IMPROVE- MENTS IN THE CONSTRUCTION OF STEAM GENERATORS
Year: 1862

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, and of 166, Buchanan Street, in the City
of Glasgow, North Britain, Gentleman, for the Invention of "IMPROVE-
MENTS IN THE CONSTRUCTION OF STEAM GENERATORS."-A communication
from abroad by Joseph François Bérendorf, of Paris, in the Empire of
France, Engineer.
Sealed the 12th May 1863, and dated the 8th December 1862.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on the
8th December 1862.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of 166, Buchanan Street, in the City of Glasgow, North
Britain, Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE CONSTRUCTION OF STEAM GENERATORS," a communication
from abroad by Joseph François Bérendorf, of Paris, in the Empire of France,
Engineer, to be as follows:-
This Invention relates more particularly to multitubular boilers or steam
generators, and comprises an improved manufacture, arrangement, and mode
of fitting or adjusting the tubes in the tube plates, whereby greater facility is
afforded for introducing, removing, and cleaning the same. The tubes when

page_text: secured in their places according to this Invention are not contracted or
obstructed by the presence of any internal rings or ferrules, so that the
cleaning of the same is more easy of execution, and the draught is unimpeded.
According to one mode of carrying out this Invention, as applied to a
system of tubular boiler with return tubes, it is proposed to adapt a fan or
other exhauster to the rear end of the set of tubes, which act as the return
tubes, whereby the draught can be increased or diminished at pleasure, and
the heated gases and products of combustion are directed or forced by opening
or closing certain valves, either direct into the chimney, or along other flues or
passages leading into the ash-pit, or along special flues, for the purpose of
heating ovens, or drying stoves, or for warming the workshop. When pro-
vided with return tubes it is preferred to construct the barrel of the boiler of
two horizontal, cylindrical, or partially cylindrical shells, which are rivetted at
one end to the main upright cylindrical portion of the boiler containing the
fire-box, and surrounded by a steam dome. Two series or sets of tubes are
introduced, one, set in each of the horizontal shells. The lower set of tubes
are fitted at one end into the fire-box, and at the other end into a tube. plate
forming part of the smoke-box or combustion chamber. The upper or return
set of tubes are connected with the smoke-box at one end, and with a cast-
iron chamber opening on one side under the mouth or entrance to the
chimney, which is situate at the front or fire-box end of the boiler. Immedi-
ately in front of this cast-iron chamber there is fitted a fan or exhauster
contained in a suitable case, which greatly assists the draught, and com-
municates at its upper portion direct to the chimney, which is provided with a
valve or damper, and at the sides with two lateral descending flues or passages,
which open under the grate bars in the closed ash-pit, or into special flues or
passages for heating or drying purposes; valves or dampers are also provided
in these descending flues, so that the products of combustion may either be
directed at once into the chimney, or shut off from the chimney, and directed
into the ash-pit, or along the spiral flues. The adjustment or fitting in of the
tubes is effected after the boiler is completed, and the holes have been made
in the respective tube plates. Into these holes are inserted two slightly
tapered cutters, having their cutting surfaces extending only about half round.
These cutters, one for each plate, are both fitted on to a long rod, which is
passed from one hole to the opposite one, so that each cutter will operate
simultaneously upon the two corresponding holes in the two tube plates, the
first cutter being made rather smaller than the other, in order to allow of its
passing through the hole in the first tube plate. By rotating the rod the
cutters impart a slightly conical form to the holes. To each extremity of the

page_text: tube to be inserted is fitted externally a slightly conical or tapered ferrule;
the first or entering ferrule being rather smaller than the second, so as to pass
through the first tube plate. Into this tube is inserted longitudinally a rod
screwed at both ends, and carrying at each extremity a washer, and a nut
outside thereof. One of these washers bears only upon the end of the tube
itself, whilst the other, which is made hollow, and of larger diameter, bears
at its edges only upon the tube plate immediately round the end of the tube:
By tightening up the nut at the back of the last-named washer, the tube will
be forcibly drawn into the conical holes in the tube plates, and firmly secured
therein. When the tubes are to be removed the positions of the washers are
reversed, and by again tightening the nuts the tubes will be drawn out of
their holes in the tube plates. A few strokes of the hammer upon the smaller
washer will greatly assist the insertion and removal of the tubes.
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 8th June 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex, and
of 166, Buchanan Street, in the City of Glasgow, North Britain, Gentleman,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighth day of December, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Henry' Johnson, Her special license that I, the said John
Henry Johnson, my executors, administrators, and assigns, or such others as
I, the said John Henry Johnson, my executors, administratörs, 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 THE CONSTRUCTION OP STEAM GENERATORS," a communication
from abroad by Joseph François Berendorf, of Paris, in the Empire of France,
Engineer, 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, or under the hand and seal of one of them, should par-

