IMPROVEMENTS IN THE CONSTRUCTION OF BOILERS AND APPARATUS CONNECTED THEREWITH
Year: 1853

page_text: LETTERS PATENT to Joshua Murgatroyd, of Heaton Norris, in
the County of Lancaster, Millwright and Engineer, for the In-
vention of "IMPROVEMENTS IN THE CONSTRUCTION OF BOILERS AND
APPARATUS CONNECTED THEREWITH."
Scaled the 23rd March 1853, and dated the 1st February 1853.
PROVISIONAL SPECIFICATION left by the said Joshua Mur-
gatroyd at the Office of the Commissioners of Patents, with
his Petition, on the 1st February 1853.
I, JOSHUA MURGATROYD, of Heaton Norris, in the County of
Lancaster, Millwright and Engineer, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF
BOILERS, AND APPARATUS CONNECTED THEREWITH" to be as follows:
In constructing boilers having the fire-grate within the cylindri-
cal casing, and in other boilers the fire-grates of which are placed
under a projecting end of the boiler, it is very desirable to connect
the roof of the fire-place to the upper part of the casing of the
boiler. In order to effect this, I make plates or stays reaching
from the casing of the boiler to the roof or sides of the fire-place

page_text: and rivetted to both; or I rivet bent or straight plates to the cylin-
drical casing of the boiler, the lower portion of which plates forms
the upper part of the roof of the fire-place, the sides of which are
formed of plates rivetted below to the casing of the boiler, and above
to the plates referred to. In some cases the fire-grate may be
divided into compartments by water spaces formed of tubes, or of
plates rivetted to the casing of the boiler, or to the plate forming
the upper part of the roof of the fire-place, or to both. In order
to add to the strength of boilers, and to supersede the use of
longitudinal stays, I propose to make the ends of the boiler
above the fire-place and the tubes of curved plates; I also pro-
pose in some cases to put my improved boiler together in two or
more parts to facilitate the transporting of the same.
. Another part of my Invention consists in forming a steam chamber
over the smoke box. This chamber is connected by a valve with the
interior of the boiler, and is for the purpose of reheating or drying
the steam before it is taken to the steam engine..
My improvements in apparatus connected with boilers have refe-
rence, in the first place, to certain slides, doors, or dampers placed at
or near the smoke-box end of multi-tubular boilers, with a view to
equalise the distribution of heat in the tubes, and to prevent the
injurious effects of the unequal expansion of the boiler. One mode
of effecting this is by placing two flap doors in the smoke box. These
doors, when closed, cover about three fourths of all the tubes in the
boiler, leaving the lowest tubes uncovered: these lowest tubes can
also be covered by a third door when required. All the doors can be
opened or shut by handles brought to the front of the boiler, so as
to be within reach of the attendant. When both the top doors are
closed, it is evident that the draught from the chimney will cause
the smoke and inflammable gases to pass through the lowest tubes,
thereby clearing them out, and increasing the temperature of the
water near the bottom of the boiler. If the attendant closes the
bottom door, and opens one of the upper doors, it is evident that the
current of smoke and inflammable gases will be greatest through
those tubes that are uncovered, and, by taking care to open the door

page_text: opposite that part of the fire-grate-on-which-fresh. coal. has been
'thrown, the heated air from the incandescent part of the fire will in
a great measure consume the smoke rising from the coal that has
been fresh supplied.
SPECIFICATION in pursuance of the conditions of the Letters
:
Patent, filed by the said Joshua Murgatroyd in the Great
Seal Patent Office on the 29th July 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
JOSHUA MURGATROYD, of Heaton Norris, in the County of Lancaster,
Millwright and Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of February, in the year
of our Lord One thousand eight hundred and fifty-three, in the
sixteenth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Joshua Murgatroyd,
Hér spécial licence that I, the said Joshua Murgatroyd, my
executors, administrators, and assigns, or such others as I, the
said Joshua Murgatroyd, 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 Invention for "IMPROVEMENTS IN THE CONSTRUC-
TION OF BOILERS AND APPARATUS CONNECTED THEREWITH," upon the con-
dition (amongst others) that I, the said Joshua Murgatroyd, by
an instrument in writing under my hand and seal, should particu-
larly 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 Joshua Murgatroyd, do
hereby declare the nature of my said Invention, and in what

