AN IMPROVED PROCESS FOR COATING IRON WITH ZINC OR TIN, OR COMPOUNDS THEREOF, WHICH INVENTION COMPRISES AN ALLOY AND SOLUTIONS TO BE USED IN SUCH PROCESS
Year: 1880

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for an Invention of
"AN IMPROVED PROCESS FOR COATING IRON WITH ZINC OR TIN, OR
COMPOUNDS THEREOF, WHICH INVENTION COMPRISES AN ALLOY AND
SOLUTIONS TO BE USED IN SUCH PROCESS." A communication from abroad
by John Benbow Jones, Metallurgist, and Henry Wardwell Shepard, Manu-
facturer, both of Brooklyn, and Robert Seaman, of the City of New York,
Merchant, all in the State of New York, United States of America.
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 15th September 1880.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent
Agents, Southampton Buildings, London. "AN IMPROVED PROCESS FOR COATING
IRON WITH ZINC OR TIN, OR COMPOUNDS THEREOF, WHICH INVENTION COMPRISES
AN ALLOY AND SOLUTIONS TO BE USED IN SUCH PROCESS." [A communication
from abroad by John Benbow Jones, Metallurgist, and Henry Wardwell Shepard,
Manufacturer, both of Brooklyn, and Robert Seaman, of the City of New York,
Merchant, all in the State of New York, United States of America.]
This Invention includes a process comprising the use of a neutralizing bath,
hereinafter described, for preparing sheets or other iron articles to be coated after
the usual pickling or cleaning operation has been performed, and previous to
immersion in the metallic bath, for the purpose of decomposing the injurious ferric
salts from the fibres of the iron, thereby removing an injurious and destructive
element to the durability of the iron through deliquescence and exposure to moist
atmospheres.
It also comprises the use of a flux bath for the purpose of removing any oxida-
tion or preventing its formation as the sheets or articles are passed into the metal
bath, thereby rendering unnecessary the use of muriatic acid and drying the same
in an oven or otherwise, as now practised, to the great injury of the texture of the
iron, and also the great deterioration of the metal from the admixture of iron

page_text: resulting from the decomposition of that portion of the dried ferric salts remaining
upon the surface.
It further comprises a special alloy of zinc, tin, lead, and nickel, to be applied to
the prepared articles as a metal bath.
The said improved preparatory process may be profitably used with the ordinary
bath of melted zinc, although it is especially adapted to the aforesaid new alloy
of zinc, tin, lead, and nickel. And this alloy may be used in connection with
other preparatory or neutralizing processes.
I will describe the said improvements as used in coating sheet iron with the
above named-new alloy of zinc, tin, lead, and nickel. The operations according to
this Invention are carried into practice as follows, that is to say :-
The sheets of iron are first cleaned to remove the scale and dirt in the ordinary
bath of dilute acid, and are then washed in clear water and inspected as in the
common process of "galvanizing." The sheets thus washed are then put into a
bath of water containing about one or two per cent. of any fusible, metallic, or
organic chloride, whose hases are positive to iron, such as methyl or ethylamine
chlorides, ammonium or zinc chloride. Into (say about 100 gallons) of this
solution I stir about 4 or 5 pounds of the oxide or surface dross of the metal or
alloy intended to be used as the metal bath. The addition of this oxide furnishes
an element contained in that portion of zinc of which it is composed, which
materially assists in decomposing the ferric salts in the iron, forming a positive
-element_to_the_negative ferric salts, as thero always remains a sufficient amount of
free acid in the pores of the iron to excite action-although it may have been washed
in water. In use the temperature-most suitable is about 120° Fahrenheit. The
sheets of iron when taken from the clear water bath are put-into-this-bath,
remaining for a short time, say, ten or fifteen minutes, or until the next lot of
sheets or articles from the water bath is ready. The action of this bath or solution
of chlorides and metallic oxides is to decompose the ferric salts and neutralize free
acid contained in the pores of the iron after leaving the first bath of sulphuric (or
muriatic) acid. The ferric salts are infusible at the temperature of the metal bath,
and unless they are decomposed or removed they will remain in the iron and cause
rust or otherwise injure it by its subsequent decomposition after the metal coating
has been applied.
The sheets undried are then taken from this bath and at once put into another
or flux bath, composed of about equal volumes of water and any chlorides of the
organic or metallic bases whose salts are fusible at the temperature of the metallic
bath. Instead of this bath I may use a bath composed in the proportion of one
gallon of water, two pounds of chloride of ammonium (sal ammoniac), and one
gallon of dissolved chloride of zinc.
The surface of this last bath should be covered to a depth of two or three inches
with napthaline oil or any other fusible substance capable of combining with
chlorine in a heated condition. As the sheets come from this last bath they are
immersed without drying in. the usual manner into the bath of melted zinc or ziuc
alloy, when the desired coating is obtained.
This process of preparing the iron sheets or other articles is a valuable improve-
ment when the metal bath is zine, and it is equally or more valuable when the
metal bath is of the alloy of zinc, tin, lead, and nickel, or tin only, or iron coating
of any kind.
The improved alloy or compound metal made according to this Invention is
especially adapted for use as a metal bath into which iron sheets or other articles
are to be immersed, and thereby coated so as to prevent oxidation. The pro-
portions may be somewhat varied, but the following is one of the best modes of
compounding my improved alloy, that is to say:-I first melt in a large crucible in
the proportion from 3 to 6 ounces of nickel; into this crucible I pour from 3 to
6 pounds of melted lead, and mix the two metals thoroughly. This melted mixture
is then poured into a melting pot containing from 94 to 98 pounds of melted lead.
Into this pot of nickel and lead I put about from 50 to 75 pounds of zinc, and mix

