A New and Improved Process for Welding Metals.
Year: 1899

page_text: Date of Application, 11th Sept., 1899
Date of Application, 11th Sept., 1899
Complete Specification Left, 9th June, 1900—4ccepted, 25th Aug., 1900
A New and Improved Process for Welding Metals.
I, Dr. HANS GOLDSCHMIDT, of Essen on the Ruhr, in the Province of West.
phalia, in the German Empire, Chemist, do hereby declare the nature of this
invention to be as follows:-
The present application relates to a process for welding metal pieces which,
with respect to the processes hitherto employed offers two important differences,
viz.:
1.ly) the welding is effected while the material is in a state of rest,
2ndly) the molecular expansion of the metal itself is employed for effecting
the welding pressure.
blow
With the processes hitherto employed in practice, the metal pieces to be
welded had to effect a certain movement in the moment when they attained
the welding temperature, the welding itself being effected by a
or by pressure. Whilst in the old welding processes it was neces-
sary to heat the material and then to bring it into the welding
position, according to
invention just
my
the contrary is done,
namely the pieces to be welded beforehand are adjusted and during the weld-
ing itself remain in the same position. This end is attained in effecting the
initial heating by means of a highly heated mass resulting from the reaction
of aluminum, or aluminum and magnesium, or carbides in combination with
metal compounds, preferably oxygenous compounds (this being the second
essential point of my invention).
In order to execute my process it is in the first place necessary to press in a
cold state the metal pieces to be welded one against the other in such manner,
that a displacement during the heating of the mass is rendered impossible, and
the energy introduced by the heating at the welding place acts as welding
pressure.
The process in this simple form is described hereinafter, the example relating
to the welding of shafts or round bars.
The thoroughly cleaned end surfaces of the shafts are pressed one against the
other and are surrounded by a suitable mould of sand or metal in such manner,
that the mould being open at its top covers the whole joint.
A mixture of aluminum and for instance oxide of iron is heated and brought
to reaction in a special crucible. As soon as the reaction is completed and the
contents of the crucible consists of pure iron covering the bottom and a floating
layer of molten alumina, the same is cast upon the joint of the shaft prepared
beforehand. Owing to this heat firstly the welding part attains the welding
temperature and secondly the clamped shaft expands in such manner that a
high molecular pressure is created at the welding part, this pressure effecting
the proper welding.
With my process evidently a certain jolting takes place at the welding part,
the consequence hereof is a contraction of the shafts, in the first place between

page_text: the clamps of the clamping apparatus, and in the second place of the whole shaft.
A dangerous consequence of this contraction of the shafts, when the unclamped
part of the shaft is not able to follow, is the breakage of the welded part. This
drawback can be obviated when the clamps surrounding the shaft are loosened
at the moment when the contraction commences, i.e. in the moment when the
shaft commences to cool after the welding is completed. In consequence of the
loosening of the clamps the shaft becomes movable within the clamping
apparatus. The loosening can be effected either by hand or automatically;
in the latter case the clamping apparatus may consist of elastic tension rods in
which springs are set under tension during the expansion of the material, which
springs become discharged again, when the metal contracts. Also in this case
it is supposed that the whole shaft is able to follow the contraction, this would
be the case with a new installation of railway lines, with rails placed upon
broken stones and in most cases where free metal pieces are to be welded.
When the pieces to be welded are, fixed to some apparatus or are clamped so
strongly that they cannot effect a contraction, the process must be modified.
In this case it is absolutely necessary that the jolting of the rail and its con-
traction being the natural consequence of the jolting is prevented. This can
be attained in two different manners: either the rails are slightly and without
pressure arranged one against the other and the pressure at the welding part
is produced only when the welding heat itself is attained, so that every pres-
sure during the jolting temperature is prevented. The point of welding heat
can easily be ascertained by suitable tests and experiments relating to the pro-
portion of expansion of the rail which clearly and distinctly indicate the time
at which the real welding temperature is attained. In this case the clamping
apparatus is only applied to the rails at the last moment of the welding heat,
.e. shortly before commencement of the cooling. In this manner the con-
traction of the rail at the welding part is prevented.
Another modification of the process for attaining the same purpose consists
in removing the welding surfaces touching another by means of suitable
apparatus to such a distance, that owing to the expansion of the rails during
the increased temperature they approach each other to such a degree that only
in the last state of welding heat they touch each other with a certain pressure,
whilst an earlier contact, as long as the rails only are of jolting temperature,
does not take place. When after the completed welding owing to the cooling
and to the contraction of the rail, the same is liberated from the clamps, the
rail adopts its former exact length.
The process described heretofore with respect to the welding processes hitherto
employed offers the following important advantages:
It is possible to press on a piece of metal in a cold state against another and
to weld same in the same position. This adjustment is impossible with all other
processes in which after the material has reached the necessary temperature 'the
welding is effected by means of an outside pressure or of blows. This is essen-
tially so in the welding of tubes and more especially of tubes having thin walls,
a manipulation which hitherto practically could not be executed at all.
A further advantage must be seen in the fact that the welding part, after
the reaction mass is cast over it, is covered by a layer of alumina which immedi-
ately becomes stiff, whereby the welding part protected against the influence
of the metal and of the air. Mechanically the cover acts as a mould, so that
deformations of the iron which is comparatively soft at the welding temperature
are prevented.
By means of my process the operator is enabled to predetermine the maximum
heat, so that too high a degree of heating of the iron, which perhaps would
cause the melting of the same, is prevented. Further it is an important fact
that in my welding process the source of heat is absolutely free of coal and every
material change of the iron is prevented, so that in spite of the great heat the
chemical continuity of the material remains constant.