page_text: manner the same is to be performed, to be particularly described and
ascertained in and by the following statement (that is to say):
.
My Invention consists, first, in certain improved modes of con
structing and staying the fire boxes and combustion chambers of
boilers, whereby great strength is obtained; secondly, in an im-
proved apparatus for rarefying or drying steam between the boiler
and the steam engine; and lastly, in certain improved apparatus
applicable to boilers, by which heat is more advantageously 'regu
lated in the tubes or flues of the boiler than by the dampers of the
ordinary construction.
And in order that my Invention may be fully understood and
readily carried into effect, I will proceed to describe the annexed
two Sheets of Drawings, reference being had to the letters and
figures marked thereon.
DESCRIPTION OF THE DRAWINGS.
!
On Sheet 1, Figure 1, is a transverse section of a. boiler taken
through the fire box at the line A, B, of Figure 2, which. is a longi-
tudinal section of the same boiler, shewing my improved apparatus
for rarefying the steam and for regulating the draught. Figure 3,
is another transverse section of the boiler taken at the line-C; D,
looking towards the firing end. Figure 4, is an end elevation of the
back of the boiler. Figure 5, is a plan taken in section; and Figure
6, is an elevation of the firing end. a; a, represent the outer casing
of a cylindrical boiler; b, the fire box, the peculiar shape of which
is seen best in Figure 3. The roof of the fire box is formed of a plate
or plates of metal marked 61, of the shape of an inverted arch, the
extremities of which are connected to the shell or outer casing of
the boiler above by angle, tee, or other irons, or by connecting plates
62, reaching from the fire box-roof to the tee iron, or to the shell of
the boiler aforesaid. The stays c, bolted or rivetted to the roof of
the fire box, are also connected to the outer casing by the stay rods
C¹; some of the stays c¹, may be crossed, as shewn by the dotted
lines. d, is the fire-grate; e, the bridge; and f, the tubes, similar to
those in general use. The roof of the fire box near the tube plate

page_text: f, is made flat, as seen in Figure 1, for the purpose of affording
access to the upper row of tubes, or it may be continued in a curve
to the tube plate. It may also be desirable in some cases to make
the plate 6' flat the whole length of the fire box, and stay it by the
stays c, c, and plates 62, which are in some cases perforated, as
shewn in Figures 1 and 3, to afford additional facility for the water
and steam to circulate from the lower to the upper portion of the
boiler. The chamber g, at the end of the boiler in. Figure 2, is in
communication with the interior of the boiler by a valve g¹, and is
for the purpose of rarefying or drying the steam before it enters
the supply pipe, which is not shewn in the drawing, but is affixed
to the chamber in any convenient position. The under side of the
chamber 9, is of a segmental form, as shewn by dotted lines in.
Figures 1 and 4, and the requisite heat for rarefying or drying 'the'
steam in the chamber is obtained from the heated air and other
products of combustion in their passage from the tubes f to the
chimney. In order to give additional strength to the boiler the
front plates over the firing doors may be rounded, as shewn in
dotted lines at a', Figure 2; the back end of the boiler may also be
constructed in the same manner when the chamber g is not re-
quired. The improved apparatus for regulating the draught
through the tubes is seen in one mode of application, in Figures 2,
4, and 5. In these views h, and h¹, are two flap doors, which, when
closed, cover the upper portion of the tubes f; and i, is another door,
which covers the lower tubes when closed. The doors li, and h¹, are
fixed to uprights h², see dotted lines in Figure 4, furnished with levers
h³, to which rods, reaching to the front of the boiler, are hinged.
The door i, is fixed to the shaft i¹, furnished with a lever 2, to
which a rod is attached, also reaching to the front of the boiler. By
this means it is evident that the fire-man can open or close the
doors h, h, and i, without leaving his place at the front of the
boiler. When the doors h and h¹ are both closed, and the door i
open, it is evident that the products of combustion will be drawn
through the lower tubes f, by the draught of the chimney. The
doors h, and , may be closed occasionally in order to increase the

