IMPROVED METHOD OF AND MEANS OR APPARATUS FOR PREVENTING OR COUNTERACTING INCRUSTATION IN AND DETACHING IT FROM STEAM BOILERS
Year: 1873

page_text: LETTERS PATENT to Edward Field, of Chandos Chambers, Adelphi,
in the City of Westminster, Consulting Engineer, for the Invention
of "IMPROVED METHOD OF AND MEANS OR APPARATUS FOR PREVENTING OR
COUNTERACTING INCRUSTATION IN AND DETACHING IT FROM STEAM BOILERS
Scaled the 20th December 1873, and dated the 28th June 1873.
PROVISIONAL SPECIFICATION left by the said Edward Field at the
Office of the Commissioners of Patents, with his Petition, on the
28th June 1873. ..
I, EDWARD FIELD, of Chandos Chambers, Adelphi, in the City of
Westminster, Consulting Engineer, do hereby declare the nature of the
said Invention for "IMPROVED METHOD OF AND MEANS OR APPARATUS FOR
PREVENTING OR COUNTERACTING INCRUSTATION IN AND DETACHING IT FROM STEAM
BOILERS OR APPARATUS ICR IMPARTING HEAT TO LIQUIDS," to be as follows:-
.
My Invention is designed to prevent or counteract incrustation in
steam boilers or heating apparatus, and to enable scale already formed
therein to be detached therefrom by simple and practicable means; the
i

page_text: efficient operation of which shall not be liable to interruption by the
action of foreign matters contained in the water to be heated or evapo-
rated.
The first part of my Invention consists in preventing or counter-
acting incrustration by the use or employment within the boiler or
heating. vessel of a piece or pieces of metal electro-negative to the
metal of the boiler or heating vessel, such electro-negative metal
being submerged or immersed in the water or liquid within the
boiler or heating vessel, and connected to the metal forming the shell
or body of the boiler or heating vessel by a suitable conducting wire
or connexion or connexions in such manner as to establish and maintain
a voltaic current or currents from the shell or body of the boiler towards
the submerged or immersed piece or pieces of electro-negative metal,
a clean surface being maintained upon the said piece or pieces of electro-
negative metal by the use, in conjunction therewith, of a loose or
moveable piece (or pieces), or terminal (or terminals), or cleaning
device actuated by the motion of the water or liquid, or by other
means, in such manner as to cause a part or parts of the said moveable
piece (or pieces), or terminal (or terminals), or cleaning device to work
upon or rub against a part or parts of the said piece or pieces of electro-
negative metal below the water line, in order to keep such part or parts
of the said piece or pieces of clectro-negative metal clean and free from
deposit.
It will be evident that various forms and arrangements of cleaning
devices may be used in conjunction with the piece or pieces of electro-
negative metal for the purposes of my Invention.
Another part of my Invention has reference to the method of pre-
venting or counteracting incrustation in steam boilers or apparatus
for imparting heat to liquids, described in the Specification of Letters
Patent, granted to me the 1st day of April, 1871 (No. 870), which
method relates to connecting the positive electrode of a battery with
the shell or body of the boiler or heating apparatus, and passing the
negative electrode through the said shell or body, but insulated there-
from, and causing such negative electrode to protrude into the water
or liquid contained in the boiler or heating apparatus..
Now according to my present Invention in order to maintain a clean
surface on the submerged part of the aforesaid negative electrode, and

