Improvements in or connected with Tubular Steam Boilers and their Furnaces.
Year: 1892

page_text: Date of Application, 17th Nov., 1892
Complete Specification Left, 28th Dec., 1892-Accepted, 28th Jan., 1893
PROVISIONAL SPECIFICATION.
Improvements in or connected with Tubular Steam Boilers and
their Furnaces.
I JOHN DEVONSHIRE ELLIS Managing Director of John Brown and Company
Limited Atlas Steel and Iron Works Sheffield in the County of York do hereby
declare the nature of this invention to be as follows:-
My invention consists in a new combination of devices or arrangements connected
with tubular steam boilers and their furnaces whereby the heating effect and
economy and facility of working of such boilers and furnaces are improved.
According to my invention I employ in combination induced draught, the heating
of the air supply by the otherwise waste heat of the furnace or furnaces and tubes
(preferably internally ribbed tubes) having in them spiral plates or equivalent
retarding devices by which the hot gases from the furnace are drawn through the
tubes by induced draught and deflected and caused to come into contact most
efficiently with the very extended heating surfaces in the said tubes. The hot gases
after passing from the boiler tubes are drawn by a fan or other exhausting device
into contact with tubes or passages through which the air to supply the furnace
passes so that the said air which is drawn in by induced draught becomes heated by
the waste gases before passing into the furnace.
Dated this 17th day of November 1892.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, Agents.
COMPLETE SPECIFICATION.
Improvements in or connected with Tubular Steam Boilers and
their Furnaces.
I, JOHN DEVONSHIRE ELLIS, Managing Director of John Brown & Company,
Limited, Atlas Steel and Iron Works, Sheffield, in the County of York, 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 :-
My invention consists in a new combination of devices or arrangements connected
with tubular steam boilers and their furnaces whereby the heating effect and
economy and facility of working of such boilers and furnaces are improved so that
the efficiency of a given boiler when working with natural draught may be greatly
increased and even multiplied several times without loss of economy and without
difficulties in working.
According to iny invention I employ the combination of firstly induced draught,
secondly the heating of the air supply for the furnace or furnaces by the otherwise
waste heat of the said furnace or furnaces and thirdly tubes (preferably internally
ribbed tubes commonly known as serve tubes") having in them spiral plates or
equivalent retarding devices by which the hot gases from the furnace or furnaces
drawn through the tubes by induced draught are deflected and caused to come into
contact most efficiently with the very extended heat absorbing surfaces in the said
tubes. In the said combination the hot gases from the furnace or furnaces are
drawn through the said tubes by a fan or other exhausting device so that after
leaving the boiler they are caused to come into contact with tubes or passages
Pine 871

page_text: through or around which the air to supply the furnace or furnaces passes so that
the said air which is drawn in by induced draught becomes heated by the waste
gases before passing into the furnace or furnaces. In addition cold air in any
amount required may when desired be drawn through openings for instance in the
ash pit door.
The accompanying drawing represents in Figures 1 and 2 in sections at right
angles to each other a marine boiler provided with an arrangement according to
my invention. In this arrangement the hot gases come into contact with the
exterior of the tubes and the incoming air passes into the tubes but the reverse of
this may be employed if desired. A are the furnaces having separate compartments
in front, those marked B for the products of combustion from the tubes E and
those marked C for the air supply to the furnaces. Above the boiler are nests of
tubes D situated in casings into which the products of combustion (which have
passed into the compartments B from the boiler tubes E) pass by openings 'd and
leave by the openings d passing thence into an uptake F from which they pass into
a fan G which causes the passage of the heated gases as aforesaid from the furnaces
then through the tubes E, then through the casings B and by the openings d through
the casings containing the tubes D'and' through the openings d to the uptake F
and thence to the fan G.
.
X..
h
Although I have shown the tubes D as being in a horizontal position and that
position may probably be most efficient I do not limit myself to that position 'as
they may be placed at any angle which circumstances may render desirable and the
said tubes may be arranged in other than the direction longitudinally of the boiler
as shewn if desired.
1
The air for supplying the furnaces by the same fan G is drawn through the
tubes D and thus becomes heated by the hot gases passing around them' and the air
so heated then passes through the compartments C and by openings regulated by
valves into casings around the furnace doors and thence into the furnaces. The
draught for the furnaces is thus an induced draught and the air is moreover heated
by the escaping hot gases before the said air passes to the furnaces which together
with the tubes containing retarders gives a very efficient and economical combi-
nation. In the drawing I have shewn two of the tubes in section illustrating in
the one case a plain tube with a retarder in it and in the other case an internally
ribbed or "serve tube with a retarder in its central space. These tubes with
retarders are shewn as being used as the boiler tubes E but they may also be used
for the nests of tubes D if desired: If it be desired that the hot gases shall pass
through the tubes and the air around them then in place of the openings as
described the casings B' will have an 'opening into the end chambers above the
compartments C into which chambers one end of each of the tubes will; open the
other ends of the, tubes opening into the uptake and the casings in which the tubes
are contained will have at the uptake end an opening for the inlet of air and at the
other end an opening into the casings C. The uptake F is provided so that it can
be used when desired with natural draught only when the valve g is closed and the
valve i is opened., In normal working with the induced draught the valve is of
course closed and the valve g opened.
Although I have shewn two furnaces in the drawing the invention may be
applied also to single furnaces or furnaces in other number.
+
Lt.
I do not limit myself to the particular form of retarders shewn for instance they
may be in the form of a tube with the fire box end thereof closed.
'
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim'is':
ic
.I.
In connection with tubular steam boilers and their furnaces the combination of
firstly, a fan or device for, creating an induced draught, secondly, the passages for
the products of combustion from the furnace and for the incoming air so that the
มง

page_text: said air is heated by the said products and thirdly, internally ribbed or plain tubes
provided with a retarder or retarders all substantially as hereinbefore described and
illustrated by the accompanying drawings.
Dated this 28th day of December 1892.
J. H. JOHNSON & Co.,
Agents.