IMPROVEMENTS IN STEAM BOILERS
Year: 1870

page_text: LETTERS PATENT to John Hosking, Engineer, and John Morrison,
Mechanic, both of Gateshead Iron Works, Gateshead, in the
County of Durham, for the Invention of "IMPROVEMENTS IN STEAM
BOILERS,"
Sealed the 6th June 1871, and dated the 12th December 1870.
PROVISIONAL SPECIFICATION left by the said John Hosking and
John Morrison at the Office of the Commissioners of Patents, with
their Petition, on the 12th December 1870.
We, JOHN HOSKING, Engineer, and JOHN MORRISON, Mechanic, both
of Gateshead Iron Works, Gateshead, in the County of Durham, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
STEAM BOILERS," to be as follows:-
-
Our Invention has for its object the application and use of corrugated
instead of flat rolled plates in the construction of steam boilers
generally, but more especially in the construction of the cylindrical
tubes and flues for the same, whereby a greater strength to resist pressure
is obtained.

page_text: cases are used as means of strengthening the tubes or flues may be
dispensed with.
The pitch and depth of the corrugations may be varied as required.
and will always be in the direction of the hoop or curved form of the
tubes or flues.
This mode of construction has also the advantage of giving more
heating surface, and likewise admits of a greater freedom for expansion
and contraction than when made of flat rolled plates. The deteriorating
effects often produced by these causes will be abated by such freedom.
The corrugations contemplated for the plates are similar to those
commonly used for roofing purposes and for bridge roadway flooring,
where strength and stiffness are required. They may however be varied
in their form as required.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Hosking and John Morrison in the Great
Seal Patent Office on the 10th June 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN
HOSKING, Engineer, and JOHN MORRISON, Mechanic, both of Gateshead
Iron Works, Gateshead, in the County of Durham, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of December, in the year
of our Lord One thousand eight hundred and seventy, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said John Hosking and John Morrison,
Her special licence that we, the said John Hosking and John Morrison,
our executors, administrators, and assigns, or such others as we, the said
John Hosking and John Morrison, 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 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 John Hosking and John
Morrison, 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

page_text: 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 John Hosking and John Mor-
rison, do hereby declare the nature of our 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 Drawings hereunto annexed, and to the letters and figures marked
thereon (that is to say) :-
Our Invention of "Improvements in Steam Boilers" has for its object
the application and use of corrugated instead of flat rolled plates in the
construction of steam boilers generally, but more especially in the con-
struction of the cylindrical tubes and flues for the same, whereby a
greater strength to resist pressure is obtained.
By this mode of construction thinner plates may be used for a given
strength of resistance to pressure, and the rings or hoops which in many
cases are used as means of strengthening the tubes or flues may be
dispensed with.
The pitch and depth of the corrugations may be varied as required
and will always be in the direction of the hoop or curved form of the
tubes or flues.
This mode of construction has also the advantage of giving more
heating surface and likewise admits of a greater freedom for ex-
pansion and contraction in the tubes than when made of flat rolled
plates. The deteriorating effects often produced by these causes will be
abated by such freedom.
The corrugations contemplated for the plates are similar to those
commonly used for roofing purposes and for bridge roadway flooring
when strength and stiffness are required. They may however be varied
in their form to suit different constructions and dimensions of tubes and
flues and other parts of boilers.
The jointing of the corrugated plates so as to make them into the
required form of tube, flue, or other part of boiler may be effected by
rivetting or by other approved mode of jointing.
In order however that our said Invention may be fully understood
and readily carried into effect, we will proceed to describe it more
particularly by the aid of the accompanying Drawings, in which are
represented different modes of applying our Invention.

page_text: DESCRIPTION OF THE DRAWINGS.
Fig. 1 is a longitudinal section of an ordinary cylindrical boiler with
the internal tube only made of corrugated plates; Fig. 2 is an end view
of the same; Fig. 3 is a longitudinal section of a similar boiler with the
longitudinal plates of both the case and tube made of corrugated plates;
Fig. 4 is an end view of the same.
Fig. 5 is a longitudinal section shewing another class of boiler in which
corrugated plates may be used either wholly or in part; Fig. 6 is an end
'view of the same.
In Figures 3, 4, 5, and 6 the longitudinal strips marked a, a, may be of
any suitable section, such as a flat bar, or of "tee" or "angle" shaped
form, and are intended to prevent any undue stretching or expansion of
the outer shell or casing of the boiler in a longitudinal direction.
Having thus described the nature of the said Invention, and in what
manner the same is to be performed, we hereby declare that we do
not claim as of our Invention the use of corrugated plates otherwise
than as herein-before described and herein-after stated; but what we
do claim as of our Invention is, the use of corrugated iron, copper,
or other plates in the construction of the cylindrical tubes or flues
and other parts of steam boilers, whereby a greater strength to resist
pressure is obtained.
In witness whereof, we, the said John Hosking and John Morrison,
have hereunto set our hands and seals, the Eighth day of June,
in the year of our Lord One thousand eight hundred and seventy-
ona
Witness,
WILLIAM DALRYMPLE,
35, Alexandra Road,
Gateshead-on-Tyne,
Engineer.
(L.S.)
JOHN HOSKING.
JOHN MORRISON. (L.S.)