page_text: to prevent deposit thereon, which might prevent its proper action, I
connect or combine with the said negative electrode a loose or moveable
picce (or picces), or terminal (or terminals), or cleaning device of any
suitable construction actuated by the motion of the water, or by other
means, in such manner as to cause a part or parts of the moveable
picce (or pieces), or terminal (or terminals), or cleaning device to work
upon or rub against a part or parts of the said negative electrode below
the water line, so as to keep such part clean and free from deposit.
This method of preventing or counteracting incrustation may, by the
use of more powerful currents, be advantageously adapted for detaching
or removing scale already formed on the interiors of boilers or heating
apparatus.
My Invention furthermore relates to the use or. employment in
apparatus for preventing, counteracting, or removing incrustration, as
described, of a galvanometer for indicating the strength of the current
or currents of electricity passing through the circuit.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Field in the Great Seal Patent Office
on the 27th December 1873.
.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
FIELD, of Chandos Chambers, Adelphi, in the City of Westminster,
Consulting Engineer, send greeting.
'
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-eighth day of June, in the year
of our Lord One thousand cight hundred and seventy-three, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Edward Field, Her special licenso
that I, the said Edward Field, my executors, administrators, and assigns,
or such others as I, the said Edward Field, 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 "IMPROVED METHOD OF AND MEANS OR

page_text: APPARATUS FOR PREVENTING OR COUNTERACTING INCRUSTATION IN AND DETACHING
IT FROM STEAM BOILERS OR APPARatus for ImpartiNG HEAT TO LIQUIDS,” upon
the condition (amongst others) that I, the said Edward Field, my
executors or administrators, by an instrument in writing under my,
or their, or one of their hands and seals, 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Edward Field, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof and the Drawings therein referred to (that
is to say):
--
My Invention is designed to prevent or counteract incrustation in
steam boilers or heating apparatus, and to enable scale already formed
therein to be detached therefrom by simple and practicable means, the
cfficient operation of which shall not bel iable to interruption by the action
of foreign matters contained in the water to be heated or evaporated.
The first part of my Invention consists in preventing or counteracting
incrustation by the use or employment within the boiler or heating
vessel of a piece or pieces of metal electro-negative to the metal of
the boiler or heating vessel, such electro-negative metal being sub-
merged or immersed in the water or liquid within the boiler or heating
vessel, and connected to the metal forming the shell or body of the
boiler or heating vessel by a suitable conducting wire or connexion or
connexions in such manner as to establish and maintain a voltaic
current or currents from the shell or body of the boiler towards the
submerged or immersed piece or pieces of electro-negative metal, a
clean surface being maintained upon the said piece or pieces of electro-
negative metal by the use in conjunction therewith of a loose or
moveable piece (or pieces), or terminal (or terminals), or cleaning
device, actuated by the motion of the water or liquid, or by other
means, in such manner as to cause a part or parts of the said moveable
piece (or pieces), or terminal (or terminals), or cleaning device, to work
upon or rub against a part or parts of the said piece or pieces of electro-
negative metal below the water line in order to keep such part or parts

page_text: of the said piece of pieces o
deposit.
VILL
It will be evident that various forms and arrangements of cleaning
devices may be used in conjunction with the piece or pieces of electro-
negative metal for the purposes
of my
Invention.
Another part of my Invention has reference to the method of
preventing or counteracting incrustation in steam boilers or apparatus
for imparting heat to liquids, described in the Specification of Letters
Patent granted to me the First day of April 1871 (No. 870), which
method relates to connecting the positive electrode of a battery with
the shell or body of the boiler or beating apparatus, and passing the
negative electrode through the said shell or body, but insulated there-
from, and causing such negative electrode to protrude into the water
or liquid contained in the boiler or heating apparatus.
Now according to my present Invention in order to maintain a clean
surface on the submerged part of the aforesaid negative electrode, and
to prevent deposit thereon, which might prevent its proper action, I
connect or combine with the said negative electrode a loose or movcable
piece (or pieces), or terminal (or terminals), or cleaning device of any
suitable construction, actuated by the motion of the water or by other
means in such manner as to cause a part or parts of the moveable
picce (or picces), or terminal (or terminals), or cleaning device, to
work upon or rub against a part or parts of the said negative clectrode
below the water line, so as to keep such part clean and free from
deposit. This method of preventing or counteracting incrustation may
by the use of more powerful currents be advantageously adapted for
detaching or removing scale already formed on the interiors of boilers
or heating apparatus.
My Invention furthermore relates to the use or employment in
apparatus for preventing, counteracting, or removing incrustation, as
described, of a galvanometer, for indicating the strength of the current
or currents of clectricity passing through the circuit.
Figs. 1, 2, and 3 (Sheet 1) of the Drawings shew the application of
the first part of my Invention to an ordinary Cornish boiler.
Within the iron boiler a is a piece of copper 6 formed somewhat
like a roof, in transverse section, with its upper surface corrugated or

