and apparatus for superheating steam for all purposes
Year: 1888

page_text: I, ROBERT SHACKLETON, of Borongh Paper Mills, North Wing, Bradford, in the
County of York, Paper Manufacturer, do hereby declare the nature of this invention
to be as follows:-
This invention relates to certain improvements in the method of and apparatus for
superheating steam for all purposes.
In a boiler for the purpose of raising steam, there is a space between the water line
and the crown of the boiler called the steam space; from this reservoir the steam is
drawn for the generation of motive power and other purposes. It is well known
in contra-distinction to what
that the steam drawn therefrom is as a rule "wet steam
is known as "dry steam." It is very desirable that steam for power and almost all
other purposes should be dry, on the ground both of economy and efficiency.
22
The object of my invention is to produce dry steam in the first instance within the
boiler as at present constructed; in the second, by encasing the steam pipes by means
of heated pipes; the third is heating the steam by the insertion of heating pipes
within the steam pipes; fourth by the passage of the steam from the boiler to the
engine or other apparatus through a superheated vessel such as feed water is now
heated in; and fifth by surrounding the cylinder by the ordinary steam jacket now in
use, and heating the same by my improved method.
I accomplish my object by drawing from the atmosphere, air by means of an
injector, forcing the same cold through a series of pipes placed in convenient positions
in the main flues of a boiler, where can heat the air so injected up to a temperature
beyond that of the steam in the boiler, and then I carry the same through coils or lines
of pipes placed within the steam space of the boiler; or I pass the steam through
pipes surrounded by pipes containing the hot air; or I pass the hot air through pipes
surrounded by steam; or I pass the steam from the boiler to engine or other apparatus
through a receptacle such as a feed water heater wherein the heated air is brought
by means of pipes passing in any convenient manner through such receptacle in

page_text: indirect contact with the heated air; or I surround the cylinder of the engine with
an ordinary steam jacket, but in lieu of steam I circulate the heated air, and by these
means I am enabled to superheat the steam for all purposes where dry steam is
desired.
In the case of an engine supplied by steam heated in any of the above methods,
its efficiency is greatly enhanced, not only in the cylinder itself, but a far better
vacuum is obtainable under these conditions than by other means.
JOHN WAUGH,
Agent.
COMPLETE SPECIFICATION
Improvements in the Method of and Apparatus for Superheating
Steam.
I, ROBERT SHACKLETON, of Borough Paper Mills, North Wing, Bradford, in the
County of York, Paper Manufacturer, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :—
In a boiler for the purpose of raising steam there is a space between the water line
and the crown of the boiler called the steam space; from this reservoir the steam is
drawn for the generation of motive power and other purposes. It is well known
that the steam drawn therefrom is as a rule "wet steam," in contra-distinction to
what is known as 16
dry steam."
The primary object of my invention is to ensure the supply of dry steam to the
cylinder of a steam engine. It is well known that cylinders are now supplied with
steam which is more or less a mixture of steam and water, and it is to this fact
that the greatest loss of efficiency is attributable even in an engine of good
design.
In theory a certain weight and quality of coal has a definite efficiency. In practice
the actual consumption exceeds the theoretical, and the difference is equal to
some 25 to 40 per cent., this loss is for the most part attributable to cylinder
condensation.
Various well known modes have been adopted to prevent this loss, and even James
Watt was fully alive to the desirability of preventing it, and adopted a means
whereby such loss was minimized by jacketing the cylinder, and admitting into this
jacket steam from the boiler in order to keep up the temperature; and more recently

page_text: cylinders have been covered with a non-conducting substance with the object of
preventing loss by radiation, but with such appliances we still have cylinder
condensation.
The steam when it leaves the boiler is more or less saturated with water; there is
further condensation within the connecting pipes, between the boiler and engine;
there is condensation on the admission of steam to the cylinder and loss during the
stroke; and in spite of the ordinary system of jacketing in use hitherto, and the
covering of the outer casing of the cylinder with non-conducting substance, there is
serious loss from radiation.
By my improvement I am enabled to dry the steam within the boiler and pipes
by heated air of a temperature much higher than that of the steam from the
boiler itself, and by these means, to supply the cylinder with drier steam, and
further to reduce very materially the loss of efficiency bitherto due to cylinder
condensation.
I accomplish my object by drawing from the atmosphere by means of an injector,
rotary blower, fan, or other well known agency used for displacing air, and forcing
the same through a coil or series of pipes placed in a convenient position in the flue
of a boiler or other suitable heated chamber, where the air injected into, and passing
through the pipes can be heated up to a temperature beyond that of the steam in the
boiler; the coil or series of pipes before mentioned being continued, and may be
passed through the boiler in any convenient manner within the steam space above the
water level, by which the steam is superheated, and thereby made materially drier
whilst within the boiler, than is the case with boilers as hitherto constructed.
The steam may be superheated and dried by enclosing the steam supply pipes of
the engine within pipes of larger diameter, through the latter of which hot air
produced in the manner as hereinbefore described is conducted, thus imparting
additional heat to the steam, and drying the same.
In order to reduce the condensation of steam within the cylinders of steam engines,
I surround the cylinder by a jacket of the ordinary construction; and in lieu of
circulating steam therein, atmospheric air heated in the manner as before described
is circulated through the jacket, and by it being heated to a very much higher
temperature than that of the steam in the boiler, a greater degree of heat passes
through the cylinder casing to the steam in the interior operating the piston; thereby
minimizing the condensation therein; therefore increasing the efficiency of the engine
in proportion to the dryness of the steam.
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,
The method hereinbefore described of drying steam by first heating atmospheric
air to a high temperature and applying it to a boiler, steam pipes, or engine cylinder,
substantially in the manner as herein before set forth.
Dated this 18th day of In 1000
JOHN WAUGH,
Agent.