CERTAIN IMPROVEMENTS APPLICABLE TO REVOLVING FURNACES, AND CERTAIN METHODS OF UTILISING SUCH FURNACES
Year: 1877

page_text: LETTERS PATENT to Samuel Godfrey, Engineer, and Richard Howson,
Enginec, both of Middlesbrough-on-Tees, in the County of York, for the
Invention of "CERTAIN IMPROVEMENTS APPLICABLE TO REVOLVING FURNACES,
AND CERTAIN METHODS OF UTILISING SUCH FURNACES"
Sealed the 28th March 1877, and dated the 29th January 1877
PROVISIONAL SPECIFICATION left by the said Samuel Godfrey and
Richard Howson at the Office of the Commissioners of Patents on the 29th
January 1877
SAMUEL GODFREY, Engincer, and RICHARD Howson, Engineer, both of
Middlesbrough-on-Tees, in the County of York CERTAIN IMPROVEMENTS
APPLICABLE TO REVOLVING FURNACES, AND CERTAIN METHODS OF UTILISING
SUCH FURNACES"
Our Invention consists in further improvements upon or relating to a former
Invention for which a Patent was granted to us on the 20th of December, 1873,
No 4414, for "Improvements in Gas Furnaces," and also in a new application of
revolving furnaces generally
In the Specification of the aforesaid Patent we state that "we do not confine
ourselves to the employment of any particular kind of gas, but we prefer it to be of
pure quality and to be stored in gas holders, so as to be able to command a pressure
graduated at will"
The first part of our present Invention has reference to the use of a steam jet for
producing the requisite pressure, so that the gas holder may be dispensed with The
jet may be of the ordinary well known construction, but its position must be such
that the injected steam mixed with au must pass through the incandescent mass of
coal or coke with which the retort or gas generator is supplied By this anange-
ment the steam becomes decomposed, as is well understood, and a pressure is set up
in the retort or generator which propels the gas and causes it to issue with the
requisite degree of force at the burner
The second part of our Invention relates to the said burners or tuyeres through
which the jets of flame are injected into the furnace In the aforesaid Specification
of December 20th, 1875, we state that "such burners may be protected by an in-
ternal circulation of water, as practised in blast furnace tuyeres." Our improve-
Panas S1

page_text: ment lins reference to protecting them by an internal circulation of steam instead of
water in order to avoid the danger of explosion fion water getting into the furnace
should a leak occur from any cause in the burne
The thund part of our Invention relates to the general arrangement of ievolving
furnaces, by which we take advantage of the waste gases for heating the au required
for combustion
It is a leading feature of our former Invention, as described in the aforesaid
Specification, that the edge or lip of the revolving chamber is entirely fiee from
contact with any rubbing surface, and that the waste gases are allowed to issue
between the burner and the aforesaid edge or lip The necessity for a chimney in
the ordinary sense is thus dispensed with
According to our present Invention the waste gases are allowed to issue ficely in
precisely the same manner, but they are afterwards made to take a direction
upwards through an opening into a heating chamber which is traversed by a series
of heating pipes before escaping into the atmosphere Through these heating pipes
the air required for combustion is forced in its passage to the buinei
Our Invention as thus described is mainly applicable to the puddling or refining
of iron; but it is also either wholly or in part applicable to other purposes where an
intimate mixture of materials is iequued while in a-heated state, such as in the
manufacture of soda ash and other chemicals.
The fourth part of our Invention relates to the mode of lining revolving furnacos
as applied to puddling purposes, and has reference to the use of Portland or other
hydraulic cement mixed with oxide of non in the formation of such lining
The fifth part of our Invention relates to the application of revolving furnaces
generally as auxiliaries to the Bessemer process
It is well known that in the aforesaid process only pig non of a certain degree of
punity can be employed According to our present Invention we are enabled to use
a certain proportion of pig non of a more mipure and therefore cheaper quality in
the manner following We charge the Bessemer converter with melted pig uion of
good quality as usual, but not to its full complement, and we make up the deficiency
with on which has been puddled, or partially puddled, in a revolving furnace By
this puddling, or partial puddling, the onginal nupurities of the crude pig non
become so fai climinated as not to be injurious to the final average product of the
converter, and by thus employing the revolving furnace as an auxiliary to the con-
verter we are enabled to economise the consumption of pig 11on of a more expensive
class.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the sad Samuel Godfrey and Richard Howson in the Great Seal Patent
Ofhee on the 20th July 1877
SAMULL GODFREY, Engineer, and RICHARD Howson, Engineer, both of
Middlesbrough-on-Tees, in the County of York CERTAIN IMPROVEMENTS
APPLICABLE TO REVOLVING FURNACES, AND CERTAIN METHODS OF UTILISING
SUCH FURNACES"
Our Invention consists of further improvements upon and relating to a former
Invention for which a Patent was granted to us on the 20th of December, 1875,
No 4414, for "Improvements in Gas Furnaces"
In the Specification of the aforesaid l'atent we state that "we do not confine
ourselves to the employment of any particular kind of gas, but we prefer it to be of
pure quality and to be stored in gas holders, so as to be able to command a pressure
at will "
According to our present Invention we use a steam jet for producing the requisite
pressure so that the gas holder may be dispensed with. The jet may be of the
ordinary well known construction, but its position must be such that the injected

