Improvements in the Annealing of Wire, Sheet-metal, and other Articles of Metal.
Year: 1891

page_text: Date of Application, 10th Mar., 1891
Complete Specification Left, 10th Dec., 1891-Accepted, 16th Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements in the Annealing of Wire, Sheet-metal, and other
Articles of Metal.
CARL FRIEDRICH CLAUS, of 88, Yeldham Road, Hammersmith in the County
of Middlesex, Chemist, do hereby declare the nature of this invention to be as
follows:-
The
In a Specification No. 14063 dated the 6th of September 1890, I have described
a process, which has for its object to provide for the annealing of wire, sheet metal
and other articles of metal and for the reduction to the metallic state of the
superficial film of oxide formed thereon without the necessity for the use of acids
or the like, so that I can dispense altogether with the process of pickling.
main feature of the said process consists in passing water gas or hydrogen gas free
from sulphur through the vessels containing the metal articles after they have been
heated and in bringing these gases into contact with the said articles in order to
effect the cooling thereof sufficiently to allow their removal from the annealing
vessels.
It was further stated in the said Specification that in using watergas for the
therein described process, it is principally the hydrogen contained in the same
which effected the reduction of the oxide to the metallic state and also that if the
hydrogen contained in the gases leaving one annealing furnace has not been
sufficiently consumed, the said gases are preferably conveyed into another annealing
furnace in order to use up fully the hydrogen which they contain. The other chief
constituent of the watergas viz. carbonic oxide which passes out of the annealing
vessels unconsumed, I then proposed to use as fuel for producing the heat required
for the annealing of further quantities of metal articles, by either igniting the said
gas in admixture with air and conducting the ignited gaseous mixture into the flues
surrounding the annealing vessels or by admitting such a quantity of air to this
combustible gas, that only a part of the same is burnt, whilst another part remains
unburnt and conducting it into the interior of the annealing vessels so that it comes
into direct contact with the metal articles. The metal articles thus annealed are
then cooled down by passing cold watergas through the same.
In another Specification No. 4279, dated 10th of March 1891, I have described
a process, whereby I am enabled to purify watergas from sulphur compounds,
which consists in conducting the crude watergas as hot as it leaves the producer
through a series of closed vessels containing pieces of metallic iron (or copper)
preferably in the form of spongy iron (or copper). The watergas when leaving the
producer" and before entering the purifier vessels possesses a high temperature,
of which heat little or none is lost whilst passing through and out of the purifier
vessels.
Now according to my present improvement I conduct the hot purified watergas
as it leaves the purifiers into and through the vessels (from one to another) in
which the articles to be annealed are contained and in direct contact with the same.
Its heat is thus made use of since they become annealed thereby.
Should the gas leaving the "producer" and the purifiers respectively, not be
sufficiently hot for the purpose, further heat may be given to it by any suitable
means, as for instance by the means named in the above cited Specification
No. 14063-1890, that is to say by burning a portion of the said gas as therein
described. For cooling down the articles which have been annealed in this manner,
the vessels containing those required to be cooled are disconnected from those
which are being heated (by the hot gas) and cold gas is passed through
the same.

page_text: According to another part of my present improvement I also protect the articles
of metal from oxidation or 1 reduce any oxide which may have been formed on
their surface whilst in a heated state, by conducting watergas or hydrogen gas (free
from sulphur compounds) through the annealing pots or boxes containing the
articles of metal to be annealed, when such pots or boxes are heated from the
outside by means of ordinary fuel.
For this purpose I displace the air contained in the annealing vessels as soon as
they have been filled (with the articles to be annealed) by means of watergas or
hydrogen gas or by other non-oxidising gas to prevent explosion and after that I
connect the same with a gasholder containing the watergas or hydrogen gas. The
current of gas passing away from the gasholder to the annealing vessel or the series
of annealing vessels connected together (by pipes from one to another) I cause
preferably to pass through a watersealed box before it is allowed to enter the
annealing vessel or vessels to prevent a back current. It is admitted into the
vessel which had been charged first, cooling the already annealed articles contained
therein, then passing through those which are being annealed and leaving by the
one which was charged last.
In passing through the latter the gas becomes cooled again to some extent and
may be used after leaving it as fuel for other purposes.
The current of gas passing through the annealing vessels need only be a small
one, but it should be sufficient to cool down to the temperature of the air, or so, the
articles contained in the firstly charged vessel. After leaving the lastly charged
vessel I may employ the same gas again several times for the same use and for that
purpose I pass it through a set of cooling pipes into another gasholder from which
it may be again conveyed through more annealing vessels.
London, the 10th of March 1891.
COMPLETE SPECIFICATION.
Improvements in the Annealing of Wire, Sheet-metal, and other
Articles of Metal.
I, CARL FRIEDRICH CLAUS, of 88, Yeldham Road, Hammersmith, in the
County of Middlesex, Chemist, do hereby declare the nature of this invention and
in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
In the Specification of former Letters Patent dated 6th September 1890,
No. 14,063, I have described a process which has for its object to provide for the
annealing of wire, sheet-metal and other metal articles, and for the reduction to
the metallic state of the superficial film of oxide formed thereon, without the
necessity for the use of acids or the like, so that I can dispense altogether with
the process of pickling. The main feature of the said process consists in passing
water-gas or hydrogen-gas free from sulphur through the vessels containing the
metal articles after they have been heated, and bringing these gases into contact
with the said articles in order to effect the cooling thereof sufficiently to allow of
their removal from the annealing vessels.
In the said Specification, it is stated, that, in using water-gas for the therein
described process, it is principally the hydrogen contained in the same which effects
the reduction of the oxide to the metallic state; and also that, if the hydrogen
contained in the gases leaving one annealing furnace has not been sufficiently
consumed, the said gases are preferably conveyed into another annealing furnace in
order to use up fully the hydrogen which they contain. The other chief constituent
of the water-gas, viz. :-carbonic oxide, which passes out of the annealing vessels
unconsumed, I then propose to use as fuel for producing the heat required for the
annealing of further quantities of metal articles, by either igniting the said gas in
admixture with air and conducting the ignited gaseous mixture into the flues

