IMPROVED APPARATUS FOR SUPERHEATING STEAM
Year: 1860

page_text: LETTERS PATENT to William Edward Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Civil Engineer, for the
Invention
IMPROVED APPARATUS FOR SUPERHEATING STEAM. A com-
munication from abroad by Benjamin Normand, of Havre, in the Empire
of France.
Sealed the 27th September 1860, and dated the 10th April 1860.
PROVISIONAL SPECIFICATION left by the said William Edward Newton
at the Office of the Commissioners of Patents, with his Petition, on the
10th April 1860.
I, WILLIAM EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane,
in the County of Middlesex, Civil Engineer, do hereby declare the nature of
the said Invention for "IMPROVED APPARATUS FOR SUPERHEATING STEAM,"
to be as follows:-
This Invention relates to a novel method of superheating steam, principally
for the purpose of obtaining motive power, by which many disadvantages
consequent upon the usual method of superheating are avoided, such for
instance, as irregularity of temperature, oxidation of the parts exposed to heat
and rapid deterioration of the working parts from the drying of the lubricant
employed by reason of the overheating of the steam.
In carrying out this Invention, high-pressure steam is employed as the
medium for superheating common or low-pressure steam in its passage from
the boiler to the working cylinder of the engine. A small auxiliary boiler,
and furnace situate below the main boiler, or in any other convenient situation

page_text: are employed for the purpose of generating high-pressure steam. This
steam passes into a cylindrical or other chamber provided with a series of
metal tubes through which the common steam from an ordinary boiler is
caused to pass. In its passage through the tubes in the superheating
chamber, the common steam takes up caloric from the atmosphere of high-
pressure steam surrounding the tubes. The water of condensation in the
superheating chamber from the high-pressure steam passes back into the
high-pressure boiler to be again converted into high-pressure steam.
It will now be understood that the bigh-pressure steam is only the vehicle
for conveying the caloric from the fire to the common or low-pressure steam
instead of allowing the latter to be acted upon direct by the heat from the
furnace. The cylindrical or other shaped superheating chamber is provided
with safety valves, so that the pressure therein may never rise to a dangerous
point. If desired the superheating chamber may be enclosed within the
casing of the boiler, which generates the common steam, or the superheating
chamber and common steam chest may be arranged in any other convenient
manner provided the steam just before entering the working cylinders, be
caused to pass through the superheating chamber, that is supplied with high-
pressure steam.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Edward Newton in the Great Seal Patent Office on
the 10th October 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM.
EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the County
of Middlesex, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent bearing date the Tenth day of April, in the year of our Lord
One thousand eight hundred and sixty, in the twenty-third year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said William Edward Newton, Her special license that I, the said
William Edward Newton, my executors, administrators, and assigns, or such
others as I, the said William Edward Newton, my executors, administrators,
and assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United Kingdom
of Great Britain and Ireland, the Channel Islands, and Isle of Man, an

page_text: Invention for "IMPROVED APPARATUS FOR SUPERHEATING STEAM," being a commu-
nication from abroad upon the condition (amongst others) that I, the said
William Edward Newton, by an instrument in writing under my hand and seal,
should particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE; that I, the said William Edward Newton, do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the Drawing hereunto annexed,
and to the letters and figures marked thereon (that is to say): -
The improvements, which form the subject of the present Invention, relates
to a novel method of effecting the operations of drying and superheating steam >
before applying it to motive-power purposes, the object being to secure great
economy in the expenditure of steam, and consequently in the quantity of fuel:
employed.
Many arrangements of apparatus have been proposed, and several are now
employed to effect the superheating of steam. These arrangements consist of
tubes submitted to the action of a fire or of heated gases, derived from the
steam boiler furnaces.
The superheating apparatus hitherto used present in various degrees the
following inconveniences, vizt.,--First, irregularity in the degree to which the
steam is superheated, by reason of variations of temperature in the heated
gases, and by variable obstacles to the transmission of heat, as deposits
of soot upon the heat-absorbing surfaces. When these deposits of soot
take fire, there is then an excessive and injurious increase of temperature.
Secondly, oxidation and rapid destruction of the parts exposed to heat
which can only be made of iron, by reason of the high temperature to
which they are exposed. Another inconvenience is parting of the joints
from considerable and unequal expansion. These disadvantages take place
even under ordinary circumstances, every time that the current of steam
being interrupted, the parts acquire from the heated gases a tempera-
ture ranging generally from three hundred to four hundred degrees.
(centigrade).
Thirdly, drying of the working parts or rubbing surfaces of the engine
when the steam attains too high a temperature causing excessive wear and
tear, and consequently increased friction and loss of power.
These disadvantages are still further increased by the scales of oxide.