page_text: The pressure still can be increased when pieces of sheet metal are introduced
between both surfaces to be welded either before or after they are pressed
against another. The sheet metal advantageously consists of the same material
as the metal to be welded. This sheet metal further serves the purpose to
equalize the welding surface and to create a continuity of the material. In-
stead of sheet metal, a wire net or metal felt can be employed.
In the following I beg to give some examples of apparatus mentioned in the
foregoing description and suitable for executing my process.
In the accompanying drawings:
Figure 1 illustrates an apparatus with clamping jaws' arranged at parts of
both metal pieces.
Figure 1 illustrates a top view of a clamping jaw.
Figure 2 represents a modified construction of a clamping apparatus,
Figure 2 a top view of the modified clamping jaw.
eccentric disc pressing against the
a a are pieces to be welded, b an
material a. The point of rotation of this eccentric disc is at c, and it is supposed
that the points of rotation of all of the different eccentric discs are located upon
€ illustrates the con-
a ring d arranged concentrically to the metal piece a.
necting rod effecting the connection with the corresponding eccentric of the
This connecting rod is
second metal piece a to be welded to the first piece a.
fixed to another point of the eccentric for instance to the centre of the same.
The outer surface of the eccentric disc b is suitably toothed.
From the drawing it can easily be seen, in what manner the apparatus works.
When the metal pieces a expand, the different points tend to move one from
another and an increased tension is placed on the tension rod e put under ten-
sion in a cold state, and the greater the tension, the more the surface of the
eccentric is pressed against the metal piece thereby preventing expansion. This
tension upon the rod e acts as welding pressure at the welding point and effects
the welding itself.
Figure 2 shows a modified construction of the clamping apparatus, in which
the clamping jaws are formed similar to a crank lever. The points of rotation
for the crank lever g are located upon the ring & surrounding the metal piece a.
One leg g of the crank lever lies against the metal piece, whilst the other leg
engages with the tension rod h.
Figure 2 illustrates a top view of the clamping jaw as shown in Figure 2.
The action of the apparatus illustrated in Figure 2 is similar to that illustrated
in Figure 1.
In Figure 3 is illustrated how the tension rods of the clamping jaws may be
r illustrates a coupling through which
elastically connected under tension.
the tension rods z pass. On one end of both tension rods collars s are arranged
to serve as buffer for strong springs t which press against the interior of the
coupling r. This mechanism works in the following manner:
When the clamping jaws connected to the tension rods tend to move from
each other, on the material expanding, owing to the tension of the springs t, the
5 pressure at the welding part increases whilst on the other hand the elastic ten-
sion rods give off as soon as the contraction takes place, after completion of
the welding, in other words as soon as the extremities of the tension rods tend
again to approach each other.
The elastic coupling evidently can be effected in another suitable manner,
0 for instance by rigidly connecting the tension rods with the coupling and by
rendering elastic the coupling itself.