page_text: temperature of the water inthe lower part of the boiler. The com-
bustion of the smoke can also be greatly increased by alternately
opening and closing the doors h, and ', in the following manner:-
When the fire-man puts fresh coal on the righth-hand side of the fire-
grate he must close the door h, which is in a line with it; by so
doing the smoke generated by the fresh coal is conveyed by the
draught in the chimney through the tubes f, in a line with the
open
door ; and as the coals on the left-hand side of the fire d,
are now supposed to be in an incandescent state; it is evident that
the smoke rising from the fresh coals will be ignited and consumed
in passing over or mixing with the heated air rising from the
incandescent portion of the fire. When the coal on the right-hand
side of the grate is properly ignited, and fresh coal is put on the
left-hand side of the grate, the door / is opened, and the door h¹ is
closed, thereby producing in a boiler with a single 'fire-grate a
better effect than the boilers with double firing flues now in use.
In Figures 2 and 3, the dotted lines k, k, represent a series of tubes,
which may sometimes be used to increase the circulation of the
water in the boiler. The tubes k, are connected above to the roof of
the fire-place, and below they are affixed to the horizontal tube l,
one end of which is in communication with the interior of the
boiler, and the other end towards the firing doors is closed. The.
blow-off cock can be affixed to the closed end of the tube ; the
tubes would serve as stays to the roof of the fire box.. When
the tubes are employed, the stays c, and c¹, may be dispensedi
with, or fewer of them used, according to circumstances. In Figure
.7, I have shewn a transverse section of the fire-box of a boiler. The
roof of this fire box is very similar to the one shewn in Figure 3.
The fire-grate, is supposed to reach from one side of the fire-box.to.
the other; and the vertical-pipes m, of which there may be four or
other suitable number, in the length of the grate bars, are placed in
the centre of the fire-grate; the pipes m, are also intended to
increase the circulation of the water in the boiler; they are fur-
nished above with an angle iron ring bolted or rivetted to the top
of the fire-box, into which fits a bridle m¹, through which passes

page_text: When one of
other purpose,
.
the stay rod m², attached above to an angle or tee iron rivetted to
the outer shell of the boiler; or the rod m² may pass through and
have a nut on the outside of the boiler. The under side of the
plate o, which forms an inverted arch, is connected to the outer
shell of the boiler by the stay plates o¹, and by the plates o², which
form the sides of the fire-box. The lower end of the pipe m fits"
on the horizontal pipe n, connected to the end of the fire-box in the
same way as the pipe l, in Figure 2. The pipe n is supported
from the shell of the boiler by the block or blocks n¹.
the tubes m, has to be taken out for repairs or any
the block n', is removed, the fastening at the top of the stay rod m²,
and also those at the top end of the tube m, are taken out; the pipe
n then drops down, and the tube n is thus at liberty to be removed.
Figure 8; represents a transverse section through that part of the
fire-box called the combustion chamber of a boiler, having two
firing flues, shewing the application of my improvements in the.
mode of constructing the roof of the said chamber: I would, how-
ever, remark here that constructing boilers with two firing. flues
and a combustion chamber forms no part of my Invention. In-
this view
P, P, are the corners of the combustion chamber, the lower
portion of which is of the usual form; and p¹, is the roof in the
form of an inverted arch, the plate forming which is stayed from
the outer shell by the side plates p²; or the plate p¹ may be con-
tinued to the outer shell. The plate forming the top of, the
combustion chamber may be made flat and stayed by cross stays;
like c, in Figure 3, and by the side plates p². Figure 9, is a
transverse, and Figure 10, a longitudinal section, through another
of my improved boilers. In these views q, is a chamber under the
grate somewhat similar to the pipe l. In Figure 3, the chamber
is open to the boiler at one end, as shewn in Figure 10, and from it
rise six or other suitable number of pipes q', which pass up the
centre of the fire-grate, and are connected to the roof of the fire-
box and to the outer casing or shell of the boiler. The tubes q',
are perforated with small holes in that part projecting above the
roof of the fire-box, to allow the water rising in them to escape into

page_text: the boiler: by this means a constant current is kept up in the water
to be evaporated. This boiler is furnished with two smoke flues
92, and it is supposed to be set in brick work in the usual manner
as far as the fire box. In order to heat the water with which the
boiler is fed, I place the chamber q³, shewn in dotted lines in Figure
9, at the end of the boiler. The upper part of this chamber consists
of a series of conduits into which the water is forced through the
branch, and out at 95, to the boiler, after it has become heated in
its passage through the conduits. On Sheet 2, Figure 11, is a
transverse section of a boiler, the fire box of which is divided into
two by, the water space r; the plates forming the roofs of the two
compartments of the fire-box are stayed by the curved plate r¹, con-
nected to the outer shell of the boiler, as shewn in the drawing, and
as already described. 2, is a water space under the fire grate, which
is in communication with the water space r. Figure 12, is a
section of a fire-box very similar to the one above described in
Figure 11: in this instance the water space under the fire-grate is
dispensed with, but the division r is retained. Both the above de-
scribed fire-boxes may be used in combination with a multi-tubular
portion of a boiler, or with single or double flues. Figure 13, is a
section of a fire-box provided with a water space all round. The
dotted lines s, indicate upright tubes connecting the lower portion
of the water space with the water above the roof of the fire-box:
These tubes serve as stays to the fire-box, the lower portion of which
is also stayed to the outer shell of the boiler. Figure 14, is
another section of a fire-box, in which there is a water space below
the fire-grate; this water space is marked t, and it is in communica
tion with the other portion of the boiler by holes through the tube
plate, as shewn in Figure 10, on Sheet 1, or by the upright tubes t¹,
indicated by dotted lines. These tubes may also be continued to the
outer shell of the boiler, as shewn by dotted lines, and as described
in reference to Figures 9 and 10. Figure 15, represents a section
of a fire-box furnished with vertical tubes u, and with a large
water space under them. In Figure 16, the fire-box is divided
into two by the water space v, to the upper part of which are

