IMPROVEMENTS IN CUPOLA AND OTHER FURNACES
Year: 1866

page_text: PROVISIONAL SPECIFICATION left by Samuel Chatwood and John
Sturgeon at the Office of the Commissioners of Patents, with their
Petition, on the 5th May 1866.
We, SAMUEL CHATWOOD, of Bolton, in the County of Lancaster, Safe and
Lock Engineer, and JOHN STURGEON, of Burley, near Leeds, in the County
of York, Consulting Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN CUPOLA AND OTHER FURNACES," to be as
follows:-
Our Invention has for its object improvements in cupola and other
furnaces, and consists mainly in the application thereto of certain apparatus
for producing a jet or jets of steam so..applied as to produce a partial
vacuum, and thereby induce a current of air either in the funnel or chimney
leading from the furnace, suitable openings being provided in the lower part
of the furnace to admit the air, whether hot or cold, required to support
the combustion of the fuel or in the tuyere pipes, or at any other convenient
place.
For this purpose we attach to the upper part of the furnace or cupola
suitable apparatus for generating steam instantaneously, as described in the
Specification of a Patent granted to the herein-named John Sturgeon, dated,
10th October 1865, and, numbered 2604, namely, by the injection of
regulated quantities of water in a divided state into a suitable steam chamber,
heated chiefly by the waste beat from the furnace, from which chamber the
steam passes through a suitable jet pipe into the funnel or chimney, and in

page_text: order to obtain the necessary heat in the steam generator at the commence-
ment before the furnace has attained its requisite heat we apply a suitable
apparatus for carrying a temporary fire at the upper part of the furnace by
which steam may be raised for the purpose stated until the furnace has
attained sufficient heat to generate the steam as required without the aid
of the auxiliary fire, which may then be allowed to fall down into the furnace
by withdrawing the support of the fire-bars or by tilting the apparatus, after
which the apparatus may be withdrawn, leaving the steam generating
apparatus to the action of the waste heat only from the furnace. A small
engine working the feed pumps of the steam generator may be driven by
steam from the same apparatus that is used to generate steam for the furnace
or cupola, the exhaust steam from which engine may also be driven into
the chimney or funnel so as to further increase the force of the draught.
The feed water may be taken by these pumps from a reservoir placed under
the stage or platform; or in any other, convenient situation. Or, in place of
the arrangement of apparatus above described, an ordinary steam boiler may
be applied, in which the steam is first raised by the application of a tem-
porary fire at the upper part of the furnace, which fire may be afterwards
withdrawn or allowed to fall into the furnace when the waste heat of
the latter has become sufficient to keep up the steam in the said boiler.
We would here remark that we are aware it has been before proposed to
-supply air to furnaces by means of a jet of steam so applied as to produce a
partial vacuum and thereby induce a current of air, and, moreover, that it has
also been proposed to employ the waste heat from the furnace to generate the
required steam from water contained in suitable chambers at the upper part
of the furnace, all which plans, however, necessitated the use of a separate
-steam boiler, whether to produce and maintain the jet of steam or to produce
it at the commencement until there should be sufficient waste heat to generate
steam by the furnace itself.
In the case of smiths' hearths, forges, and small furnaces the waste heat
may be in like manner employed to generate steam, which may either be
used in the form of a jet or jets applied so as to induce a current of air or to
work a fan or other apparatus employed to produce a current of air without
burning additional fuel for that purpose. Also in furnaces or converters:
employed for converting cast iron into steel by the use of superheated steam,
and in other similar cases, we employ the waste heat from the furnace in the
manner and for the purpose herein described.
.
Another part of our Invention consists in using a weighted valve or plug!
(which also serves the purpose of a safety valve) applied to the jet pipe,.by

page_text: which the pressure of the steam may be regulated and varied at will, and
consequently the velocity with which it issues from the jet, thereby con-
trolling and regulating the force of the draught in the chimney or funnel.
This is also accomplished by suitable gear applied to regulate the speed of
the engine or stroke of the pumps, and consequently the pressure of steam in
the generator.