IMPROVEMENTS IN FUEL ECONOMISERS ADAPTED TO BE EMPLOYED IN THE HEATING OF FEED WATER FOR STEAM GENERATORS
Year: 1873

page_text: LETTERS PATENT to Thomas Arthur Nield, of Dukinfield, in the
County of Chester, Engineer, for the Invention of "IMPROVEMENTS IN
FUEL ECONOMISERS ADAPTED TO BE EMPLOYED IN THE HEATING OF FEED WATER
FOR STEAM GENERATORS,”
Sealed the 6th June 1873, and dated the 26th March 1873.
PROVISIONAL SPECIFICATION left by the said Thomas Arthur Nield
at the Office of the Commissioners of Patents, with his Petition,
on the 26th March 1873.
I, THOMAS ARTHUR NIELD, of Dukinfield, in the County of Chester,
Engineer, do hereby declare the nature of the said Invention for "Im-
PROVEMENTS IN FUEL ECONOMISERS ADAPTED TO BE EMPLOYED IN THE HEATING OF
FEED WATER FOR STEAM GENERATORS," to be as follows:-
My Invention relates to the apparatus now well-known as fuel
economisers, and usually employed to effect the heating of the water
with which steam generators are fed or supplied. In such apparatus
the feed water is caused to circulate through a series of pipes which are
outwardly exposed to the heated gases flowing towards the chimney.

page_text: In a form of economiser which has been employed previously to my
said Invention the said pipes have been made in a spiral form, and the
action of the water when forced through the said pipes has had a
tendency to cause a vibration in the coils of the spirals, and the security
of the joints and the durability of the apparatus has thereby been
affected.
In my said Invention I employ pipes of an annular form. Each pipe
is cast or formed with branches, by means of which any suitable number
of the said pipes or rings may be connected together so as to form a
stack or combination of rings, the water being caused to flow from one
ring to another throughout the series, and being conducted to another
stack or series if there be more than one series in the complete
apparatus. Each ring is fitted with a scraper or with two or more
scrapers which are caused to revolve around the common central axis of
the rings in a series, and I prefer to so form and arrange the said
scrapers as that they or a part or parts of each scraper or of each set of
scrapers shall yield or be moved out of the way when approaching each
of the branches cast or formed on each ring, as aforesaid, in order that
the whole or nearly the whole of the outer surface of the ring betwcon
the said branches may be scraped.
In an arrangement which I consider to be suitable the scraper which
acts upon the portion of the surface upon which the said branches are
cast or formed is hinged, and is held in contact with the ring by means
of a weight. An incline formed on the ring at or near each branch acts
upon the hinged scraper for the purpose aforesaid.
If the apparatus is to be used in the superheating of steam the said
steam must be caused to flow through the rings instead of water.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Arthur Nield in the Great Seal Patent
⚫ Office on the 26th September 1873.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-sixth day of March, in the year
of our Lord One thousand eight hundred and seventy-three, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Thomas Arthur Nield, Her special
license that I, the said Thomas Arthur Nield, executors, adminis-
trators, and assigns, or such others as I, the said Thomas Arthur Nield,
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 FUEL ECONOMISERS ADAPTED TO BE EMPLOYED IN THE HEATING
OF FEED WATER FOR STEAM GENERATORS," upon the condition (amongst
others) that I, the said Thomas Arthur Nield, 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 Thomas Arthur Nield, 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 statement, and accompanying Drawings, that is to
say:―
My Invention relates to the apparatus now well-known as fuel
economisers, and usually employed to effect the heating of the water
with which steam generators are fed or supplied. In such apparatus the
feed water is caused to circulate through a series of pipes which are
outwardly exposed to the heated gases flowing towards the chimney.
.
In a form of economiser which has been employed previously to my
said Invention the said pipes have been made in a spiral form, and the
action of the water when forced through the said pipes has had a
tendency to cause a vibration in the coils of the spirals, and the security
of the joints and the durability of the apparatus has thereby been
affected.
In my said Invention I'employ pipes of an annular form. Each pipe
is cast or formed with a branch or with hwanches by moons of whil

page_text: any suitable number of the said pipes or rings may be connected together
so as to form a stack or combination of rings, the water being caused to
flow from one ring to another throughout the series, and being conducted
to another stack or series if there be more than one series in the complete
apparatus. Each ring is fitted with a scraper, or with two or more
scrapers, which are caused to revolve around the common central axis of
the rings in a series, and I prefer to so form and arrange the said
scrapers as that they or a part or parts of each scraper or of each set of
scrapers shall yield or be moved out of the way when approaching the
branch or branches cast or formed on each ring as aforesaid, in order
that the whole or nearly the whole of the outer surface of the ring
between the said branches may be scraped.
And in order that my said Invention may be fully understood I will
now refer to the accompanying Sheet of Drawings, illustrative of the
manner in which I prefer to carry the said Invention into practical effect,
the said Drawings being marked with letters of reference, corresponding
marks indicating the same parts in the various Figures.
In the said Drawings Fig. 1, drawn to a scale of about one inch to the
foot, represents a vertical section, and Fig. 2 a horizontal section of two
stacks of rings connected together, A, A, being the line of section of
Fig. 1. In the said Figures B, B, are cast-iron rings, each of which is
formed with a double branch a, by means of which it is attached to the
central connecting pipe C, the opening in the said branch being divided
by the mid-feather 6 into an inlet and an outlet passage for the flow of
water into and from the ring. The pipe C is formed on each side with
faces, as seen at c, c, in Fig. 3, which is taken at right angles to Fig. 1
on the vertical plane D, D. An inlet and an outlet passage are also
formed in each of the said faces, and the said faces and the faces of the
branches a are or may be planed or faced, and means are provided for
bolting or securing together the faces on the said branches and on the
said pipe. The said pipe is formed with a vertical mid-feather d, and
with horizontal curved partitions, the said mid-feather and partitions
dividing the interior of the pipe into a number of separate passages,
which regulate the flow of water. Each stack of pipes is provided with
a central vertical shaft e, which is fitted to revolve in a footstep ƒ and a
bearing g, and is provided with a worm wheel h, with which gears a
worm fixed on the shaft i, which is caused to revolve by means of the
strap pulley j, or by other suitable means. In the example illustrated there

