IMPROVED APPARATUS FOR PREVENTING THE EXPLOSION OF STEAM GENERATORS
Year: 1874

page_text: LETTERS PATENT to Edward Thomas Hughes, of the Firm of
Hughes and Son, Patent Agents, 123, Chancery Lane, London, for
the Invention of "IMPROVED APPARATUS FOR PREVENTING THE EXPLOSION
OF STEAM GENERATORS."-A communication from abroad by Messieurs;
Dl ea
CL T
Deale
caled the 2nd March 1874, and dated the 3rd September 1874.
PROVISIONAL SPECIFICATION left by the said Edward Thomas Huglies
'
at the Office of the Commissioners of Patents, with his Petition, on.
the 3rd September 1874.
I, EDWARD THOMAS HUGHES, of the Firm of Hughes and Son,
Patent Agents, 123, Chancery Lane, London, do hereby declare the
nature of the said Invention for "IMPROVED APPARATUS FOR PREVENTING
THE EXPLOSION OF STEAM GENerators,' a communication to me from
abroad by Messieurs Barbe & Co., of Molenbeek, St. Jean, Brussels, to
be as follows:-
"
The object of this Invention is to prevent accidents arising from the
liability of steam generators to explosion, and the apparatus consists
of a tubular piece which is cast to the back part of the boiler, and
in the interior of which tube is arranged a conical disc of lead or

page_text: other material according to the dimensions of said disc, such dimensions
varying according to the pressure which the steam attains or does not
exceed.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Thomas Hughes in the Great Seal Patent
Office on the 3rd March 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
THOMAS HUGHES, of the Firm of Hughes and Son, Patent Agents, 123,
Chancery Lane, London, send grecting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Third day of September, in the year
of our Lord One thousand cight hundred and seventy-four, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Edward Thomas Hughes, Her
special licence that I, the said Edward Thomas Hughes, my executors,
administrators, and assigns, or such others as I, the said Edward Thomas
Hughes, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times there-
after 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 Inven-
tion for "IMPROVED APPARATUS FOR PREVENTING THE EXPLOSION OF STEAM
GENERATORS," a communication to me from abroad by Messieurs Barbe
& Co., of Molenbeek, St. Jean, Brussels, upon the condition (amongst
others) that I, the said Edward Thomas Hughes, my executors or
administrators, by an instrument in writing under my, 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 I, the said Edward Thomas Hughes, 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 Figures on the

page_text: accompanying Sheet of Drawings, and to the letters of reference marked
thereon (that is to say) :-*
The object of this Invention is to prevent accidents arising from the
liability of steam generators to explosion..
The apparatus consists of a kind of dome cover or valve box a made
of cast iron or any other suitable material, and provided with a valve b
and a conical seating, the depth or thickness of the valve and seating
being made in proportion to the pressure of the steam or the number of
atmospheric pressures desired to be resisted, but not to exceed that,
there being a screw e in a cross piece or connection f, so adjusted as to
prevent the valve b from going too far towards the interior of the boiler.
A groove d is cut in the edge of the valve, and extending around same,
the groove being filled with tin, lead, or other suitable material to
increase the diameter of the valve to the size of the valve box or seating.
And this apparatus can be applied to all descriptions of boilers, and
should be placed at the lowest possible part of the boiler. By means of
this apparatus the moment the pressure in the boiler attains the number
of atmospheres or the maximum pressure determined upon, and not
exceeding it, the metal in the groove of the valve will give way and the
boiler be emptied of water and steam in a few seconds without any
danger or havoc.
This apparatus is not identical with the ordinary fusible plug, which
only acts when the shell of the boiler where it is placed is nearly
at a red heat; whereas this apparatus is acted upon simply by the
pressure.
Having now described the nature and particulars of the said In-
vention, I claim, the improved apparatus for preventing the explosions of
steam boilers, as described and illustrated.
In witness whereof, I, the said Edward Thomas Hughes, have
hereunto set my hand and seal, this Third day of March, in
the year of our Lord One thousand eight hundred and seventy-
five