page_text: A New and Improved Process for Welding Metals.
I, Dr. HANS GOLDSCHMIDT, of Essen on the Ruhr, in the Province of West-
phalia, in the German Empire, 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:-
-
The present application relates to a process for welding metal pieces which,
with respect to the processes hitherto employed offers two important differences,
viz.:
1.ly) the welding is effected while the material is in a state of rest,
2ndly) the molecular expansion of the metal itself is employed for effecting
the welding pressure.
With the processes hitherto employed in practice, the metal pieces to be
welded had to effect a certain movement in the moment when they attained
the welding temperature, the welding itself being effected by a blow
or by pressure. Whilst in the old welding processes it was neces-
sary to heat the material and then to bring it into the welding
position, according to my invention just the contrary is done,
namely the pieces to be welded beforehand are adjusted and during the weld-
ing itself remain in the same position. This end is attained in effecting the
initial heating by means of a highly heated mass resulting from the reaction
of aluminum, or aluminum and magnesum, or carbides in combination with
metal compounds, preferably oxygenous compounds (this being the second
essential point of my invention).
In order to execute my process it is in the first place necessary to press in a
cold state the metal pieces to be welded one against the other in such manner,
that a displacement during the heating of the mass is rendered impossible, and
the energy introduced by the heating at the welding place acts as welding
pressure.
The process in this simple form is described hereinafter, the example relating
to the welding of shafts or round bars.
By means of this process it is also possible to weld butt and butt wrought
iron tubes having thin walls and to obtain a much more solid joint than by
flanges, besides the joint obtained by flanges renders the weight of the tube
very heavy and the process much more expensive than that by means of welding
the tubes according to the present invention.
The thoroughly cleaned end surfaces of the work-pieces, for instance shafts,
are pressed one against the other and are surrounded by a suitable mould of
sand or metal in such manner, that the mould being open at its top covers the
whole joint.
A mixture of aluminum and for instance oxide of iron is brought
to reaction in a special crucible. As soon as the reaction is completed and the
contents of the crucible consists of pure iron covering the bottom and a floating
layer of molten alumina, the same is cast upon the joint of the shaft prepared
beforehand. Owing to this heat firstly the welding part attains the welding
temperature and secondly the clamped shaft expands in such manner that a
high molecular pressure is created at the welding part, this pressure effecting
the proper welding.
With my process evidently a certain jolting takes place at the welding part,
the consequence hereof is a contraction of the shafts, in the first place between
the clamps of the clamping apparatus and in the second place of the whole shaft.

page_text: A dangerous consequence of this contraction of the shafts, when the unclamped
part of the shaft is not able to follow, is the breakage of the welded part. This
drawback can be obviated when the clamps surrounding the shaft are loosened
at the moment when the contraction commences, i.e. in the moment when the
shaft commences to cool after the welding is completed. In consequence of the
loosening of the clamps the shaft becomes movable within the clamping
apparatus. The loosening can be effected either by hand or automatically;
in the latter case the clamping apparatus may consist of elastic tension rods in
which springs are set under tension during the expansion of the material, which
springs become discharged again, when the metal contracts. Also in this case
it is supposed that the whole shaft is able to follow the contraction, this would
be the case with a new installation of railway lines, with rails placed upon
broken stones and in most cases where free metal pieces are to be welded.
When the pieces to be welded are fixed to some apparatus or are clamped so
strongly that they cannot effect a contraction, the process must be modified.
In this case it is absolutely necessary that the jolting of the rail and its con-
traction being the natural consequence of the jolting is prevented. This can
be attained in two different manners: either the rails are slightly and without
pressure arranged one against the other and the pressure at the welding part
is produced only when the welding heat itself is attained so that every pres-
sure during the jolting temperature is prevented. The point of welding heat
can easily be ascertained by suitable tests and experiments relating to the pro-
portion of expansion of the rail which clearly and distinctly indicate the time
at which the real welding temperature is attained. In this case the clamping
apparatus is only applied to the rails at the last moment of the welding heat,
i.e. shortly before commencement of the cooling. In this manner the con-
traction of the rail at the welding part is prevented.
Another modification of the process for attaining the same purpose consists
of suitable
in removing the welding surface touching another by means
apparatus to such a distance that owing to the expansion of the rails during
the increased temperature they approach each other to such a degree that only
in the last state of welding heat they touch each other with a certain pressure,
whilst an earlier contact, as long as the rails only are of jolting temperature,
does not take place. When after the completed welding owing to the cooling
and to the contraction of the rail, the same is liberated from the clamps, the
rail adopts its former exact length.
The process described heretofore with respect to the welding processes hitherto
employed offers the following important advantages:
It is possible to press one piece of metal in a cold state against another and
to weld same in the same position. This adjustment is impossible with all other
processes in which after the material has reached the necessary temperature the
welding is effected by means of an ostside pressure or of blows. This is essen-
tially so in the welding of tubes and more especially of tubes having thin walls,
a manipulation which hitherto practically could not be executed at all.
A further advantage must be seen in the fact that the welding part, after
the reaction mass is cast over it, is covered by a layer of alumina which immedi-
ately becomes stiff, whereby the welding part is protected against the influence
of the metal and of the air. Mechanically the cover acts as a mould, so that
deformations of the iron which is comparatively soft in the welding temperature,
are prevented.
By means of my process the operator is enabled to predetermine the maximum
heat by weighing the mass for heating, so that too high a degree of heating of
the iron, which perhaps would cause the melting of the same, is prevented.
Further it is an important fact that in my welding process the source of heat is
absolutely free of coal and every material-change of the iron is prevented, so
that in spite of the great heat the chemical continuity of the material remains
constant.

