IMPROVEMENTS IN APPARATUS FOR PREVENTING CORROSION IN BOILERS AND OTHER METALLIC VESSELS to be as follows:
Year: 1884

page_text: PROVISIONAL
DI MUIFICATION.
I, JAMES BALLANTYNE HANNAY, of Cove Castle, Loch Long, in the County of
Dumbarton, North Britain, Chemist, do hereby declare the nature of my said
invention for "IMPROVEMENTS IN APPARATUS FOR PREVENTING CORROSION IN
BOILERS AND OTHER METALLIC VESSELS to be as follows:―
"
My present Invention has for its object to render more convenient and efficient
in certain special cases and circumstances, the practical application of the modes of
preventing the corrosion of boilers and other vessels described in the Specifications
of patents granted to me and bearing the following official numbers 2544 of 1881,
5873 of 1882, and 2376 of 1883.
In the modes referred to, of preventing corrosion, special forms of zinc blocks
are connected by conducting wires to the plates or other parts of the boiler or vessel
to be protected, the zinc blocks being placed in the water in the boiler or in water
or liquid in the vessel or otherwise in contact with the metal thereof. In the
special cases to which the present Invention relates the water or liquid contained
in the vessel is of such a kind that the desired galvanic or electric action does not
take place sufficiently unless sodium chloride or other suitable salt or chemical
agent is in solution in the water or liquid which is in contact with the zinc block.
In the case of a steam boiler using fresh water the quantity of salt required for
forming a sufficiently strong solution with the whole of the water is greater than
is desirable or really necessary, whilst in the case of some liquids the presence of
the salt or chemical agent throughout the liquid is quite inadmissible. By my
present Invention a small quantity of the salt or chemical agent is rendered
efficient by enclosing the zinc block in a small vessel of metal or other impermeable
material the salt or chemical agent in solution or partly in solution being also put
into such small vessel; and in immersing this small vessel in the water or liquid
of the boiler or vessel to be protected. The zinc may be insulated by pieces of
wood or other nonconductor from the sides of the small, vessel so as to prevent
short-circuiting. The conducting wire or wires from the zinc are to be led out
through a small opening in the top of the small vessel and this opening may other-
wise be closed with asbestos in such a manner that communication between the
liquid in the small vessel and the surrounding water or liquid in the boiler or large
vessel may be no greater than is absolutely necessary.
Dated this coventh day of February 1884
EDMUND HUNT,
Applicant's Agent,

page_text: I, JAMES BALLANTYNE HANNAY, of Cove Castle, Loch Long, in the County of
Dumbarton, North Britain, Chemist, do hereby declare the nature of my said
invention for "IMPROVEMENTS IN APPARATUS FOR PREVENTING CORROSION IN
BOILERS AND OTHER METALLIC VESSELS and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement that is to say:-
e
"
My present Invention has for its object to render more convenient and efficient
in certain special cases and circumstances, the practical application of the modes of
preventing the corrosion of boilers and other vessels described in the Specifications
of patents granted to me and bearing the following Official numbers, 2544 of 1881,
5873 of 1882 and 2376 of 1883.
".
In the modes referred to, of preventing corrosion, special forms of zinc blocks
are connected by conducting wires to the plates or other parts of the boiler or
vessel to be protected the zinc blocks being placed in the water in the boiler or in
water or liquid in the vessel or otherwise in contact with the metal thereof. In
the special cases to which the present Invention relates the water or liquid contained
in the vessel is of such a kind that the desired galvanic or electric action does not
take place sufficiently unless sodium chloride or other suitable salt or chemical
agent is in solution in the water or liquid which is in contact with the zinc block.
In the case of a steam boiler using fresh water the quantity of salt required for
forming a sufficiently strong solution with the whole of the water is greater than is
desirable or really necessary, whilst in the case of some liquids the presence of the
salt or chemical agent throughout the liquid is quite inadmissible. By my present
Invention a small quantity of the salt or chemical agent is rendered efficient by
enclosing the zinc block in a small vessel of metal or other impermeable material,
the salt or chemical agent in solution or partly in solution being also put into such
small vessel; and in immersing this small vessel in the water or liquid of the
boiler or vessel to be protected. The zinc may be insulated by pieces of stone,
wood, or other nonconductor from the sides of the small vessel so as to prevent
short-circuiting. The conducting wire or wires from the zinc are to be led out
through a small opening in the top of the small vessel and this opening may other-
wise be closed with asbestos in such a manner that cominunication between the
liquid in the small vessel and the surrounding water or liquid in the boiler or large
vessel may be no greater than is absolutely necessary.
And in order that my said Invention and the manner of performing the samė
may be properly understood I hereunto append a sheet of explanatory drawings to
be hereinafter referred to.
Figure, 1, is a transverse vertical section of a cominon form of land boiler having
two flues; A, A, whilst figure, 2, is an enlarged section showing the zinc block and
chemical agent enclosed in their containing vessel, B. Figures, 3, and 4, are
sectional side and end elevations of a boiler of the locomotive type; and figure, 5,
is an enlarged section of the zinc block, and its containing vessel suitable for that
kind of boiler. In these drawings the same reference letters are used to mark the
same or like parts wherever they are repeated.
In the modification suitable for ordinary boilers and shown in figures, 1, and 2,
the zinc block E; which is known by the name of "Electrogen," cast on its copper
core, C, is placed inside of a bottle-shaped vessel, B, which may be made of sheet
iron. This vessel is made in two parts having flanges, F, to be joined by screws or
rivets after the electrogen, E, is placed inside. Pieces, G, of stone, or any non-

page_text: conducting substance are placed so as to prevent the electrogen from touching the
bottom or sides of the vessel; and the neck, H, through which the copper core, C,
projects is plugged with fibrous asbestos after the salt, in a crystallised state, has
been put into the vessel and the vessel filled up with water. Ordinary chloride
of sodium may be used but I prefer to employ one half of that salt and the other
half of chloride of ammonium. The vessel, B, is placed between the flues, A, A,
as shown in figure, 1, being partly supported by extensions of the flanges, F; and
the conducting wires, K, which are carefully soldered to the copper core, C, are led
and soldered to the tops of the flues, A, A.
In a boiler of the locomotive type such as is shown in figures, 3, and 4, the space
in which the electrogen, E, has to be put, namely between the tubes and the side
of the boiler, being extremely confined, the electrogen, E, and its vessel, B, are
made of an elongated form as fully shown in figure, 5, there being an electrogen
placed at each side of the boiler as shown in figure, 4. Each vessel, B, is made in
halves which are united by vertical flanges, and each vessel is supported on a shelf
or ledge, L, riveted to the side of the boiler.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is:
The mode of applying zinc blocks to prevent corrosion and incrustation in steam
boilers, according to which each block is enclosed along with chloride of sodium or
other suitable salt in a vessel of metal or non-porous material, a copper core on
which the block is cast being arranged to project through a neck which is plugged
with fibrous asbestos, and the said copper core having soldered to it one or more
conductors soldered at the other end to a part or parts of the boiler, substantially
as herein before described.
DL:
1001
EDMUND HUNT,
Applicant's Agent.