IMPROVEMENTS IN HOT-BLAST STOVES
Year: 1882

page_text: LETTERS PATENT to Edward Alfred Cowper, of No. 6, Great George Street,
Westminster, in the County of Middlesex, for an Invention of "IMPROVEMENTS
IN HOT-BLAST STOVES."
PROVISIONAL SPECIFICATION left by the said Edward Alfred Cowper at
the Office of the Commissioners of Patents on the 31st January 1882.
EDWARD ALFRED COWPER of No. 6 Great George Street Westminster in the
County of Middlesex. "IMPROVEMENTS IN HOT BLAST STOVES."
My improvements relate to that description of stoves commonly called pipe
stoves in which the cold blast is passed into a series of pipes and comes out heated
to such a temperature as the pipes are capable of sustaining or to a somewhat
lower temperature, but in all such cases the temperature is limited by the nature
of the pipes. Now I am aware that it was attempted to obtain high temperatures
of blast by firebrick regenerative hot blast stoves, such as are described in Patent
No. 1404 of 1857 granted to myself and such high temperatures are now commonly
obtained at the present day by the Inventions described in Patent No. 34 of 1870
& 1623 of 1874. Experiments were also made by myself in 1863 with firebrick
pipes, with the view of obtaining a high temperature of blast, but such pipes
failed owing to the firebrick pipes leaking to a large extent, as they were not
capable of retaining the pressure at which the blast is required to be used, for
blowing blast furnaces. I am aware that the metal platinum which would bear
this temperature and pressure, is at present far too expensive to be used for the
purpose of making pipes for hot blast pipe stoves, but I have discovered that
steel pipes are capable of resisting the pressure required and are well able to
resist the high temperature to which it is desirable to heat the blast, and my
present Invention consists, in the use of steel pipes and the mode of applying the
same, in the construction of hot blast pipe stoves, for obtaining very high tempera-
tures of blast for blast furnaces, whether they are used by themselves or in

page_text: addition to castiron pipe stoves. In the latter case the cast iron pipe stoves would
be used first to beat the blast to as high a degree as they are capable of with-
standing, after which the blast would be heated to a much higher degree such as
steel pipes are capable of withstanding. I prefer to employ the waste gases from
the top of the blast furnace in combustion, to heat such steel pipes to the very high
temperatures desired, such pipes being made either of cast steel, or wrought steel
or I use other gaseous or solid fuel for the purpose of heating such steel pipes.
For the highest temperature I prefer to use steel containing but a small proportion
of carbon, as such steel will stand a higher temperature than steel containing a
large proportion of carbon.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edward Alfred Cowper in the Great Seal Patent Office on the
29th July 1882.
EDWARD ALFRED COWPER of No. 6 Great George Street Westminster in the
County of Middlesex. "IMPROVEMENTS IN HOT BLAST STOVES."
My improvements relate to that description of stoves commonly called pipe
stoves in which the cold blast is passed into a series of pipes and comes out heated
to such a temperature as the pipes are capable of sustaining or to a somewhat
lower temperature, but in all such cases the temperature is limited by the nature
of the pipes. Now I am aware that it was attempted to obtain high temperatures
of blast by firebrick regenerative hot blast stoves, such as are described in the
Specification to Patent No. 1404 of 1857 granted to myself and such high tempera-
tures are now commonly obtained at the present day by the Inventions described
in the Specifications to Patents No. 34 of 1870 and No. 1623 of 1874, but by this
arrangement, although a very high temperature of blast may be obtained when
the heated stove is first brought into use, this heat is not maintained uniform
owing to the gradual cooling of the stove. Experiments were also made by myself
in 1863 with firebrick pipes, with the view of obtaining a high temperature of
blast, but such pipes failed owing to the firebrick pipes leaking to a large extent, as
they were not capable of retaining the pressure at which the blast is required to
be used for blowing blast furnaces. I am aware that the metal platinum which
would bear this temperature and pressure, is at present far too expensive to be
used for the purpose of making pipes for hot blast pipe stoves, but I have discovered
that steel pipes are capable of resisting the pressure required and are well able to
resist the high temperature to which it is desirable to heat the blast, and my
present Invention consists in the use of steel pipes and the mode of applying the
same in the construction of hot blast pipe stoves, for obtaining very high tempera-
tures of blast for blast furnaces, whether they are used by themselves or in addition
to cast iron pipe stoves. In the latter case the cast iron pipe stoves would be used
first to heat the blast to as high a degree as they are capable of withstanding, after
which the blust would be heated to a much higher degree such as steel pipes are
capable of withstanding. I prefer to employ the waste gases from the top of the
blast furnace in combustion, to beat such steel pipes to the very high temperatures
desired, such pipes being made either of cast steel or wrought steel, or I use other
gaseous or solid fuel for the purpose of heating such steel pipes. For the highest
temperature it may be advisable to use steel containing but a small proportion of
carbon, as such steel will stand a higher temperature than steel containing a large
proportion of carbon.
From what has been described above it will be understood that by employing
steel pipes either alone or in sequence to cast iron pipes, all the advantages of a
blast heated to the very high temperature obtained by the use of a fire brick
stove are secured in conjunction with uniformity of temperature such as is obtained
by a pipe stove.
Having thus described the nature of my Invention and in what manner the same
is to be performed, I claim
First. Constructing hot blast pipe stoves the pipes of which are made of steel.
Second. The combination with a cast iron hot blast pipe stove of a hot blast
pipe stove the pipes of which are made of steel, the said stove being so arranged

page_text: that the blast is first passed through the cast iron stove in order to become heated
to a certain degree and is then passed through the steel stove in order to be heated
to a still higher degree.
In witness whereof I the said Edward Alfred Cowper have hereunto set my
hand and seal this Twenty-seventh day of July in the year of Our Lord
One thousand eight hundred and eighty two.
ייז