page_text: surrounding the annealing vessels, or by admitting such a quantity of air to this
combustible gas, that only a part of the same is burnt, whilst another part remains
unburnt, and conducting it into the interior of the annealing vessels so that it comes
into direct contact with the metal articles. The metal articles thus annealed are
then cooled down by passing cold water-gas through the same.
In the Specification of Letters Patent dated 10th March 1891, No. 4279, I have
described a process whereby I am enabled to purify water-gas from sulphur
compounds, which process consists in conducting the crude water-gas hot as it
leaves the "producer," through a series of closed vessels containing pieces of
metallic iron (or copper) preferably in the form of spongy iron (or copper). The
water-gas, when leaving the "producer" and before entering the purifier vessels, is
at a high temperature, and little or none of its heat is lost whilst it is passing
through and out of the purifiers.
Now, according to one part of my present invention, I conduct the hot purified
water-gas, as it leaves the said purifiers, into and through the vessels (from one to
another) in which the articles to be annealed are contained, and in direct contact
with the same. Its heat is thus made use of in the annealing process to ensure the
reduction of the oxide of the metal.
Should the gas leaving the "producer " and the purifiers respectively, not be
sufficiently hot for the purpose, further heat may be imparted to it by any suitable
means, as, for instance, by the means described in the aforesaid Specification
No. 14,063 of 1890, that is to say, by burning a small portion of the said gas as
therein described. For cooling down the articles which have been annealed in this
manner, the vessels containing those required to be cooled are disconnected from
those which are being heated (by the hot gas) and cold gas purified as above
described is passed through the vessels in which the articles are to be cooled.
According to another part of my present invention, I protect the metal articles
from oxidation, or I reduce any oxide which may have been formed on their surface
whilst in a heated state, by conducting water-gas or hydrogen-gas (free from
sulphur compounds) through the annealing pots or vessels containing the metal
articles to be annealed, whilst such pots or vessels are heated from the outside by
means of ordinary fuel or in any other convenient manner, the gas being first passed
through one or more purifiers as above specified.
For this purpose, I displace the air contained in the annealing vessels (as soon
as they have been filled with the articles to be annealed) by means of water-gas or
hydrogen-gas or by other non-oxidising gas, to prevent explosion; I then connect
the said vessels with a gasholder containing the water-gas or hydrogen-gas, or with
any other suitable gas-supply, whilst applying heat externally to the said vessels as
above stated. The current of gas passing to the annealing vessel or to the series
of annealing vessels connected together by pipes extending from one to another, I
cause preferably to pass through a water-sealed box, before it is allowed to enter
the annealing vessel or vessels, in order to prevent a back current.
The gas is
admitted into the vessel which had been charged first, and, after cooling the already
annealed articles contained therein, passes through the vessels in which the articles
are being annealed, and leaves by the one which was charged last.
In passing through the latter, the gas becomes cooled again to some extent and
may be used after leaving it as fuel for various purposes, for instance, for heating
externally other annealing pots or vessels.
The water-gas or other gas used in carrying out the second part of my said
invention, may be admitted to the externally heated annealing pots or vessels either
in a cold state or heated to a suitable temperature.
The current of gas passing through the annealing vessels need only be a small
one, but it should be sufficient to cool down to the temperature of the air, or nearly
so, the articles contained in the firstly charged vessel. After leaving the lastly
charged vessel I may employ the same gas again several times for the same use,
and for that purpose I pass it through a set of cooling pipes into another gas-holder
from which it may be conveyed through more annealing vessels.

page_text: 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 :
First. A method or process, such as I have hereinabove described, of annealing
metal articles, by passing hot crude water-gas or other producer-gas first through
one or more purifiers containing metallic iron or copper in a finely divided state
(such as iron or copper sponge) and then through the annealing pots or vessels.
Second. In the annealing of metal articles, the herein described method or
process of preventing the formation of oxide on the said articles, or reducing any
oxide that may be formed thereon, by passing cold or hot water-gas or other
producer-gas first through one or more purifiers containing metallic iron or copper
in a finely divided state, and then through the annealing pots or vessels whilst the
same are heated externally.
Third. In the annealing of metal articles, the herein described method of cooling
the heated articles sufficiently to permit their removal from the annealing pots or
vessels, by passing water-gas or other producer-gas first through one or more
purifiers containing metallic iron or copper in a finely divided state, and then
through the annealing pots or vessels, as above specified.
D. Young & Co.,
C. F. CLAUS.
11 & 12, Southampton Buildings, W.C., Agents for the Applicant.