IMPROVEMENTS IN STEAM GENERATORS."
Year: 1881

page_text: LETTERS PATENT to Richard Mills, of Number 3, Victoria Street, in the City
of Westminster, Gentleman, for an Invention of "IMPROVEMENTS IN STEAM
GENERATORS."
PROVISIONAL SPECIFICATION left by the said Richard Mills at the Office
of the Cominissioners of Patents on the 18th October 1881.
RICHARD MILLS, of Number 3, Victoria Street, in the City of Westminster,
Gentleman IMPROVEMENTS IN STEAM GENERATORS."
"
My Invention relates to improvements in steam generators or boilers of the kind
for which Letters Patent, were granted to Thomas Mills and to myself, bearing date
the 14th day of October, A.D. 1876, Number 3979, and consists, firstly, in arranging
the upright tubes of such generators or boilers with a space between each such
tube instead of arranging them close together, as described in the Specification of
the aforesaid Patent, the heat of the furnace being forced to play all round each
tube by the action of the baffle plate or plates placed in the central space enclosed
by the said upright tubes. Secondly, in forming the boxes, pipes, or rings which
connect together the tops and bottoms of the upright tubes (the upper one forming
the space for the collection of steain, and the lower one for the deposit of the mud
or sediment) in two halves bolted together, in such manner that they can be easily
taken apart for the purpose of cleaning; or instead of these connecting boxes, pipes,
or rings being made in halves they may be made each of a single casting provided
with holes and screw plugs opposite the ends of the upright tubes for the purpose
of facilitating the cleansing thereof. Thirdly, in employing in connection with
generators or boilers of the aforesaid description an apparatus, the object of which
is to remove any moisture carried over with the steam, and thus to present priming,
which has hitherto been inseparable from generators or boilers of this class. This
separating apparatus consists of a vessel or chamber of any suitable shape placed
externally to the boiler, and a coil of tube connected therewith but placed inside
the space enclosed by the main tubes of the generator or boiler and above the

page_text: baffle plate or plates, and subjected to the heating effect of the products of com-
bustion as they escape to the chimney. The steain generated in the main tubes of
the boiler is conducted by preference, firstly, to the aforesaid vessel placed externally
to the boiler, and afterwards through the aforesaid coil of tube to the engine. The
steam on entering the said vessel or chamber is caused to pass under a partition
before emerging therefrom, or the current of steam is otherwise broken therein
before passing to the coil.
Part of the moisture in the steam is reinoved therefrom in the said external
vessel or chamber and is deposited at the bottom thereof, whence it may be with-
drawn when necessary by means of a cock provided for that purpose. The moisture
remaining in the steam after it has passed through the external vessel or chamber
is evaporated in the internal coil, and the volume of steam is materially increased
by this additional evaporation, and by the superheating to which the whole is
subjected.
In some cases the steam from the boiler may be caused to pass through the coil
first, and then through the aforesaid vessel or chamber.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Richard Mills in the Great Seal Patent Office on the 18th April
1882.
RICHARD MILLS, of 3, Victoria Street, in the City of Westminster, Gentleman.
"IMPROVEMENTS IN STEAM GENERATORS."
My Invention relates to improvements in steam generators or boilers of the kind
for which Letters Patent were granted to Thomas Mills and to myself, bearing date
the 14th day of October, A.D. 1876, Number 3979, and consists,―
Firstly. In arranging the upright tubes of such generators or boilers with a
space between each such tube instead of arranging them close together, as described
in the Specification of the aforesaid Patent, the heat of the furnace being forced to
play all round each tube by the action of the baffle plate or plates placed in the
central space enclosed by the said upright tubes.
Secondly. In forming the boxes, pipes, or rings which connect together the tops
and bottoms of the upright tubes (the upper one forming the space for the collection
of steam, and the lower one for the deposit of the mud or sediment) in two halves
bolted together in such munner that they can be easily taken apart for the purpose
of cleaning; or instead of these connecting boxes, pipes, or rings being made in
halves, they may be made each of a single casting provided with holes and screw
plugs opposite the ends of the upright tubes for the purpose of facilitating the
cleansing thereof.
Thirdly. In employing in connection with generators or boilers of the aforesaid
description an apparatus, the object of which is to remove any moisture carried
over with the steam, and thus to prevent priming, which has hitherto been
inseparable from generators or boilers of this class. This separating apparatus
consists of a vessel or chamber of any suitable shape placed externally to the boiler,
and of a coil of tube connected therewith, but placed inside the space enclosed by
the main tubes of the generator or boiler and above the baffle plate or plates, and
subjected to the heating effect of the products of combustion as they escape to the
chimney. The steam generated in the main tubes of the boiler is conducted by
preference, firstly, to the aforesaid vessel placed externally to the boiler, and after-
wards through the aforesaid coil of tube to the engine. The steam on entering the
said vessel or chamber is caused to pass under or over a partition before emerging
therefrom, or the current of steam is otherwise broken therein before passing to
the coil.
Part of the moisture in the steam is removed therefrom in the said external
vessel or chamber and is deposited at the bottom thereof, whence it may be with-
drawn when necessary by means of a cock provided for that purpose; the moisture
remaining in the steam after it has passed through the external vessel or chamber
is evaporated in the internal coil, and the volume of steam is materially increased
by this additional evaporation, and by the superheating to which the whole is
subjected.
And in order that the said Invention may be clearly understood, I will now
proceed to describe the annexed Drawings in which the above described improve-
inents are illustrated.
Figure 1 is a vertical section of a generator or boiler of this construction with
the said various improvements applied thereto; and Figure 2 is a sectional plan of
same taken on line 1-2 of Figure 1.