page_text: .steam mixed with an must pass through the incandescent mass of coals or other
fuel with which the retort or generator is supplied By this arrangement the steam
becomes decomposed, as is well understood, while at the same time a pressure is set
up in the retort or generator thereby propelling the gas and causing it to issue with
5 the requisite dogiee of force at the burner
Referring to the Drawing hereto annexed, A is the retort or gas generator, con-
sisting of a chamber or oven containing coal or other fuel The exact form or typo
of such oven is not material to this Invention, but the an which is supplied to it for
partial combustion and production of gas is forced in among the mass of incan-
descent fuel by means of the steam Jets B, B In this manner while the steain
becomes decomposed a pressure is set up in the interior and the gas is forced in the
dnection of the arrows along the main C, issuing ultimately at the burner D, whero
it meets with a blast of au from the nozzle E.
In the Drawing the buiner or tuyere is shown at D, as if it were a solid casting
or forging, either of which it may be when the heat of the furnace is not required
to be very great, but in cases in which a high temperature is required we protect
such tuyoies by an internal circulation of steam instead of using water in order to
avoid the danger of explosion in case a leak should occur from any cause in the
buinei oi tuyere
It is a leading feature of our former Invention, as described in the aforesaid
Specification, that the edge or lip of the revolving vessel (maiked F in the Diawing)
15 entnely fiee from contact with any rubbing surface, and that the waste gases aro
allowed to issue between the outside of the burner D and the inside periphery of
the vessel F The necessity for a chimney in the ordinary sense is thus dispensed
with
We now allow the waste gases to issue in precisely the saine manner, but
according to our present Invention they are after wards made to take a direction
upwards through an opening to a chamber which is traversed by a series of
heating pipes before escaping into the atmosphere The whole will be readily un-
derstood on reference to the Diawing where G is the heating chamber (shewn 10
vertical cross section) containing several tows H of heating pipes through which tho
air equned for combustion at the buiner D is forced by mechanical incans, thus
traversing the successive rows of hot pipes until it issues and meets the gas at the
nozzle E at a comparatively high temperature
In the Drawing we have shewn only one form of furnace described by us in the
Specification of the aforesaid Patent of December 20th, 1875, namely, that which is
mounted on trunions and revolves at angle The above recited improvements are
equally applicable to the arrangement by which the furnace revolves horizontally,
whether such horizontal furnace is supplied with two burners, that is to say, one at
each end, as described in our aforesaid Specification, or whether there is a buiner
only at one end and the buint gases are allowed to issue at the other end, in every
case the improvements are consistent with that distinctive feature of our former
Patent, namely, that the end on ends of the furnace revolve without fictional contact
with any opposed surface
In the formation of the lining of revolving furnaces it is usual to employ oxide of
iron It is a feature of our present Invention that we use oxide of 11 on in conibina-
tion with Portland or other hydraulic cement A part of the oxide 15 ground or
used in the state of powder, and it is worked up with water and a small proportion
of hydraulic ceinent to the consistency of mortar The interior of the furnace is
plastered with this material, and while it is in a plastic state lumps of oxide are
embedded in it The whole becomes shortly set into a haid mass and is then ready
for use
The proportion of cement to oxide may vary, one of the former to three of
the latter answeis the purpose, but we do not confine ourselves to any exact
pioportion
We have ascertained that revolving furnaces such as we have thus described are
applicable to other useful puposes besides those described in the Specification of our
aforesaid Patent of December 20th, 1875. They are applicable, for instance, to the
manufacture of od ash and other chemicals, to the roasting of ore, and other

page_text: purposes where an intimate mixture of materials while in a heated state is a
desideratum
We have also ascertained that revolving furnaces generally are applicable as
auxiliaries to the Bessemer process It is well known that in this process only pig
iron of a certain degree of purity can be employed Now, we use the revolving
furnace for refining or purifying pig iron of a commoner and cheaper class, and the
iron so refined or purified, that is to say, either puddled or partially puddled, we
add to the ordinary charge of the Bessemer converter, incorporating the same with
it, by which means we are enabled to a certain extent to economise the con-
sumption of more expensive brands of pig 11on
Having thus described the nature of our said Invention and the mode of carrying
the same into practical effect, we would have it understood that what we claim as
essentially belonging to our Invention is as follows
-
1st. The mode described of obtaining the requisite pressure at the burner by the
application of a steam jet in such a manner that the steam becomes decomposed by
passing through incandescent fuel before it reaches the said burner.
2nd. The method of protecting the tuyeres or burners of revolving furnaces by
means-of a circulation of steam as distinguished from the use of water for a similar
purpose
31d The mode of utilizing the waste gases issuing from revolving furnaces in
heating the an icquired for combustion at the burner
4th The mode of lining revolving furnaces with oxide of iron mixed with
hydraulic cement.
5th The application of our improved construction of revolving furnaces to the
manufacture of chemicals, the roasting of ores, and other purposes where agitation
of materials accompanied with heat is a desideratum.
6th. The application of revolving furnaces as auxiliaries to the Bessemer process,
so as to economise the consumption of more expensive brands of pig iron.
The whole as described.
In witness whereof, I, the said Richard Howson, have hereunto set my
hand and seal, thus Twenty-first day of July, in the year of our Lord
One thousand eight hundied and seventy-seven
RICHARD HOWSON
(LS)
RICHARD HOWSON (LS)