Year: 1886

page_text: Date of Application, 15th May, 1886
Complete Left, 10th Feb., 1887.
Complete Accepted, 22nd Mar., 1887.
I, THOMAS FLETCHER of Thynne Street Warrington in the County of Lancaster
Gas Engineer do hereby declare the nature of this invention to be as follows
This Invention relates to steam boilers and other vessels in which water is or may
be heated and has for its object to increase the effective heating capacity of such
boilers or vessels.
These Improvements consist in constructing or manufacturing the plates or some of the
plates employed in the construction of boilers or water heaters and which are to be
exposed to the source of heat or to the heated gases or products of combustion with
solid projections or protuberances upon one side or surface and they further consist in
constructing or manufacturing the boiler or other vessel with plates having solid
projections or protuberances upon one side or surface thereof these plates being used
only in such positions as may be exposed to the source of heat or to the heated gases
or products of combustion and in such a manner that their projections or protuberances
will be on the side or surface exposed to the heat.
The projections or protuberances are of such a section and of such dimensions that
they may be produced upon the surface of the plate by grooved or otherwise suitably
formed rolls or by other means during the ordinary or any usual or convenient process
of manufacture.
WILLIAM E. HEYS,
70, Market Street, Manchester,
Agent for the Applicant.

page_text: Improvements in or relating to Steam Boilers and other Vessels in
which Water is Heated.
I, THOMAS FLETCHER, of Thynne Street, Warrington, in the County of Lancaster,
Gas Engineer, do hereby declare the nature of this invention, and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
This Invention relates to steam boilers and other vessels in which water is or may be
heated and has for its object to increase the effective heating capacity of such boilers
and vessels.
It is known that when a metallic surface upon one side of which there is water has
its other side exposed to a flame or to highly heated gases, there is a zone or space
between the flame or gases and the metallic surface which offers great resistance to the
transfer of heat from the flame or gases to the metal and consequently to the water
upon the metal. This has been demonstrated by cementing paper upon the bottom of
a kettle or the flue of a boiler containing water, and then allowing flame or heated
gases to play upon it, when, so long as the paper is in actual contact with the metal
and water remains on the opposite side the paper continues uninjured. Further, upon
looking at the bottom of the kettle or the surface of the flue the dark or cold zone
becomes visible. I have for a long time past sought to extinguish diminish or
overcome the resistance to the transfer of heat through the cold zone, which I found
could be effected to a considerable extent, experimentally, but in an impracticable form,
by fully exposing metal rods to the action of the flame or hot gases, and bringing them
into contact with the heating surface while so exposed. Similar rods attached to the
heating surface quickly burnt away at their free ends until they were reduced to definite
dimensions dependent on the conditions of use; and their employment, when first
constructed of the correct dimensions, although in many cases unsuitable, and sometimes
involving a dangerous risk was found to be comparatively satisfactory in other instances;
their efficiency moreover was found to be far less than the hereinafter described methods
of construction, which constitute my present Invention.
These Improvements consist in constructing or manufacturing the metal plates or
some of the plates employed in the construction of boilers and water heaters and which
are to be exposed to the source of heat or to the heated gases or products of combustion
in or upon the boiler or water heater, with solid projections or protuberances upon one
side or surface. These Improvements further consist in constructing or manufacturing
the boiler or other water heating vessel with or from metallic plates having solid
projections or protuberances upon one side or surface thereof, these plates being used
by preference in such positions only as may be exposed to the action of flame or heated
gases or products of combustion and in such a manner that the projections or pro-
tuberances are upon the side or surface of the plates exposed to the action of the flame
or heated gases.

page_text: The exact dimensions of the projections or protuberances formed upon the plates
will depend, among other conditions, upon the thickness of the plate and the tempera-
ture of the flame or gases, but for ordinary purposes a total projection from the normal
surface of the plate of about three quarters of an inch will be found convenient, while
with a mean thickness of three sixteenths of an inch they may be advantageously
placed about half an inch apart.
The form of the projections or protuberances is not material provided that they are
such as can be produced by rolling, casting, pressure, forging, or by other ordinary or
equivalent means, during or subsequent to the process of manufacture of the plate;
and so that they form integral parts thereof.
I desire it to be understood that I do not make any general claim to the use of
projections such as tubes rods and the like attached to or inserted in the heating surfaces
of boiler plates as these have been publicly known and used for some years, as for
example in Field" Boilers, the rivet heads of fire boxes, and screwed studs in
marine boilers.
Having now particularly described and ascertained the nature of my said Invention
and in what manner the same is to be performed, I desire it to be understood that
what I claim is :-
(1) The manufacture or construction of metallic plates to be employed in the con-
struction of boilers and other vessels in which water is to be heated, said manufacture
or construction consisting in forming or producing projections or protuberances on
the heating surface of such plates, substantially as and for the purpose hereinbefore
described.
(2) Plates to be employed in the construction of the heating surfaces of boilers and
water heaters, and having integrally formed or produced upon one surface thereof
solid projections or protuberances; substantially as and for the purpose hereinbefore
described.
(3) In the construction of the heating surfaces of boilers and other vessels in which
water is to be heated, the use of plates having solid projections or protuberances
integrally formed thereon, said projections or protuberances being so disposed or
arranged as to be exposed to the action of the flame or heated gases; substantially as
and for the purpose hereinbefore set forth and described.
Dated this 9th day of February & D 1907
WILLIAM E. HEYS,
70, Market Street, Manchester,
Agent for the Applicant.