my Specification set my hand and seal, the Seventeenth day of
June One thousand eight hundred and seventy-two.