Improvements relating to the Superheating of Steam, and the Heating of the Air Supply to Tubular Boilers, by Means of the Products of Combustion.
Year: 1895

page_text: Date of Application, 19th Nov., 1895
Complete Specification Left, 19th Aug., 1896-Accepted, 3rd Oct., 1896
PROVISIONAL SPECIFICATION.
Improvements relating to the Superheating of Steam, and the
Heating of the Air Supply to Tubular Boilers, by Means of
the Products of Combustion.
I, GEORGE WILLIAM HAWKSLEY, of the Brightside Boiler Works, City of
Sheffield, Boiler Manufacturer, do hereby declare the nature of my invention to
be as follows:-
My invention relates to the arrangement and combination of mechanism in
connection with tubular boilers, for superheating the steam, and also for heating
the air supplied to the furnaces of same.
The object is to utilise as much as possible the flame and heated gases after
they have passed through the tubes of the boiler, first, to enable the steam to be
superheated to its highest limit, and to be supplied at any desired degree of
saturation, and second, to warm the supply of air to the furnace.
In carrying out my invention I propose to receive the heated gases after they
have passed from the flue into the combustion chamber at the back of the boiler,
and through the tubes into smoke boxes on each side at the front of boiler from
which they pass upwards into horizontal superheaters situated on each side of and
immediately above the boiler.
They consist of a number of steam pipes opening into enclosed ends and being
in communication with the main steam pipes.
After passing through the superheaters the gases descend round the boiler
surface passing round and between a cluster of air tubes to a flue, and from thence
to the chimney.
The steam space at each end of the superheaters is connected with the main
steam supply pipe, which has also direct communication with the boiler, and I
provide a number of stop valves so arranged that steam may be passed direct from
the boiler to the engine, or it may be passed direct from the superheaters, or if
preferred a mixture of the superheated steam and saturated steam from the boiler
may be had in any desired proportions.
The air supply is admitted at the back of the boiler into a space formed by
covering the brickwork of the combustion chamber with a casing of metal and
leaving a space between. The mouth or entrance is at the top from which the air
passes down over the brickwork into an enclosed chamber, then through a series
of horizontal air-tubes before mentioned to the front of boiler and into the space
under the firebars.
To increase the draught in the flue, when the natural draught is not strong
enough, I arrange a fan or other blower, and with the aid of valves I can when
desired divert the direct course to the chimney, and cause it to pass through the
fan or blower and by this means I can increase the velocity of the draught to
suitable degree.
Dated the 16th day of November 1895.

page_text: Improvements relating to the Superheating of Steam, and the
Heating of the Air Supply to Tubular Boilers, by Means of
the Products of Combustion.
I GEORGE WILLIAM HAWKSLEY of the Brightside Boiler Works, in the
City of Sheffield Boiler Manufacturer do hereby declare the nature of this
invention and in what manner the same has to be performed, to be particularly
described and ascertained in and by the following statement:—
My invention relates to the arrangement and combination of mechanism in
connection with tubular boilers, for heating the air supplied to the furnaces for
combustion and for superheating the steam.
The object is to utilise as much as possible the flame and heated gases after they
have passed through the tubes of the boiler, to enable (in the first place) the steam
to be superheated to its highest limit, and to be supplied at any desired degree of
saturation, and in the second place to heat the air supply to the furnaces.
The method of carrying the invention into practice is illustrated in the sheet of
drawings annexed hereto.
Fig. 1, is a longitudinal section of a tubular boiler constructed according to my
invention.
Fig. 2, halfcross sections of same through 1. 2 and 3. 4.
Fig. 3, front view of boiler.
Fig. 4, plan of Fig. 1, with part removed.
The general construction and usual details of the boiler illustrated, will be
understood by practical men, I shall therefore confine my description to the
improvements, premising that similar letters of reference refer to similar parts in
any of the figures in which they may occur.
The heated gases after passing from furnace flue A, into the combustion
chamber B, and through the tubes C, into smoke boxes D, in front of the boiler,
pass upwards through a short flue and the opening D² see Fig. 4 into horizontal
superheaters E, which are situated on each side of and immediately above the
boiler.
The consist of a number of steam pipes F, which open into enclosed end
chambers G, which are in communication with the main steam pipes H.
After leaving the superheaters by the opening E' the gases descend round the
lower part of the boiler surface through an open space left in the brickwork then
pass through, (that is around and between) a cluster of air warming tubes I,
and finally through the openings S into a flue T leading to the chimney stack J.
The steam spaces or chambers G, at each end of the superheaters E, are as
before mentioned, connected with the main steam pipes H, which have direct
communication with the boiler, and a number of stop valves V, V, V³, so arranged
that by opening V₁, and closing V2, and V³, steam may be passed direct from the
boiler to the engine, or by closing V₁, and opening the others, all the steam will
be passed through the superheaters, or if a mixture of the superheated and
saturated steam is required, the valves may be all opened in the desired
proportions.
The air supply for combustion is admitted at the back of the boiler into a
space K, formed by covering the brickwork of the combustion chamber B, with a
casing of metal L, leaving the space K, between the two, an entrance being made
at the top marked M.
The air entering at the mouth M, passes down over the heated brickwork N,
into an enclosed chamber then through a series of horizontal open end tubes I,

page_text: before mentioned, to the front of the boiler and into the space P, under the furnace
fire bars.
To increase the draught in the flues when the natural draught is not strong
enough, I arrange a fan Q, of any suitable construction, in communication with
the flue and with the chimney J, and by the aid of a valve R, to close the
chimney and one to cut off the fan marked W, I can divert the course of the
draught and cause it to pass through the fan at an increased velocity.
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 :-
1. The improvements for the superheating of steam in connection with tubular
boilers, as herein before described and set forth.
2. The improvements for the heating of air supplied to the furnaces of steam
boilers as herein before described and set forth.
3. In combination with the superheaters of steam boilers as hereinbefore
described, the arrangement of the steam pipes H, and the valves V1, V2, and V³,
as described.
Dated the 15th day of August 1896.
ROBT. F. DRURY, C.P.A.,
Bank Buildings, George Street, Sheffield, Agent for Applicant.