page_text: grooved; this piece of copper is submerged or immersed in the water
within the boiler, where it is held by a wrought-iron frame c attached
to and held by a wrought-iron suspending rod d, which passes up
through an insulating arrangement so arranged as to insulate that
part of the suspending rod from the shell of the boiler. For this
purpose, and in order also to establish the necessary metallic connection
between the submerged piece of copper b and the iron shell of the
boiler a through the iron suspending rod d, and other parts, as herein-
after mentioned, a cast-iron body piece e is connected metallically
to the shell of the boiler by a screwed wrought-iron pipe piece f, which
to ensure perfect metallic contact is screwed without cement into the
cast-iron body piece e, as well as into the shell of the boiler a. The
cast-iron body piece e is provided with a cast-iron tightening flange
or cover g, and contains an earthenware insulator formed with a hole
through which the suspending rod d passes up through the shell of the
boiler.
Another similar insulator is placed above the insulator already
mentioned, and between these two insulators an india-rubber ring or
washer is interposed to make a tight joint and prevent any escape of
steam from the boiler. The two carthenware insulators and the india-
rubber ring or washer are held down by tightening bolts passing
through the flange or cover g, and through the flange of the body
piece e as shewn. d' is a brass or gun metal screw clip screwed on to
the upper end of the suspending rod d, and embracing it in such manner
as by resting upon the upper insulator as shewn to prevent the falling
of the rod. This metal screw clip serves also to connect the rod d by a
copper wire d through a galvanometer d³, a copper wire d', and the
body picco to the shell of the boiler a, the copper wire d* being
attached to the body piece e by a holding screw or clip d³.
Above the piece of copper 6 and resting upon its corrugated surface is
another piece of copper k, similarly formed excepting that it is open at
the ridge and is grooved or corrugated on its under surface instead of on
its upper face, which latter is provided with a projecting peice ¹ slotted
as shewn to receive freely the end of a tongue lever having its fulcrum
in the iron shaft / carried by bearings in the frame c bushed with gun
metal. On one end of the shaft is fixed one end of an iron arm ľ²
whose other end has attached to it an inverted iron scoop-shaped
vessel m, so constructed that steam generated in the boiler may

page_text: accumulate within such scoop-shaped vessel, and by displacing water
therefrom may render the vessel sufficiently buoyant to raise it, say into
the position indicated by dotted lines at m² (Fig. 2), so that steam will
escape from within the scoop-shaped vessel which being made sufficiently
heavy will thereupon fall to a lower level as indicated by the dotted
lines at me. This frequent rising and falling of the scoop-shaped vessel
will communicate through the arm, shaft 1, and tongue lever 1, a
reciprocating or to-and-fro movement to the piece of copper k, whose
corrugated surface will be thereby caused to work upon or rub against
the corrugated surface of the piece of copper b, thereby keeping
such last-mentioned surface clean and free or comparatively free from
deposit or incrustation, and in proper condition for inducing the
requisite currents of electricity from the shell of the boiler through the
water towards the said piece of copper b and thence through the frame c,
rod d, wire d, galvanometer d³, wire d'; and body picce e, back to the
shell of the boiler a, and so on.
The object of the galvanometer is to ascertain what is known as the
direction of the clectric current. Whilst the galvanometer is being
fixed it should be disconnected from the boiler, care being taken that
the needle swings freely and comes to rest over the north point. I find
when the one terminal of the galvanometer coil is connected with the
shell of the boiler, and the other terminal is connected with the water of
the boiler through the insulator by the iron rod d, as shewn in the
Drawings, but without the copper plate b, that upon steam being.got up
in the boiler there is a strong deflection of the needle towards cither the
cast or the west according to the arrangement of the coil of the
galvanometer, and that while this current (which I have found to exist
in all the boilers I have tested) is passing, incrustation of carthy matter
takes place on the metal of the boiler. By immersing the piece of
copper b with its cleaning device in the water of the boiler, and with the
copper plate 6 in electrical connection with the rod das herein-before
described, the current will be reversed and the needle of the galvanometer
deflected in the contrary direction. I also find that when the needle is
deflected in this last-mentioned direction to from 15 to 20 degrees or
thereabout no scale is formed on the metal of the boiler.
It may in some cases be found convenient to dispense with the scoop-
shaped vessel m, arm &², shaft 1, and tongue lever 7; and to communicate
the necessary movement to the piece of copper k from an external source,