page_text: ticularly 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 accompanying Drawings, and
to the letters and figures marked thereon, that is to say :-
The said Invention relates more particularly to multitubular boilers or
steam generators, and comprises also an improved construction and mode or
method of fitting or adjusting the tubes in the tube plates, whereby greater
facility is afforded for introducing, removing, and cleaning the same. The
tubes when secured in their places according to this Invention are not con-
tracted or obstructed by the presence of any internal rings or ferrules, so that
the cleaning of the same is more easy of execution, and the draught is
unimpeded.
According to the first part of this Invention, it is proposed to adapt a fan or
other exhauster to the rear end of the set of tubes which act as the return
tubes in multitubular boilers, whereby the draught can be increased or
diminished at pleasure, and the heated gases and products of combustion are
directed or forced by opening or closing certain valves, either direct into the
chimney, or along other flues or passages leading into the ash-pit, or along
special flues, for the purpose of heating ovens or drying stoves, or for warming
the workshop. The barrel of the boiler is rivetted at one end to the main
upright cylindrical portion of the boiler containing the fire-box, and sur-
mounted by a steam dome. Two series or sets of tubes are introduced into
the shell, one set above the other horizontally; the lower set of tubes are
fitted at one end into the fire-box, and at the other end into a tube plate
forming part of the smoke-box or combustion chamber. The upper or return
set of tubes are connected with the smoke-box or combustion chamber at one
end, and with a chamber opening on one side under the mouth or entrance
to the chimney, which is situate at the front or fire-box end of the boiler.
Immediately in front of this chamber there is fitted a fan or exhauster, con-
tained in a suitable case, which greatly assists the draught, and communicates
at its upper portion direct with the chimney, which is provided with a valve
or damper, and at the sides with two lateral descending flues or passages,
which open under the grate bars in the closed ash-pit, or into special flues or
passages for heating or drying purposes. Valves or dampers are also provided

page_text: in these descending flues, so that the products of combustion may either be
directed at once into the chimney, or shut off from the chimney, and directed
into the ash-pit, or along the special flues. The adjustment or fitting in of
the tubes is effected after the boiler is completed, and the holes have been
made in the respective tube plates. Into these holes are inserted two slightly
tapered cutters, having their cutting surfaces extending only about half way
round; these cutters, one for each plate, are both fitted on to a long rod,
which is passed from one hole to the opposite one, so that each cutter will
operate simultaneously upon the two corresponding holes in the two tube
plates, the first cutter being made rather smaller than the other in order to
allow of its passing through the hole in the first tube plate. By rotating the
rod the cutters impart a slightly conical form to the holes. To each extremity
of the tube to be inserted is fitted externally a slightly conical or tapered
ferrule, the first, or entering ferrule, being-rather smaller than the second, so
as to pass through the first tube plate. Into this tube is inserted longitudinally
a rod screwed at both ends, and carrying at each extremity a washer, and a
nut outside thereof. One of these washers bears only upon the end of the
tube itself, whilst the other, which is made hollow, and of larger diameter,
bears at its edges only upon the tube plate immediately round the end of the
tube. By tightening up the nut at the back of the last-named washer, the
tube will be forcibly drawn into the conical holes in the tube plates, and
firmly secured therein. When the tubes are to be removed the positions of
the washers are reversed, and by again tightening the nuts the tubes will be
drawn out of their holes in the tube plates. A few strokes of the hammer
upon the smaller washer will greatly assist the insertion and removal of
the tubes.
And in order that the said Invention may be fully understood, I shall
now proceed more particularly to describe the same, and for that purpose
I shall refer to the several Figures on the Sheet of Drawings hereunto
annexed, the same letters of reference indicating corresponding parts through-
out all the corresponding Figures.
Figure 1 of the Drawings represents a longitudinal vertical section of a
tubular boiler adapted for marine engines; Figure 2 is a front elevation of
the same; and Figure 3 is a transverse vertical section, taken along the line
1, 2, in Figure 1.
This generator, which is contained within the outer shell G upon which the
steam dome K is fitted, is provided with two separate furnaces F, F', the
tubes T of which open into the same smoke-box or combustion chamber E, in
the upper part of which are fitted the series of return tubes T'. These tubes

