IMPROVEMENTS IN GENERATING STEAM FOR MARINE PURPOSES.
Year: 1857

page_text: LETTERS PATENT to William Muir, of Glasgow, in the County of
Lanark, North Britain, Engineer, for the Invention of "IMPROVEMENTS
IN GENERATING STEAM FOR MARINE PURPOSES.".
Scaled the 30th June 1857, and dated the 5th March 1857.
PROVISIONAL SPECIFICATION left by the said William Muir at the Office
of the Commissioners of Patents, with his Petition, on the 5th March
1857.
I, WILLIAM MUIR, of Glasgow, in the County of Lanark, North Britain,,
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN GENERATING STEAM FOR MARINE PURPOSES," to be as follows, that is
to say :-
This Invention relates to the economising of the fuel used for working
marine steam boilers by means of a peculiar mode of heating the feed water
of the boilers prior to its admission into into the boilers. According to these
improvements, the smoke box of the boiler, or that part thereof where the
heated currents escape in their progress to the chimney or funnel, is fitted up
with a coil or coils or other arrangements of water pipes. These pipes are
fitted up in such a manner that they are fully and completely exposed to the
effect of the escaping heat from the furnace and flues. The feed water for
supplying the boiler is supplied into one end of this arrangement of pipes,.
and after passing through them it escapes in a heated condition at the other.

page_text: end in readiness for being fed into the boiler for the generation of steam in
the usual manner. In this way the feed water is highly heated preparatory
to its being converted into actual steam in the boiler by what would other-
wise be waste heat, and hence considerable economy in fuel is secured in a
very simple manner.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Muir in the Great Seal Patent Office on the
5th September 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
MUIR, of Glasgow, in the County of Lanark, North Britain, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of March, in the year of our Lord One
thousand eight hundred and fifty-seven, in the twentieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto I, the said
William Muir, Her special license that I, the said William Muir, my execu-
tors, administrators, and assigns, or such others as I, the said William
Muir, my executors, administrators, or 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 Invention for "IMPROVEMENTS IN GENERATING
STEAM FOR MARINE PURPOSES," upon the condition (amongst others) that I, the
said William Muir, 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 Muir, do hereby declare the
nature of my said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following state-
ment in writing, reference being had to the accompanying Drawings, and to
the letters and figures marked thereon that is to say:
My said Invention relates to the economising of fuel used for working
marine steam boilers by means of a peculiar mode of heating the feed water
of the boilers prior to its admission into the boilers for the production of

page_text: steam. According to these improvements, the smoke box of the boiler, or
that part thereof where the heated currents escape in their progress to the
chimney or funnel, is fitted up with a coil or coils or other arrangements of
water pipes. These pipes are fitted up in such a manner that they are fully
and completely exposed to the effect of the escaping heat from the furnace and
flues. The feed water for supplying the boiler is supplied into one end of
this arrangement of pipes, and after passing through them it escapes in a
heated condition at the other end in readiness for being fed into the boiler for
the generation of steam in the usual manner. In this way the feed water is
highly heated preparatory to its being converted into actual steam in the
boiler by what would otherwise be waste heat, and hence considerable
economy in fuel is secured in a very simple manner.
And in order that my said Invention may be properly understood I shall
now proceed to describe the illustrative Figures on the explanatory Sheet of
Drawings, which I have hereunto appended for the purpose of showing cer-
tain modifications under which my improvements may be judiciously carried
out in practice.
Figure 1 on my Sheet of Drawings is a sectional elevation of a marine steam
boiler, forming one of a pair of such boilers working in concert, as arranged
and fitted up according to my said improvements. Figure 2 on the same
Sheet is a corresponding elevation of the boiler at right angles to Figure 1.
that is to say, as looking upon the furnaces, parts of the boiler being removed
for the purpose of more clearly showing my improved arrangements; the
actual details of the furnaces in this boiler are of the usual kind, except at
the back thereof. There is in each case a brick structure A, having within it
a draught thoroughfare or duct B, through which atmospheric air passes from
beneath the grate or furnace bars in the direction of the arrows, so as to
become heated in its course, and enter the body of the furnace at the throat,
thus melting and mingling with the gaseous matters evolved from the burning
fuel, so as to aid in their effectual and economical combustion. From this
part the draught current passes along the back up-take flue, and thence enters
the back ends of the flue tubes C, emerging at the other end in the smoke
box D, where the heating pipes or tubes E are placed. These pipes may be
arranged in various ways, but in the present instance they are formed into
several parallel rows in a vertical plane, elbow bends being employed for
effecting the continuity of the straight lengths. This piping is sustained by
wrough iron clampholders F, attached to the smoke box. The feed water
from the hot well of the engines is forced by the pump in the usual manner
along the horizontal pipe G, whence it passes up the vertical pipe E, the