page_text: would be more than two stacks of rings in the complete economiser,
and therefore there are two shafts i, i, each shaft giving motion to two
or more of the vertical shafts e. In an economiser having only two
stacks of rings one horizontal worm shaft would actuate both of the said
vertical shafts. A frame, consisting of an upper and a lower cross-
picce k, k, and of vertical rods m, m, is fixed on each of the shafts i, i,
and carries round the scraper carriers n, n, two only of which are shown
in position in cach stack, it being understood that there is one such
carrier to each ring. The said carrier is represented on a larger scale in
plan in Fig. 4, and in side elevation in Fig. 5. At one end of the said
carrier a semicircular scraper o is mounted on two studs, and is retained
thereon by means of cottars, or it may be by means of bolts and nuts or
other suitable appliances. The said scraper is or may be formed with a
V shaped scraping edge, and there is a suitable amount of lateral play in
the slots, through which the said studs pass, in order that the scraper
when in action may be able to accomodate itself more readily to
variations in the form of the rings. To each carrier is jointed a lever p,
on which is mounted a scraper q in the same manner as the scraper o,
the said lever being formed with a balance weight, which tends to press
the scraper q against the lower half of the ring. When each carrier is
in position the scraper o and the opposite end of the scraper carrier rest
upon the upper part of the ring, and the lower scraper is pressed
upwards against the lower part of the ring, and as all the scrapers in each
stack are carried round by the action of the revolving shaft e and the
frame k, m, the whole or the greater part of the outer surface of each
ring is scraped. As the scraper 7 approaches the branch a an incline or
cam surface, shewn in Fig. 6, acts on the nose of the said scraper, which
is formed with double inclines, as seen in the said Figure, and forces it
downwards, as seen in Fig. 1, the lever p yielding until the scraper has
passed or nearly passed the branch, when the said scraper is permitted
to rise again and to act upon the ring. The water to be heated enters
at r, and flows in the direction indicated by the arrows through the
lowest ring in the stack, which is to the left hand in Figs. 1 and 2, and
leaving the said ring flows through a passage in the pipe C into the
lowest ring in the right hand stack, and after flowing through the said
ring in the direction indicated is conducted to the next higher ring in
the left hand stack. The water is thus caused to flow successively
through all the rings in the two stacks, and is then conducted by the
branch pipes to the pipe which connects the next two stacks of rings.

page_text: The outer surfaces of the rings being exposed to heated gases in a flue or
chamber, as is usual, the water becomes heated in its passage.
The direction in which the water flows through the apparatus, and the
arrangement of the connecting passages, may be varied so long as the
water is caused to flow through rings which are outwardly scraped, as
for example, cach ring may be connected with two upright pipes, as
shewn in Fig. 7; the water flowing from one pipe through all the rings
to the other pipe, or flowing successively through all the rings, as may
be preferred. In some cases a single stack of rings may be connected
by one upright pipe, as shewn in Fig. 8, in which the said pipe is
represented in section, in order to display the arrangement of the
passages for regulating the flow of the water, the complete economiser
consisting of only one stack of rings, or of two or more stacks, as may be.
required. The direction of motion of the shaft e may be reversed at the
times when the scrapers approach the branches a, in which case the said
scrapers would not pass the said branches, but I prefer the arrangement
herein-before described.
In the example illustrated in Fig. 1 the rings are supported solely by
the central upright pipe C, with the exception of the two lowest rings,
which are partly supported by brackets u, u. If preferred or considered 2
to be desirable all the rings in each stack may be "steadied" or partly
sustained by means of brackets, or in the case of the said lowest rings,
the lower scrapers being depressed when passing such brackets, as when
passing the branches a, a.
Although the improved economiser is adapted more particularly to be 2
used in the heating of feed water for steam generators, it may be used in
the heating of other liquids, if required, or in the superheating of steam,
in which latter case the steam to be superheated would be caused to flow
through the rings in place of water.
Having now fully described the nature of my said Invention, I would 8
in conclusion have it to be distinctly understood that I claim as secured
to me by the herein-before mentioned Letters Patent,-
First. The employment of hollow rings in fuel economisers, substan-
tially in the manner herein-before set forth and indicated.
Secondly. The scrapers and the parts in connection therewith, arranged 3
and acting substantially as herein-before set forth and indicated.

page_text: And lastly. The general arrangement and combination of parts forming
a complete apparatus for heating fluids, substantially as described and
indicated herein-before and in the accompanying Drawings.
In witness whereof, I, the said Thomas Arthur Nield, have here-
unto set my hand and seal, this Twenty-fourth day of September,
in the year of our Lord One thousand eight hundred and seventy-
three.
Signed and sealed by the said
Thomas Arthur Nield, in
the presence of
EDWARD K. DUTTON,
"
THOMAS ARTHUR NIELD. (L.S.)
Agent for the Patentee,
3, Princess Street,
Manchester.