IM- PROVEMENTS IN STEAM BOILERS
Year: 1872

page_text: LETTERS PATENT to George Weir, of Glasgow, in the County of
Lanark, North Britain, Engineer, and James Weir, of Liverpool,
in the County of Lancaster, Engineer, for the Invention of "IM-
PROVEMENTS IN STEAM BOILERS."
Scaled the 23rd July 1872, and dated the 26th January 1872.
PROVISIONAL SPECIFICATION left by the said George Weir and
James Weir at the Office of the Commissioners of. Patents, with
their Petition, on the 26th January 1872..
We, GEORGE WEIR, of Glasgow, in the County of Lanark, North
Britain, Engineer, and JAMES WEIR, of Liverpool, in the County of
Lancaster, Engineer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN STEAM BOILERS," to be as follows, that is to
say:-
-

page_text: tube plates and to any of the flue or furnace plates that are liable to be
too strongly acted upon by the heat; and such protection is more par-
ticularly needed in what are termed "high-pressure" boilers.
The improvements will also render steam boilers less apt to prime.
.
In carrying out the Invention a refractory substance such as fire-clay
is applied to the outside of the tube plates or other plates, either by
plastering it on or by fixing on slabs or shells of it. When applying
the fire-clay by plastering it, plugs are put into the ends of the tubes to
be removed after the fire-clay is set or dried, and to hold it in its place
rough-headed pins are screwed or fixed into the tube plate at numerous
points and become embedded in it. When slabs or shells of fire-clay
are used they are held by pins screwed into the tube plate, and either
such slabs, or shells, or the plastered material may be additionally
supported by bands or strips of sheet iron which can be easily renewed
on burning out.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Weir and James Weir in the Great Seal
Patent Office on the 25th July 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, GEORGE
WEIR, of Glasgow, in the County of Lanark, North Britain, Engineer,
and JAMES WEIR, of Liverpool, in the County of Lancaster, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-sixth day of January, in the
year of our Lord One thousand eight hundred and seventy-two, in the
thirty-fifth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto us, the said George Weir and James
Weir, Her special licence that we, the said George Weir and James
Weir, our executors, administrators, and assigns, or such others as we;
the said George Weir and James Weir, our 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

page_text: United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN STEAM BOILERS,"
upon the condition (amongst others) that we, the said George Weir and
James Weir, our executors or administrators, by an instrument in writing
under our, or 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 we, the said George Weir and James Weir, do
hereby declare the nature of our said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement in writing, reference being
had to the accompanying Drawings, that is to say :—
Our said Invention has for its object to increase the durability of
steam boilers, and consists in applying protective coatings or coverings
to the tube plates and to certain of the flue or furnace plates which are
liable to be too strongly acted upon by the heat; and such protection is
more particularly needed in what are termed "high-pressure "boilers.
Our improvements will also render steam boilers less apt to prime than
heretofore.
And in order that our said Invention and the manner of performing
the same may be properly understood, we hereunto append two Sheets
of explanatory Drawings to be herein-after referred to, and representing
two modes of applying our improvements. In these Drawings the same
reference numerals are used to mark the same or like parts wherever
they are repeated.
Figures 1 and 2. are vertical sections as at right angles to each other
of a marine steam boiler as furnished with our protective coatings. This
boiler has two furnaces 1, which communicate at their inner ends with a
combustion chamber 2, and the upper part of this combustion chamber 2
communicates by horizontal flue tubes 3 with a smoke box 4 and
uptake 5. It is the tube plate 6 in the combustion chamber 2 which in
ordinary boilers is so apt to give trouble from being too strongly acted
on by the heat, and we apply to this tube plate a protective covering 7
of a suitable refractory substance such as fire-clay. This covering or

page_text: coating may be applied by plastering on the substance when in a plastic
condition, and in this case plugs are put into the ends of the tubes 3, to
be removed afterwards when the fire-clay is set or dried, and to hold it in
its place rough headed pins are screwed or otherwise fixed into the tube
plate at numerous points and become embedded in it. We, however,
prefer to form the protective covering of small shells, blocks, or suitably
shaped pieces of fire-clay, which are prepared and burned separately.
Figure 3 is an enlarged face view, showing a few of the blocks 7 as
placed in position, and Figure 4 is a section as at the line A-A, in
Figure 3, whilst Figure 5 is a section as at the line B-B. The blocks
are made of the best quality of fire-clay but of a somewhat porous con-
sistency, and they are shaped so that their different parts may vary as
little as possible in breadth or thickness, in order that they may not be
liable to crack with changes of temperature. The blocks 7 are held by
pins 8, either screwed into the tube plate 6 as at 9, or fixed by hammer-
ing in as at 10, the blocks being formed with tapered holes to pass over
the pins 8. The pin holes in the blocks 7, and also small cavities 11
formed between the joints of the blocks, are filled in with plastic
clay when the blocks are in place. A series of fire-clay blocks 12 are
fixed in a similar manner round the upper part of the fire-bridge
opening 13, for the purpose of protecting the joint between the tube
plate 6 or saddle plate and the furnace plate 14.
Figures 6 and 7, on Sheet 2 of the Drawings, are vertical sections as
at right angles to each other, and showing a pair of boilers combined
together back to back, with one casing and uptake 5. In this example
a fire-brick combustion chamber 15 is formed between the two boilers,.
thus dispensing with the inconvenient water spaces ordinarily con-
structed at the back of the combustion chamber. The tube plates 6, 6,
in this combustion chamber are protected by the coverings 7 of fire-
clay or fire-clay blocks, as in the first modification herein-before
described.
Having thus particularly described our said Invention, and the manner
in which the same is to be performed, we have to state that we do not
restrict ourselves to the precise details herein described or delineated,
but that what we believe to be novel and original, and claim as the
Invention secured to us by the herein-before in part recited Letters
Patent is, the applying of protective coatings or coverings of a refractory

page_text: substance, such as fire-clay, to the tube plates and furnace plate joints
of steam boilers, substantially as and for the purposes herein-before
described.
In witness whereof, I, the said James Weir, on behalf of the
said George Weir and myself, have hereunto set my hand and
seal, this Twenty-fourth day of July, in the year of our Lord
-One thousand eight hundred and seventy-two.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
JAMES WEIR. (L.S.)