page_text: thoroughly into this mixture I then melt and thoroughly mix about 29 pounds of
tin. This alloy thus made may be cast into ingots and be remelted as desired, or
it may be at once poured into the metal bath or kettle.
After the nickel and lead are melted and mixed together it is better to introduce
the zinc and then the tin in ingots near the bottom of the melted metal by dropping
the pieces through a cylinder, having its upper end above the edge of the pot and
its lower end near the bottom of the pot. This mode of introducing the zinc and
tin facilitates a more thorough mixture.
By this Invention I am enabled to use a large quantity of lead in combination
with the zinc, tin, and nickel, and yet have the alloy remain electro-positive to the
iron (or nearly so).
•
Metal coated by this. Invention is as well or better protected against oxidation,
and its durability and tenacity is not injured to anything like the extent that
occurs when coated with zinc alone, and the conting itself is moro flexible. The
metal bath of this alloy is efficient at a lower temperature than when zinc only is
used. When zine only is used the hot melted zinc acts upon the iron in such a
manner as to dissolve from the iron a quantity of its surface, which combining
with a portion of the zinc becomes a heavy infusible dross, chiefly consisting of
iron and zinc, which falls to the bottom of the metal bath and interferes with the
proper action of the bath, necessitating its constant removal, and is a source of
great waste, as it is difficult to dispose of it at less than half its original cost. The
said improved alloy has a greater fluidity than zinc only, and an efficient coating
can be made with a smaller per centage of metal than with zinc, so that less
weight is imparted to articles coated according to this Invention.
The combined action of my neutralizing bath and flux bath so thoroughly cleans
the iron and frees it from infusible ferric salts and iron oxides as to ensure a perfect
chemical union between the iron and the coating metal without the use of the
ordinary drying chamber and free muriatic acid.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Robert Lake in the Great Seal Patent Office on the
15th March 1881.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent
Agents, Southampton Buildings, London. "AN IMPROVED PROCESS FOR COATING
IRON WITH ZINC OR TIN, OR COMPOUNDS THEREOF, WHICH INVENTION COMPRISES
AN ALLOY AND SOLUTIONS TO BE USED IN SUCH PROCESS." A communication
from abroad by John Benbow Jones, Metallurgist, and Henry Wardwell Shepard,
Manufacturer, both of Brooklyn, and Robert Seaman, of the City of New York,
Merchant, all in the State of New York, United States of America.
This Invention embodies a process comprising the use of a neutralizing bath,
hereinafter described, for preparing sheets or other iron articles to be coated after
the usual pickling or cleaning operation has been performed, and previous to
immersion in the metallic bath, for the purpose of decomposing the injurious ferric
salts from the fibres-of-the-iron, thereby-removing an-injurious-and-destructive:
element which impairs the durability of the iron through deliquescence by exposure
_to_moist atmospheres.
The said Invention also comprises the use of a Bux-bath for the purpose-of-
removing any oxide or preventing-its-formation-as-the-sheets-or-articles-are-passed-
into the metal bath, thereby rendering unnecessary the use of muriatic acid and
the drying of the said sheets or articles in an oven or otherwise as now practised,
to the great injury of the texture of the iron, and also the great deterioration of the.
metal by the admixture of iron resulting from the decomposition of that portion of
the dried ferric salts remaining upon the surface.
The said Invention further comprises a special alloy of zinc, tin, lead, and nickel
to be applied to the prepared articles as a metal-bath.
The said improved preparatory process may be profitably used with the ordinary
bath of melted zinc, although it is especially adapted to the aforesaid new alloy of
zinc, tin, lead, and nickel. And this alloy may be used in connection with other
preparatory or neutralizing processes.
I will first describe the said improvements as used in coating sheet iron with
the above named new alloy of zinc, tin, lead, and nickel.
For this purpose the
sheets of iron are first cleaned to remove the scale and dirt in the ordinary bath of
dilute acid, and are then washed in clean water and inspected as in the common
process of "galvanizing." The sheets thus washed are then put into a bath of
water containing about one or two per cent. of any fusible metallic or organic
chloride whose bases are positive to iron, such as methyl or ethylamine chlorides,
ammonium or zinc chloride. Into, say, about 100 gallons of this solution I stir
about 4 or 5 pounds of the oxide or surface dross of the metal or alloy intended to
be used as the metal bath. The addition of this oxide furnishes an element
contained in that portion of zine of which it is composed, which materially assists in
decomposing the ferric salts in the iron, forming a positive element to the negative
ferric salts, as there always remains a sufficient amount of free acid in the pores of the
iron to excite action although it may have been washed in water. In use the
temperature most suitable is about 120° Fahrenheit; the sheets of iron when taken
from the clear water bath are put into this bath, remaining for a short time, say,
ten or fifteen minutes, or until the next series of sheets or articles from the water
bath is ready. The action of this bath or solution of chlorides and metallic oxides
is to decompose the ferric salts and neutralize the free acid contained in the pores
The ferric
of the iron after leaving the first bath of sulphuric (or muriatic) acid.
salts are infusible at the temperature of the metal bath, and unless they are
decomposed or removed they will remain in the iron and cause rust or otherwise