page_text: of iron, which are detached from the sides of the superheating apparatus
and carried into the steam chest and cylinders along with the steam.
In the arrangement forming the subject of this Invention, and which will
be now described, the heat is transmitted to the heating surfaces in a
somewhat indirect manner by means of a small quantity of high-pressure
steam. It will therefore be understood that the high-pressure is only
employed as the medium or vehicle for conveying the heat to the low-pressure
steam and facilitating and regulating its transmission.
In the accompanying Drawing the apparatus employed for carrying out this
Invention is represented in longitudinal sectional elevation at Fig. 1, and in
transverse vertical section at Fig. 2, drawn to a scale of one-tenth the real size.
It is ordinarily composed of two distinct parts, viz. :-
First, a small high-pressure boiler A, A, made tubular, by preference, and
constructed in the same manner as ordinary locomotive boilers.
Secondly, a cylindrical chamber B, situate above the high-pressure boiler,
and made to communicate with it by means of two large pipes C, C. This
upper chamber or boiler is provided inside with small tubes D, D, D, which'
offer a considerable heating surface.
All the space comprized between the exterior surface of the tubes D, D, D,
and the interior of the chamber B, B, is filled with the high-pressure steam
formed in the small boiler below. The body of steam at low or medium
pressure which is to be supplied to the engine, is distributed throughout the
interior of all the tubes D, and after passing through their whole length makes
its exit at a temperature nearly equal to that of the high-pressure steam,
which circulating around the outside of the tubes superheats the steam con-
tained within the tubes. The steam condensed on the outer surface of the
tubes D, returns immediately into the small boiler through the passages C, C,
to be again converted into steam. The water level is thus maintained in the
boiler A without any variation, except that occasioned by a slight escape
through the valves. It will now be understood that the high-pressure steam
is merely the vehicle for the transmission of the caloric to the steam required
to be superheated. The valves which serve to limit the pressure prevent at
the same time any excessive elevation of temperature. The body of water in a
state of ebullition forming as it does a reservoir of heat, also serves to correct
any irregularities of temperature in the combustion chamber.
As on part of the apparatus can be at any time heated to a temparature above
one hundred and sixty, or at the most one hundred and eighty degrees
centigrade (for a pressure of ten atmospheres), the preservation of the joints
and the substance which composes the heating surface is ensured. The

page_text: heating surfaces may be constructed either of copper or an alloy of that
metal, which will undergo little or no oxidation, and are not subject to the
disadvantages incident to superheating apparatus as ordinarily constructed.
Another advantage of this system is, that as the superheating may be
effected just prior to the steam entering the cylinders, any condensation which
may take place in the passages from the boiler is effectually removed, and no
portion of heat imparted to the steam can be lost up to the time at which the
duty of the steam is completed.
It is known that as the calorific capacity of steam and also its density are
very small, sensible increase of temperature will only represent very small
quantities of heat. Instead of dividing the superheating apparatus into two
distinct parts, the one for vaporization and the other for the transmission of
heat, the distinct functions of these two parts might be performed in a single
casing; the apparatus would then be of the form of an ordinary boiler, the
steam chamber of which would be provided with tubes, through which the
steam to be heated would pass.
If when using the first arrangement it should not be found convenient to
set the small boiler immediately below the steam pipe of the motive engine,
this small boiler might be otherwise placed, and connected with the heating
apparatus by suitable pipes, care being taken that such a difference of level
was retained as to ensure the return of the water of condensation to the
vaporizing apparatus.
Having now set forth the nature of the Invention of "Improved Apparatus
for Superheating Steam," as communicated to me by my foreign correspondent,
and explained the manner of carrying the same into effect, I wish it to be
understood that under the above in part recited Letters Patent, I claim the
construction and use of apparatus operating in the manner and for the purpose
above described.
In witness whereof, I, the said William Edward Newton, have hereunto
set my hand and seal, the Tenth day of October, in the year of
our Lord One thousand eight hundred and sixty.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
W. E. NEWTON. (L.S.)