page_text: attached stay plates v₁, reaching in diagonal lines to the outer shell
of the boiler. Figure 17, is a section of a fire-box, also provided
with a row of tubes indicated by dotted lines w. These tubes are
fixed above to the roof of the fire-box; and below to the shell of
the boiler w¹, is a tube placed under the ends of the tubes w. The
plate w², forming the roof of the fire-box, is bent upwards, and con-
nected by plates to the shell of the boiler. Figure 18, represents
a section of a fire-box, the roof of which is formed of the three
plates x, x, x; these plates are either long enough to reach. .up and
be connected to the outer shell of the boiler, or they may be con-
nected to it by connecting plates. The object of making the roof
of the fire-box in three plates is to ensure great strength. Two
plates may in some cases be employed in the same manner, as
shewn in Figure 19. I wish to remark that the above described
improvements are equally applicable to marine and locomotive
engine boilers. Other modifications of this part of Invention
might be given; but the foregoing are sufficient to illustrate my
improved mode of connecting or suspending fire-boxes or other
portions of the boiler from the outer shell thereof..
my
I will now proceed to describe some modifications of my improve-
ments in apparatus for regulating the draught in the tube or flues
of boilers. One arrangement of parts for effecting this object has
already been described in reference to Figures 2, 4, and 5, of Sheet 1.
In Figures 20 and 21, of Sheet 2; I have shewn two flap doors A, A,
which, when closed, leave the lower tubes of the boiler uncovered.
The doors A can be made large enough to cover all the tubes if
required; but it is found desirable to leave the lower ones uncovered,
in order to create a draught through them when the others are
covered. The mode of opening and closing the doors A is
similar to that already described in reference to Figures 2, 4, and 5.
Figure 22, represents the end of a boiler, the tubes or flues of which
are covered, either entirely or partially, by a sliding door B. This
door is suspended by rods and chains passing over suitable pulleys
to the front of the boiler. By this means the fire-man can open or
close the door B, without leaving his place. Figure 23, is another

page_text: end view of a boiler having two sliding doors C, C, for covering the
ends of the tubes or flues. Figure 24, represents an end view of a
boiler, in which the flues or tubes are covered by four flap doors D.
Figure 25, shews how the same object may be effected by two flap
doors E; and Figure 26, represents the mode of applying a single
flap door F.
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 wish it to be under-
stood that I make no claim to any of the well known parts of
the boilers which are shewn in the drawings to illustrate the appli-
cation of my improvements; and I would observe in conclusion that
I do not confine or restrict myself to the precise details or arrange-
ments shewn and described, as many variations may be made
therefrom without departing from the peculiar character of my
Invention. But what I consider to be novel or original, and therefore
claim as the Invention secured to me by the herein-before in part
recited Letters Patent, is, first, the improvements in the construction
of the fire-boxes and combustion chambers of boilers, and in the
mode of connecting the same to the outer casings of boilers, as
herein-before shewn and described in reference to Figures 1 to 19,
or the combination of any two or more of them; secondly, the
improvements in apparatus for rarefying or drying steam, as de-
scribed and shewn in Figures 2 and 4; and, lastly, the improvements
in apparatus for regulating the draught through the flues or tubes
of boilers, as shewn and described in reference to Figures 2, 4, and 5,
and from Figures 20 to 26.
In witness whereof, I, the said Joshua Murgatroyd, have
hereunto set my hand and seal, this Twenty-eighth day
of July, One thousand eight hundred and fifty-three.
JOSHUA MURGATKOYD. (L.S.)