IMPROVEMENTS IN STRAM BOILERS
Year: 1875

page_text: LETTERS PATENT to Killingworth William Hedges, Civil Engineer, of
52, Cheapside, in the City of London, for the Invention of
"IMPROVEMENTS IN STRAM BOILERS."
Sealed the 25th June 1875, and dated the 27th April 1875.
PROVISIONAL SPECIFICATION left by the said Killingworth William
Hedges at the Office of the Commissioners of Patents, with his
Petition, on the 27th April 1875.
I, KILLINGWORTH WILLIAM HEDGES, Civil Engineer, of 52, Cheapside,
in the City of London, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN STEAM BOILERS," to be as follows:-
The Invention relates, firstly, to that class of vertical steam boiler in
which the furnace is placed in the fire-box, and an annular smoke space
is left between the furnace and sides of fire-box to permit of the
smoke and products of combustion after acting on the crown of the
fire-box to pass downwards in such annular smoke space, as heretoforc.

page_text: According to the first part of my Invention, instead of allowing the
products of combustion after descending the annular smoke space to
pass upwards outside the boiler I cause the same to pass through tubes
extending the whole height of the boiler, terminating at top in the
smoke box.
To facilitate the cleaning of these tubes without removing the chimney
I form the outer ring of the smoke box cover in segments, the smoke
pipe being supported by feet resting on top of boiler. The space left
inside tubes on top of boiler can be utilised to place a feed water heater
or superheater, if required.
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To afford access to the furnace, which is made of fire-clay or other
non-combustible materials, such as asbestos or plumbago, besides making
sides and cover of opening communicating with ash-pit removable, I
leave an opening immediately under furnace in base plate of boiler.
This opening is covered with a moveable plate, access being had to it by 1
means of a suitable opening in brickwork foundation of boiler.
For cases where boiler is too small to admit of access to the furnace to
obviate lifting boiler I provide a means of removing furnace. I arrange
the furnace so that it rests on a moveable plate, which can be lowered by
suitable screws. It is kept in position by means of partition between 2
ash-pit and boiler flue. When lowered sufficiently it can be withdrawn
either through bottom of ash-pit or through a suitable opening in bed
plate of boiler.
The second part of my Invention relates to improvements in the
construction of the furnaces to prevent the cracking caused by sudden 2
changes of temperature. Besides forming the furnaces of blocks of fire-
brick, having lugs or projections formed on them as heretofore, I arrange
the joints so that one brick shall partly fit into the other either in a
round or rectangular joint. I also form the connecting piece of fire-door
of a round tube of fire-brick, fixing it to the furnace. In small furnaces a
where they are made entire of fire-clay or plumbago, I form them in
either two or four parts; cach part being fastened together by means of
pins; lateral movement is provided against by forming suitable lugs on
the exterior.
If found desirable to generate steam by gas instead of coal I form the

page_text: furnace in such a manner that pipes pierced with holes can be fixed at
bottom, the furnace itself being filled with asbestos or some other non-
combustible material.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Killingworth William Hedges in the Great Seal
Patent Office on the 25th September 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, KILLING-
WORTH WILLIAM HEDGES, of 52, Cheapside, in the City of London, Civil
Engineer, send greeting.
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 seventy-five, in the
thirty-ninth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Killingworth William Hedges,
Her special licence that I, the said Killingworth William Hedges, my
executors, administrators, and assigns, or such others as I, the said
Killingworth William Hedges, or my exccutors, 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 STEAM BOILERS," upon the
condition (amongst others) that I, the said Killingworth William
Hedges, 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 Killingworth William Hedges, 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 Sheet of-

page_text: I also claim these furnaces if adapted to any other form of fire-box
that may be used in any other kind of boiler to which it may be found
desirable to apply my furnaces.
In witness whereof, I, the said Killingworth William Hedges, have
hereunto set my hand and seal, the Twenty-third day of
September, in the year of our Lord One thousand eight hundred
and soventy-five.