page_text: open into a second chamber or smoke-box D surmounted by the chimney C.
To avoid all loss or waste of heat, the smoke-box E is closed by a door B
lined with fire-brick. The second smoke-box D is provided with a metal
door d, to facilitate the cleaning and removal of the tubes. The furnaces F
and F¹, as well as the tube plate A of the first box E are moveable, in order to
facilitate the cleaning of the interior of the body of the other boiler G, for which
purpose they are, merely bolted to the ends of the boiler. Each of the furnaces
is rivetted to a frame f, which is fixed to the body of the boiler by a number
of bolts ; the tube plate A is similarly provided with a frame f¹, strongly
held in place by the bolts a (Figure 1). When it is required to remove the
tubes it is simply necessary to unscrew the bolts which hold the frames f
and f¹, whereupon the fire-box and the tube plate A may be readily removed.
The fitting of the tubes is effected after the boiler is completed and put
together, the tube plates being perforated with slightly conical holes before
the tubes are inserted into them. Figure 4 represents in longitudinal section
one of the tubes detached, with the middle part broken away, and having its
extremities slightly tapered, but one end is of larger external diameter than
the other, to allow of the passage of the smaller end through the hole in the
first tube plate. Figure 5 represents the end of a tube provided with an
external ferrule of a slightly conical or tapered form. In adopting these
tubes to existing boilers, the holes for receiving the tubes are prepared by a
"rimer," or tool provided with two tapered or conical file cutters, as shewn at
Figure 6, which Figure also indicates the rod and washers employed in fitting
in and removing the tubes. The cutters f and f' are serrated or roughened
on one half of their circumference only. The cutter f¹ is, of course, of
larger diameter than the cutter f, in order to admit of the entrance of the
tube. The insertion of the tube is effected by the rod L, which is screwed at
each extremity, and carries at each screwed portion a washer M and M¹ of
different forms, as well as the nuts m and m¹. The washer M bears against
the end of the tube, whilst the other, M', bears against the surface of the
tube plate. In fitting in the tubes the washer M' must be placed on the plate
through which the end of the tube is to be forced, as in Figure 6, when if
the nut m on the rod L be tightened up, that rod will be drawn in the
direction of the arrow, and the washer M being pressing against the opposite
end of the tube will force it into its place. It is advisable to commence with
the tubes on the outer edge, in order to have a better and firmer support on
approaching the centre of the tube plates. The removing of the tubes is
effected by simply reversing the relative positions of the washers M, M¹, as
shown in Figure 6b, when the tightening of the nut m¹ will draw the rod L in

page_text: the direction shewn by the arrow, and the washer M bearing against the
smaller end of the tube will force it out of its tube plates. A few blows of a
hammer upon the washer M will in all cases facilitate and expedite the proper
insertion and removal of the tubes. The one of external conical ferrules,
shewn in Figure 5, will be found preferrable in all cases where the water has a
particular tendency to form a deposit, as in marine boilers. It is, therefore,
necessary in such cases that the diameter of the ferrules over and above that
of the exterior of the tube should be more than the thickest deposit likely to
be found upon such tube, so that the tube with the deposit upon it will pass
through the hole in the tube plate left by the outer ferrule. Without this
proviso the deposit on the tube would tend to prevent its withdrawal through
the hole in the tube plate.
Figure 7 represents a longitudinal section of a tubular boiler with return
tubes fitted with a fan or ventilator, for increasing the draught, and for
returning the gases if desired under the furnace bars, or along special flues or
conduits for heating purposes. Figure 8 is a transverse section, taken along
the line 3, 4. The boiler is composed of the main outer shell G, in which is
fitted a furnace F, and which is surmounted by a steam dome K. Two sets of
tubes, T and T, are fitted in the barrel, and by the upper set the flame
returns to the chimney. These tubes are mounted or fixed and removed in
the manner herein-before described. The tubes T are fitted at one end into
the fire-box F, and at the opposite end into the smoke-box E, whilst the
tubes T connect this box with a second box D, and in connection with this
second box there is a fan or exhauster H, which can be made to communicate
direct with the chimney at its upper side, or with lateral vertical passages
provided with valves or dampers, and leading into the ash-pit, or into tubes or
flues for heating purposes. On driving the fan the gases and products of
combustion are drawn through the tubes T', and forced by the aid of valves or
dampers, which are opened or shut accordingly, either direct into the chimney,
or into the furnace again, or through heating flues or pipes. When the gases
are employed for assisting combustion in the furnace, the ash-pit should be
closed, having a plate in front provided with a small sliding door for the
passage of air.
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,-
1st, the peculiar combination of tubes and smoke boxes or combustion

page_text: chambers with a fan or exhauster chimney, and conducting flues or passages,
substantially as herein-before described.
2nd, the mode or method of securing and removing the tubes of steam
generators in and from their tube plates, as herein-before described.
3rd, the peculiar combination and arrangement of apparatus for inserting
and removing the tubes in and from the tube plates of steam generators, as
herein-before described.
In witness whereof, I, the said John Henry Johnson, have hereunto set
my hand and seal, this Eighth day of June, in the year of our Lord
One thousand eight hundred and sixty-three.
J. HENRY JOHNSON. (L.S.)