IMPROVEMENTS IN TUBULAR STEAM BOLLERS
Year: 1868

page_text: LETTERS PATENT to Loftus Perkins, of Seaford Street, Gray's Inn
Road, Engineer, for the Invention of "IMPROVEMENTS IN TUBULAR
STEAM BOLLERS."
Sealed the 17th October 1868, and dated the 27th April 1868.
PROVISIONAL SPECIFICATION left by the said Loftus Perkins at the
Office of the Commissioners of Patents, with his Petition, on the
27th April 1868.
I, LOFTUS PERKINS, of Seaford Street, Gray's Inn Road, Engineer;
do hereby declare the nature of the said Invention for "IMPROVEMENTS.
IN TUBULAR STEAM BOILERS," to be as follows:-
This Invention relates to the fixing or holding the ends of the tubes
of a tubular steam boiler. For this purpose I cut a. screw thread on the
two ends of each tube, and screw the ends into. holes in the tube plates
which carry them; or if the boiler be constructed in the manner
described in the Specification of a Patent granted to me and another
on the 29th day of September 1859 (No.. 2208) then I screw the ends.

page_text: of the tubes into holes bored in the sides of other larger tubes as
therein described;. afterwards to make tight joints I hammer or close
in around the ends of the tubes the metal which surrounds the holes
into which they have been screwed by this means perfectly tight joints
are obtained. To facilitate the insertion of the tubes into their places
the screw thread at one end of each tube may be longer than the screw
thread at the opposite end; or if the tubes are to be held between two
tube plates a collar may in some cases be welded or fixed on to one
end of each tube, upon which collar the screw thread will then be cut;
the hole in the one tube plate into which this collar screws will there-
fore be larger than the hole in the other tube plate into which the
opposite end of the tube screws. The pipe can thus readily be inserted
into its place through the larger hole, and then screwed at once into
both tube plates.
SPECIFICATION in pursuance of, the conditions of the Letters Patent,
filed by the said Loftus Perkins in the Great Seal Patent Office on
the 27th October 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, LOFTUS
PERKINS, of Seaford Street, Gray's Inn Road, Engineer, 'send
grecting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-seventh day of April; in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-first
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Loftus Perkins, Her special licence that I, the said
Loftus Perkins, my executors, administrators, and assigns, or such otliers
as I, the said Loftus Perkins, my executors, administrators, and 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 King-
dom of Great Britain and Ireland, the Channel Islands, and Isle of
Man, an Invention for "IMPROVEMENTS IN TUBULAR STEAM BOILERS," upon
the condition (amongst others) that I, the said Loftus Perkins, my
executors or administrators, by an instrument in writing 'under my, or

page_text: their, or one of their hands and seals, 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 Loftus Perkins, 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 thereof; that is to say :-
This Invention relates to the fixing or holding the ends of the tubes
of a tubular steam boiler. For this purpose I cut a screw thread on the
two ends of each tube and screw the ends into holes in the tube plates
which carry them, or if the boiler be constructed in the manner
described in the Specification of a Patent granted to me and another on.
the 29th day of September 1859 (No. 2208), then I screw the ends of the
tubes into holes bored in the sides of other larger tubes as therein
described; afterwards to make tight joints I hammer or close in around
the ends of the tubes the metal which surrounds the holes into which
they have been screwed; by this means perfectly tight joints are
obtained. To facilitate the insertion of the tubes into their places the
screw thread at one end of each tube may be longer than the screw
thread at the opposite end, or if the tubes are to be held between two
tube plates a collar may in some cases be welded or fixed on to one end
of each.tube, upon which collar the screw thread will then be cut, the hole
in the one tube plate into which this collar screws will therefore be
larger than the hole in the other tube plate into which the opposite
end of the tube screws; the pipe can thus readily be inserted into
its place through the larger hole and then screwed at once into both
tube plates.
.
And in order that my said Invention may be most fully understood
and moodile comind into effect I will proceed to describe the Drawings

page_text: 'section; Figure 3 is a longitudinal section of the ends of the tube with
portions of the tube plates; Figures 4 and 5 are end views of the tube.
The tubes have each a ring or ferrule welded on at one end, and on this
a screw thread is cut and another screw thread is cut on the other or
smaller end of the tube. The two tube plates are bored with corre-
sponding holes which are tapped to receive the screwed ends of the
pipes; the pipes are inserted through the larger hole and screwed up,
and the joints are then made secure by caulking them on the outer side
with a chisel or caulking tool and a hammer, by which means the metal
of the tube plates around the holes is bulged inwards upon the tubes,
the threaded portions of which are simultaneously indented or burred,
and so perfectly tight and secure joints are obtained; or in place of
making one end of each tube larger than the other by means of a
ferrule they may in some cases where one of the tube plates is moveable
-be left of the same size at each end; they are then screwed a distance
-through. one of.the. plates, and are afterwards turned back to make them
-enter the other plate.; the joints are then caulked as before. Figure 6 is
a side.view, and Figure.7.is.a vertical section of a boiler similar in its
general arrangement to that described in the Specification of the said
.Patent granted to me and another, dated the 29th day of September 1859
. (No. 2208); it consists of a number of horizontal tubes of wrought
.iron c, c, connected together with upright coupling tubes d, d, by which
.the steam generated rises from tube to tube. The lowest row of tubes
-serve as the fire-bars, and over them a cavity is left free for the fire,
the heat from which is caused to circulate to and fro horizontally
between the tubes. The tubes are connected together transversely at
the front and back of the boiler so as to equalize the pressure through-
.out, and the steam.is drawn off at the top.
My present Invention however relates simply to the method of con-
'necting the tubes cand d; this I do in the manner shown on a larger
scale at Figures 8 and 9. Figure 8 is a side view of portions of two of
the tubes c. together with one of the tubes d; Figure 9 is a vertical
section taken at the line 1, 1, Figure 8. The coupling tube d has screw
threads cut on its ends, and corresponding holes are bored and tapped in
the tubes c, c; the tube d is then screwed into one of them so as to enter
it for some distance, and then the other end of the tube d is presented
to its hole in the tube c and made to enter it by turning the tube d
back, so as partly to unscrew it from the first tube. The joints are then
caulked as in the former cases.

page_text: Having thus described the nature of my said Invention, and the
manner of performing the same, I would have it understood that what
I claim is,-
First. The fixing the tubes of tubular boilers into the holes which
receive them by screwing them into their places and caulking the screw
joints as described.
I also claim the use of tubes with enlarged ends with screw threads
upon them, the screwing them into the tube plates, and the caulking
around the screw joints, as described.
In witness whereof, I, the said Loftus Perkins, have hereunto set
my hand and seal, this Twenty-seventh day of October, in the
year of our Lord One thousand eight hundred and sixty-eight.
LOFTUS PERKINS (1.8)