IMPROVEMENTS IN PREVENTING THE CORROSION OF WATER PIPES AND OTHER METAL ARTICLES OR STRUCTURES LIABLE TO THE ACTION OF MOISTURE AND IN APPARATUS THEREFOR "
Year: 1883

page_text: LETTERS PATENT to James Ballantyne Hannay, of Glasgow, in the County of
Lanark, North Britain, Chemist for an Invention of "IMPROVEMENTS IN
PREVENTING THE CORROSION OF WATER PIPES AND OTHER METAL ARTICLES
OR STRUCTURES LIABLE TO THE ACTION OF MOISTURE AND IN APPARATUS
THEREFOR
"
PROVISIONAL SPECIFICATION left by the said James Ballantyne Hannay
at the Office of the Commissioners of Patents on the 10th May 1883.
•
JAMES BALLANTYNE HANNAY, of Glasgow, in the County of Lanark, North
Britain, Chemist, "IMPROVEMENTS IN PREVENTING THE CORROSION OF WATER
PIPES AND OTHER METAL ARTICLES OR STRUCTURES LIABLE TO THE ACTION OF
MOISTURE AND IN APPARATUS THEREFOR
"
This Invention has for its object to prevent the corrosion of water pipes and
other metal articles or structures liable to the action of moisture; and it consists
in causing an electric current obtained by means of any suitable galvanic battery
or dynamo-electric machine to pass through the metal of the pipe or other article
or structure which it is wished to protect from corrosion, in such a manner as to
render the said metal relatively electro-negative.
In the case of water pipes embedded in earth the metal may be protected both
internally and externally, in other words from the corrosive action of the water
passing through it and from the action of any moisture in the earth or otherwise
external to it. In the case of gas pipes or other pipes conveying non-corrosive
fluids it will be sufficient to apply the electric protection only to the outside.
Outside protection will be sufficient also for many other structures such as the
cylindrical iron piers of bridges, and any metal structures which may be wholly or
partly submerged in water or earth.
In carrying out the Invention in the case of water pipes, tanks, cisterns and the
like, the metal is connected by a suitably insulated conductor to the negative pole
or terminal of the galvanic battery or dynamo-electric machine; and the positive
pole or terminal thereof is connected by a suitably insulated conductor to an
electrode of carbon or other suitable substance placed in the water inside of the

page_text: pipe, tank, or cistern, being inserted, if necessary or convenient, through a stuffing
box formed through the metal of the pipe, tank, or cistern. This will protect the
inside from corrosion; and to protect the outside a shunt or separate conductor
from the positive pole or terminal is connected to a plate or piece of carbon or other
suitable substance to act as an electrode and which is embedded in the earth near
the pipe, tank, or cistern. A number of pipe lengths may be protected by means
of one electric current provided the lengths are in metallic contact at their joints
or are connected by conducting wires.
In applying the Invention to water pipes, tanks, or cisterns of lead there is the
important advantage that the electric current will prevent the lead or any
compound of it from being dissolved in the, water, and will even tend to separate
lead from the water should there be any in solution.
Where only outside protection is required the metal of the article or structure is
connected by a metallic conductor to the negative pole or terminal of the galvanic
battery or dynamo-electric machine; and near the article or structure there is
immersed in the water or embedded in the earth one or more carbon or other
electrodes connected to the positive pole or terminal.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by.
the said James Ballantyne Hannay in the Great Seal Patent Office on the
6th November 1883.
JAMES BALLANTYNE HANNAY, of Glasgow; in the County of Lanark, North.
Britain, Chemist "IMPROVEMENTS IN PREVENTING THE CORROSION OF WATER
PIPES AND OTHER METAL ARTICLES OR STRUCTURES LIABLE TO THE ACTION OF
MOISTURE AND IN APPARATUS THEREFOR."
My said Invention has for its object to prevent the corrosion of water pipes and.
other metal articles or structures liable to the action of moisture; and it consists in
causing an electric current obtained by means of any suitable galvanic battery or.
dynamo-electric machine to pass through the metal of the pipe or other article or
structure which it is wished to protect from corrosion, in such a manner as to render
the said metal relatively electro-negative.
In the case of water pipes embedded in earth the metal may be protected both
internally and externally, in other words from the corrosive action of the water
passing through it and from the action of any moisture in the earth or otherwise
external to it. In the case of gas pipes or other pipes conveying non-corrosive
fluids it will be sufficient to apply the electric protection only to the outside.
Outside protection will be sufficient also for many other structures, such as the
cylindrical iron piers of bridges, and any metal structures which may be wholly or
partly submerged in water or earth.
In carrying out the Invention in the case of water pipes, tanks, cisterns and the
like, the metal is connected by a suitably insulated conductor to the negative pole
or terminal of the galvanic battery or dynamo-electric machine; and the positive
pole or terminal thereof is connected by a suitably insulated conductor to an
electrode of carbon or other suitable substance placed in the water inside of the
pipe, tank, or cistern, being inserted, if necessary or convenient, through a stuffing
box formed through the metal of the pipe, tank, or cistern. This will protect the
inside from corrosion; and to protect the outside a shunt or separate conductor
from the positive pole or terminal is connected to a plate or piece of carbon .or
other suitable substance to act as an electrode and which is embedded in the earth
near the pipe, tank, or cistern. A number of pipe lengths may be protected by
means of one electric current provided the lengths are in metallic contact at their
joints or are connected by conducting wires.
In applying the Invention to water pipes, tanks, or cisterns of lead there is the
important advantage that the electric current will prevent the lead or any
compound of it from being dissolved in the water, and will even tend to separate
lead from the water should there be any in solution.
Where only outside protection is required the metal of the article or structure is
connected by a metallic conductor to the negative pole or terminal of the galvanic
battery or dynamo-electric machine; and near the article or structure there is
immersed in the water or embedded in the earth one or more carbon or other
electrodes connected to the positive pole or terminal.
In practically applying my Invention the strength and quantity of electric
current required will vary in different cases, and will depend upon the nature or
quality of the iron or other metal forming the pipes, tanks, or other vessels and
upon various conditions and circumstances. As a guide I may state that a galvanic
battery or dynamo-electric machine yielding a current of about 10 amperes, of an
electromotive force of 25 volt, will be sufficient for protecting an iron tank or, a
length of piping having 150 square feet of surface wetted by water such as ordinary

page_text: rain or spring water. If the carbon or other electrode in contact with the water
is passed through the metal of the tank or piping it must be with an insulating
material at the part where it passes through and also at other parts where it may
be in contact with supports of a conducting nature. The conducting wire from the
source of electricity must be carefully fixed to the metal to be protected, solder
being by preference employed; and where two or more pieces are to be protected
by means of one current they must be connected by solder or otherwise in a manner
to insure complete conduction.
1
An..
Having thus particularly described my said Invention and the manner of
performing the same I have to state that I do not restrict myself to the precise
details hereinbefore described but that what I believe to be novel and original and
claim as the Invention secured to me by and in terms of the hereinbefore in part
recited Letters Patent is :-
Preventing the corrosion of water pipes and other metal articles or structures.
liable to the action of moisture by rendering the metal of such articles or structures
électro-negative by means of the apparatus and in the manner substantially as
herein before described.
:
1
.
In Witness whereof I, the said James Ballantyne Hannay, have hereunto set
my hand and seal this fifth day of November, in the year of our Lord One
thousand eight hundred and eighty-three.
Witness
EDMUND HUNT
Patent Agent
Glasgow.
B HANNAY (LS)