page_text: The pressure still can be increased when pieces of sheet metal are introduced
between both surfaces to be welded either before or after they are pressed against
another. The sheet metal advantagously consists of the same material as the
metal to be welded, or of material of good welding capacity. This sheet metal
further serves the purpose to equal the welding surface and to create a continuity
of the material. Instead of sheet metal, a wire net or metal felt can be employed.
In the following I beg to give some examples of apparatus mentioned in the
foregoing description and suitable for executing my process.
In the drawings left with the Provisional Specifications similar letters denote
similar parts throughout the different views.
Figure 1 illustrates an apparatus with clamping jaws arranged at parts of
both metal pieces.
Figure 1 illustrates a top view of a clamping jaw.
Figure 2 represents a modified construction of a clamping apparatus,
Figure 2a top view of the modified clamping jaw.
a a are pieces to be welded, b an eccentric disc pressing against the
material a. The point of rotation of this eccentric disc is at c, and it is supposed
that the points of rotation of all of the different eccentric discs are located upon
a ring arranged concentrically to the metal piece a. e illustrates the con-
necting rod effecting the connection with the corresponding eccentric of the
second metal piece a to be welded to the first piece . This connecting rod is
fixed at another point of the eccentric for instance to the centre of the same.
The outer surface of the eccentric disc b is suitably toothed.
From the drawing it can easily be seen, in what manner the apparatus works.
When the metal pieces a expand, the different points tend to move one from
another and an increased tension is placed in the tension rod e put under ten-
sion in a cold state, and the stronger the tension, the more the surface of the
eccentric is pressed against the metal piece thereby preventing expansion. This
tension upon the rod e acts as welding pressure at the welding point and effects
the welding itself.
Figure 2 shows a modified construction of the clamping apparatus, in which
the clamping jaws are formed similar to a crank lever. The points of rotation
for the crank lever are located upon the ring d surrounding the metal-pieces a.
One leg of the crank lever lies against the metal piece, whilst the other leg
engages with the tension rod h.
Figure 2 illustrates a top view of the clamping jaw as shown in Figure 2.
The action of the apparatus illustrated in Figure 2 is similar to that illustrated
in Figure 1.
In Figure 3 is illustrated how the tension rods of the clamping jaws may be
elastically connected under tension. illustrates a coupling through which
the tension rods z pass. On one end of both tension rods collars s are arranged
to serve as buffers for strong springs which presse against the interior of the
coupling r. This mechanism works in the following manner:
When the clamping jaws connected to the tension rods tend to move from
each other, on the material expanding, owing to the springs t, the pressure of
the welding part increases whilst on the other hand the compression of the
springs gradually decreases as long as the contraction of the welding pieces takes
place, after completion of the welding, in other words, as long as the extremities
of the tension rods tend again to approach each other.
The elastic coupling evidently can be effected in another suitable manner,
for instance by rigidly connecting the tension rods with the coupling and by
rendering the coupling itself elastic.
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 —
1. A process for joining or welding metal pieces, in which the two faces to

page_text: be welded are pressed together and the product obtained by the reaction of
aluminum with metal oxide is cast upon the welding spot, said product consisting
of the reduced metal and alumina in a molten and high heated state, so that
the weld is obtained by the molecular expansion of the high heated parts, for
the purpose as described.
2. A process for joining or welding metal pieces, in which the two faces to be
welded get pressed together and the reaction product from aluminum and metal-
oxide is cast upon the welding spot, the product consisting of the reduced metal
and alumina, both being in a molten and high-heated state, whereafter the
working-pieces get pressed under a higher pressure against each other, for the
purpose as described.
3. A process for joining and welding metal pieces, in which the two faces are
fixed in a certain distance to each other and upon the parts to be welded the
heating mass is cast, so that the faces expand under the welding temperature
and press against each other so as to get welded, whereby the welding pieces are
not getting shortened, the whole for the purpose as described.
4. A process for joining and welding metal pieces, in which the faces to be
a wire net of good welding
welded are pressed together after sheet iron or
capacity has been inserted between the same, and in which the heating mass
is cast upon the welding spot, whereafter the welding pieces are pressed against
each other under a higher pressure, for the purpose as described.
Dated this 9th day of June 1900.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.