page_text: A, A, are the upright tubes forming the principal parts of the generator or
boiler, each of these tubes being provided with a U shaped circulating tube B as
well understood. These upright tubes are placed, as shown in the plan, Figure 2,
with spaces between them instead of being close together as heretofore practised,
whereby the heat of the furnace is forced to play all round each tube by the action
of the baffle plate C which is extended for that purpose nearly to the said upright
tubes.
D is an iron or other suitable casing surrounding the tubes A, A, and serving to
enclose the fire; this casing is preferably covered with a suitable non-conducting
coating D' to prevent radiation of heat. E is the up-take; F, the fire-grate.
G is the upper box, pipe, or ring connecting together the tops of the upright
tubes A, A, and forming the collecting space for the steam generated. G' is the
lower box, pipe, or ring connecting together the bottoms of the upright tubes A, A,
and forming the depositing space for the mud or sediment. These boxes, pipes, or
rings are each formed in two halves jointed together by flanged joints, as shown,
so that when it is required to clean out or examine the upright tubes A, A, it is
only necessary to remove the upper or lower half of one or other or both of the said
boxes, pipes, or rings in order to obtain access to such tubes A, A. Figure 3 shows
another arrangement of these boxes, pipes, or rings, in which they are each made
of a single casting provided with holes and screw plugs H opposite the ends of the
tubes A, A, whereby access can be obtained to any one or all of the latter when
necessary; Figure 4 shows another modification in which the boxes or rings G, G',
are fitted with cover plates I secured by bolts and nuts passing through the
flanges.
J is the separating vessel or chamber placed externally to the boiler and
preferably covered with non-conducting composition J' to prevent radiation of
heat. K is a coil of tube connected at one end by the tube L with the vessel or
chamber J, the other end being connected by the tube M with the steam engine or
other point at which the steam is to be supplied. The coil K is placed in the
space enclosed by the main tubes A, A, and above the baffle plate C. The steam is
conducted from the steam space over the upright pipes A, A, by a pipe N extending
more or less towards the bottom of the vessel or chamber J, the outlet to the tube L
being at the top of such vessel or chamber; or instead of the pipe N the said vessel or
chamber J inay be furnished with a partition, and the steain being admitted into
the vessel or chamber at or.e side of the partition is caused to pass under or over
the same before escaping from the vessel or chamber at the other side of the
partition.
Whichever method be adopted the greater portion of the moisture in the steam
is deposited in the vessel or chamber J, whence it may be withdrawn when
necessary by a cock, steam trap, or other suitable device.
The remaining moisture in the steam is afterwards evaporated in the coil K, so
that dry steam is delivered to the engine or other point where it is to be used.
Similar letters refer to like parts in each of the Figures of the Drawings.
Having now described the nature of the said Invention, and the manner in
which the same is to or may be carried into effect, I would have it understood
that I make no claim to the general construction of boilers or generators of the
kind described as they are now well known, but what I do claim as the improve-
ments to be secured by the within in part recited Letters Patent is,-
First. The construction of generators or boilers of the kind herein before
mentioned, with the vertical tubes A, A, separated from one another sufficiently
to allow the flame and heated products of combustion to play round the same, the
said tubes so placed being combined with the baffle plate C, as hereinbefore described
and illustrated in Figure 2 of the Drawings.
Second. The construction of the boxes, pipes, or rings G, G¹, connecting together
the upper or lower ends of the tubes A, A, either in two halves, as shown in
Figure 1, in one piece, with holes and plugs, as shown in Figure 3, or in one piece

page_text: with a cover plate, as shown in Figure 4, as hereinbefore described and for the
purposes set forth.
Third. The employment in combination with generators or boilers of the kind
hereinbefore mentioned of the external separating vessel or chamber J and the
internal coil K, as hereinbefore described and illustrated in Figures 1 and 2 of the
Drawings, and for the purposes specified.
Fourth. In generators or boilers of the kind hereinbefore mentioned, the combi-
nation of the vertical tubes A, A, separated from one another, as herein specified,
the baffle plate C, the connecting boxes, pipes, or rings, G, G¹, constructed in one
or other of the manners specified, the separating vessel or chamber J and the
coil K, as hereinbefore described and illustrated in the Drawings.
In witness whereof, I, the said Richard Mills, have hereunto set my hand
and seal, this Seventeenth day of April, in the year of our Lord One
thousand eight hundred and eighty two.
RICHARD MILLS. (L.S.)