page_text: imparting neat to fiquids.
Fig. 6 (Sheet 2) is a general view shewing the application to an
ordinary Cornish boiler of that part of my Invention which relates to
the use for preventing or counteracting incrustation, and detaching it
when formed of a battery in conjunction with means for keeping a part
of the submerged electrode of such battery clean and free from deposit
or incrustation.
Fig. 7 is a plan of the insulating arrangement.
Figs. 8 shew the description of battery I prefer to use for stationary
boilers. The battery is a constant gravitating battery; its earthenware
jar q is formed with internal lugs q¹, and provided with a cover q³, in
which are circular apertures 9%, q'. is a circular copper plate, whose
periphery is notched and bent down about one-quarter of an inch to
keep the plate off the bottom of the jar. A copper wire is attached
to and rises from the centre of this copper plate r. 8 is a zinc plato
which rests upon the lugs q¹ of the jar q, and has a circular aperture in
its centre for a glass tube t to pass through. This zinc plate s also has
attached to it a copper wire s¹, which rises vertically from the edge of
the centre aperture in the plate, and passes up on the outer side of the
glass tubet through a notch q³ in the cover q³. The glass tube t is open
at its top and has a contracted aperture at the bottom. The jar q is put
into a wooden box or case u with the wire s¹ to the left hand.
The box or case with the battery and the galvanometer herein-after
mentioned are placed and securely fixed on a shelf before the battery is
charged. The glass tube t having been slipped over the wire and
passed down through the cover q² and through the zinc plates is then
filled with crystals of sulphate of copper, and the jar q is filled up with
warm water poured in through the aperture 7', which being then corked
up the battery is ready for work. The front side u¹ of the wooden case
is hinged at its lower edge so as to open downwards into a horizontal
position, and on its inner side it has secured to it by suitable clips u² a
galvanometer d³, whose needle works freely and comes to rest on the
north point. To the piece u³ running across the top of the front of the
box or case u are attached two binding screws v, v¹. The binding screw v
is in direct connection with the wire s' attached to the zinc plates of
the battery. The other binding screw v₁ is connected by a wire v² with