page_text: upper end of which is connected to the outer end of the bottom length of
pipe forming the heating arrangement in the smoke box. From this point
the water passes through the entire length of pipes, running along the straight
portions and round the bends, as indicated by the arrows, until it reaches the
top length of piping. From the outer end of this it descends by a short bend,
which passes out through the side of the smoke box and enters the lower part
of the boiler by a junction at I. The vertical portion H of the inlet pipe for
the feed water has also attached to it a self-acting valve branch J, opening
into a valve chest K, containing a hinged valve L, the downward slope of
which valve is directed towards the inlet of the water. The other end of this
valve chest opens into the lower part of the boiler at M. So long as the
engines are running, and the boilers continue to receive their supplies of feed
water, the inlet pressure of this feed water keeps the valve L closed, so that
the actual direction of the feed current is through the heating pipes, in the
manner in which I have herein-before described, and the water takes up the
otherwise waste heat of the smoke box prior to entering the boiler; but
whenever the engines cease to run, and feed water is no longer pumped into
the boiler, the valve L opens owing to the change in the internal condition
of the water, and it is this reversing of the action which causes a constant
current to be kept up through the heating tubes independent of the forcing
action of the feed. So long of course as the feed water is being forced in, as
herein-before described, a proper current is kept up through the heating tubes,
and to keep up a circulation when feed water is not going into the boiler, it
becomes necessary to make special provision in the details of the arrange-
ments. For this purpose the external bend on the pipe immediately above
the junction I, where the water enters the boiler, has attached to it the lower
end of a small pipe N, on which pipe is a stop-cock O for controlling the
communication between the terminal portion of the boiler feed pipe, and the
upper or steam portion of the boiler, as at P. When the engine is stopped,
the valve L opens and the water ascends the pipe N, and passes into the
boiler at P just above the water line. To the pipe N a thermometer may be
attached for the purpose of indicating the temperature of the feed water.
By means of the arrangement of the self-acting valve L and the pipe N the
circulation of the water in the pipes E is kept up, whether the pumps are
working or not, and without requiring any attention on the part of the
engineer or attendants. The water-heating pipe C may be fitted in any other
part of the boiler, or in the furnace, the flues, or smoke box, than that shown
in my Drawing, but so that the heating pipes may intercept or absorb the
heat that would otherwise pass off unused.
In addition to the advantage

page_text: obtained in heating the feed water of the engine, the heating pipes prevent
the flame from ascending the up-take, thereby tending to the preservation of
the boiler itself as well as economising fuel.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, I may observe, in conclusion, that I do not confine or restrict
myself to the precise details or arrangements which I have had occasion to
describe or refer to, as many variations may be made therefrom without
deviating from the principles or main features of my Invention; but what I
consider to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent, is,-
First, the system or mode of heating the feed water for the supply of steam
boilers, by causing the water to flow through pipes, as herein-before described.
Second, the system or mode of causing the feed water to circulate through
the heating pipes, by means of a self-acting valve arrangement, as herein-before
described.
Third, the use and application of water-heating pipes, fitted and arranged
either in the boiler, the furnace flues, or smoke box, for the purpose of heating
the feed water for the supply of steam boilers, as herein-before described.
In witness whereof, I, the said William Muir, have hereunto set my
hand and seal, this Fourth day of September, One thousand eight
hundred and fifty-seven.
WILLIAM MUIR. (L.S.)