page_text: injure by their subsequent decomposition alter the metal coating has been
applied.
The sheets undried are then taken from this bath and at once put into another
or flux bath composed of about equal volumes of water and any chlorides of the
organic or metallic bases whose salts are fusible at the temperature of the metal
bath. Instead of this bath I may use a bath composed in the proportion of one
gallon of water, two pounds of chloride of ammonium (sal ammoniac), and one
gallon of dissolved chloride of zinc.
The surface of this last named bath should be covered to a depth of two or three
inches with naphthaline oil or any other fusible substance capable of combining with
chlorine in a heated condition. As the sheets come from this last bath they are
immersed without drying in the usual manner in the bath of melted zinc or zinc
alloy, when the desired coating is obtained.
This process of preparing the iron sheets or other articles is a valuable improve-
ment when the metal bath is zinc, and it is equally or more valuable when the
metal bath is comp sed of the alloy of zinc, tin, lead, and nickel, or tin only, or iron
coating of any kind.
The improved alloy or compound metal made according to this Invention is
especially adapted for use as a metal bath into which iron sheets or other articles are
to be immersed and thereby coated so as to prevent oxidation. The proportions may
be somewhat varied, but the following is one of the best modes of compounding my
improved alloy, that is to say-I first melt in a large crucible from 3 to 6 ounces of
nickel;
into this crucible I pour from 3 to 6 pounds of melted lead, and mix the
two metals thoroughly. This melted mixture is then poured into a melting pot
containing from 94 to 98 pounds of melted lead. Into this pot of nickel and lead I
put about from 50 to 75 pounds of zinc and mix thoroughly; into this mixture I then
melt and thoroughly mix about 29 pounds of tin. The alloy thus made may be
cast into ingots and be re-melted as desired, or it may be at once poured into the
metal bath or kettle. After the nickel and lead are melted and mixed together it is
preferable to introduce the zinc and then the tin in ingots near the bottom of the
melted metal by dropping the pieces through a cylinder having its upper end
above the edge of the pot and its lower end near the bottom of the suid pot.
This mode of introducing the zinc and tin facilitates a more thorough mixture.
By this Invention I am enabled to use a large quantity of lead in combination
with the zinc, tin, and nickel, and yet have the alloy remain electro-positive to the
iron or nearly so.
Metal coated by this Invention, which I term "calamining," is as well or better
protected against oxidation as when coated with zinc alone, moreover its durability
and tenacity are not injured to anything like the extent that occurs when coated
with zinc alone, and the coating itself is more flexible. The metal bath of this
When zinc,
alloy is efficient at a lower temperature than when zinc only is used.
only is used the hot melted zinc acts upon the iron in such a manner as to dissolve
from the iron a quantity of its surface, which, combining with a portion of the zinc,
becomes a heavy infusible dross, chiefly consisting of iron and zinc, which falls to
the bottom of the metal bath and interferes with the proper action of the bath,
necessitating its constant removal, and is a source of great waste, as it is difficult
to dispose of it at more than half its original cost. The said improved alloy has a
greater Huidity than zinc only, and an efficient coating can be made with a smaller
percentage of metal than with zinc, so that less weight is imparted to articles
coated according to this Invention.
The combined action of my neutralizing bath and flux bath so thoroughly cleans
the iron and frees it from infusible ferric salts and iron oxides as to ensure a perfect
chemical union between the iron and the coating metal without the use of the
ordinary drying chamber and free muriatic acid.
Having thus fully described the said Invention, as communicated to me by my

page_text: foreign correspondents, and the manner of performing the same, I wish it understood
that I claim,-
First. The alloy of nickel, lead, tin, and zinc compounded, substantially as herein
set forth and for the purposes specified.
Second. A neutralizing bath composed of the chlorides of the organic or metallic
bases positive to iron in connection with similarly related metallic oxides for the
purpose of decomposing ferric salts in iron articles previously cleaned in dilute
muriatic or sulphuric acid, substantially as above set forth and for the purpose.
specified.
Third. The flux bath composed of water and chlorides of organic and metallic
bases whose salts are fusible at the temperature of the metal bath when covered
with naphthaline oil or other substances easily fusible and capable of combining
with heated chlorine, substantially as above set forth and for the purpose specified.
Fourth. The improved process herein set forth of coating iron with the alloy
specified or its equivalent by means of the cleaning bath, the neutralizing bath,
the flux bath, and the metal bath, substantially as above set forth and for the
purposes specified,
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand-and-seal,_this_Fifteenth-day of March, in the year of our Lord. One
thousand eight hundred and eighty one.