page_text: one end of the coil of the galvanometer. The other end of this coil is
connected with a small V piece vs. 4 is a spring contact breaker, which
in its normal position bears against the V piece v³, contact being broken
when the free end of the breaker is raised. The other end of the breaker
is connected by flexible wire to the wire attached to the copper
plate of the battery. The binding screw is connected by a copper
wires with the copper rod s³, whose lower end dips or protrudes into
the water in the boiler a and forms the negative electrode of the battery.
This negative electrode passes through the shell or body of the boiler a
without metallic contact therewith.
In order to keep a submerged part (or parts) of this electrode
perfectly clean, and to prevent. the formation upon it of deposit or
incrustation calculated to prevent or retard its efficient action, I connect
with it a loose or moveable piece, terminal, or cleaning device k, which
may consist of a small inverted copper cup or bell jointed loosely to the
electrode s³, so as to be capable of swinging freely in any direction, as
shewn in Fig. 6, without coming into metallic contact with any part of
the boiler a, such cup being mainly actuated by the rising steam dis-
placing water from within it; or the lower portion of the electrode s³
may be made of a fork shape, each prong of its forked end being sub-
merged or immersed, and each provided with a small inverted cup or
bell, as shewn in Fig. 9; or the electrode made in the form of a
straight rod may be provided with a cleaning device, consisting of a
copper float k (Fig. 10) made water-tight, and having a copper tube k¹
through its centre, such copper tube passing freely around the clec-
trodes, so that as the ebullition of the water causes the float to rise
and fall it shall work upon or rub against a part or parts of the elec
trode s³ below the water line; but I do not confine myself to the precise
shapes or arrangements of cleaning devices shewn, so long as the elec-
trode &³ is provided with a loose or moveable piece or pieces, or terminal
or terminals, or cleaning device for keeping a part or parts of such
electrode clean and free from deposit or incrustation, as aforesaid. The
cast-iron body piece e is in metallic connection with the boiler a through
the wrought-iron tube piece f; w, w¹, are carthenware insulators having
an india-rubber washer / between them, and held in position by the cap
or cover and bolts i. The shell of the boiler a is connected through
the body picce e, wire 5, binding screw v¹, wire v², galvanometer d³,
V piece vs, breaker v', wire r², and wire r¹ with the copper plate r of the
battery. The binding screw d¹ prevents the falling of the clectrode s³.

page_text: · The red arrows in Fig. 6 shew what is known as the direction of the
electric current as indicated by the galvanometer when the apparatus
is connected with the boiler, and properly in action.
I prefer arranging the coil of the galvanometer and attaching the
wires thereto in such manner that the "battery current" shall deflect
the needle towards the cast point, and so that what I call the "boiler
current," that is, a current I have observed from the water, to the shell
in boilers when steam is up, and which current it is the object of my
Invention to counteract or reverse in order to prevent the formation of
scale on the surface of the boiler, shall deflect the needle towards the
west.
In Fig. 6 the parts are shewn to a scale of about three inches to a
foot. I have found batteries of the kind above described and illustrated
when fed occasionally with crystals of sulphate of copper to give a
steady constant current of the required strength for from twelve to
eighteen months without renewal of the zinc plate. I prefer to use
insulated wires for conveying the electric current from the battery to
the boiler.
Although I have described the battery which I consider to be the best
for stationary purposes I do not confine myself to the precise arrange-
ment of battery shewn.
Having described my said Invention of " Improved Method of and
Means or Apparatus for Preventing or Counteracting Incrustation in
and Detaching it from Steam Boilers or Apparatus for Imparting Heat
to Liquids," and having explained the manner of carrying the same into
practical effect, I hereby declare that I do not claim as of my Invention
or the exclusive use of the several parts hercin-before described and
referred to, except when the same are used in and for the purposes of
my said Invention; but what I do claim is,-
As respects the first part of my Invention, the method herein-before
described of preventing or counteracting incrustation in steam boilers or
apparatus for imparting heat to liquids by tlie use or employment
therein of an immersed or submerged picce or pieces of electro-negative
metal in conjunction with means or apparatus for keeping a part or
parts of such piece or pieces of electro-negative metal below the water
line clean and free from deposit or incrustation.

page_text: And as respects that part of my Invention which relates to the pre-
venting or counteracting incrustation in and detaching it from steam
boilers or apparatus for imparting heat to liquids by means of a battery,
I claim the use or employment in combination with the submerged or
immersed electrode of such battery of a loose or moveable piece or
pieces, or terminal or terminals, or cleaning device for keeping a part or
parts of the said electrode below the water line clean and free from
deposit or incrustation, substantially as described.
In witness whereof, I, the said Edward Field, have hereunto set
my hand and seal, this Twenty-seventh day of December, in
the year of our Lord One thousand eight hundred and seventy-
three.
9
Witness,
J. J. BROUGHAM,
Clerk to Mr. W. Lloyd Wisc,
Patent Agent,
London.
EDWARD FIELD. (L.S.)