Working Metals by the Aid of Electricity.
Year: 1889

page_text: Date of Application, 8th Jan., 1889-Accepted, 2nd Mar., 1889
..
otherwise Working Metals by the Aid of Electricity.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents,
Southampton Buildings in the County of Middlesex, 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 :-
My invention relates to apparatus designed especially for use in those welding
operations in which a current of electricity of large volume is caused to pass across
the joint or abutting portions of the parts to be welded for the purpose of bringing
the metal at the point to the welding temperature, preparatory to or simultaneously
with the application of pressure.
My invention relates further to the process of forming welded joints between sections
of pipes or other tubular objects, and also the manner of procedure in forming welded
joints where it is desirable to perfect the weld by hammering.
The first part of my invention consists essentially in the employment of a dynamo
machine or similar generator from which the welding currents are directly or
indirectly derived and which is driven by any suitable motive power such as a
water-wheel, an electric motor, a steam-engine or other device, and in regulating
or governing the current by determining the speed at which the generator shall be
of
agency any suitable
driven by the particular motive power employed, through the
devices placed in proper proximity to the work or controllable by the operator who
manipulates the work. For controlling the power applied to the dynamo and hence,
the speed and electric output of the same, any desired means may be employed.
Some of these means I have described and shown in the accompanying drawings.
By the proper manipulation of the apparatus the power applied to the dynamo
may be thrown on, either quickly or gradually, and thrown off or diminished in

page_text: amount either quickly or gradually so as to control the heating of the object
included in the circuit, and to permit the consumption of power to be entirely cut
off when the work is accomplished.
This part of my invention is applicable likewise to other electric metal working
operations, as forging, shaping, upsetting, soldering, brazing, and the like, in which
an electric current of large velunie, caused to pass through the metal, to be operated
upon or across the joint to be formed is employed as the heating agent for bringing
the work to the proper or desired temperature. I have illustrated this part of my
invention however as applied to apparatus employed in the operation of electric
, welding.
The second part of my invention relates more particularly to the formation of joints
between sections of lead pipe by the electric welding process, though it may likewise
be applied to pipe of other material. The invention consists essentially in forming
the pipes with a taper or chamfer at the part to be abutted and pressing the chamfered
ends together while the joint is traversed by an electric current, and also in the
particular bevel or shape of the taper or chamfer as will be more particularly herein-
after described.
My invention consists further in the process employed in forming an electrically
welded joint finished by hammering, and consists first in removing the pressure by
which the weld is effected and then hammering while a heating electric current is
allowed to traverse the work.
In the accompanying drawings,
Figure 1 is a side elevation and partial section of an apparatus constructed in
accordance with the first part of my invention.
Figures 2, 3, 4 and 5 illustrate other devices which may be employed in the operation
of controlling the driving power or force.
Figure 6 illustrates the form given to sections of pipe to be joined preliminarily to
the welding operation.
Figure 7 shows the same sections as they appear after the welding operation.
Figure 8 shows a pipe in section with its end prepared or shaped in a preferred
manner preparatory to the welding operation.
'
Figure 9 is an end view of said pipe.
Figure 10 illustrates a further slight modification in the shape given to the end of
the pipe.
Figure 11 shows how a T prepared in accordance with my invention may be
inserted between sections of pipe.
Figure 12 shows the T separate.
Figures 13, 14 and 15 illustrate other forms of tube cr pipe prepared in accordance
with my invention Figure. 13 being an elbow, Figure 14 a cap, and Figure 15 a
Ý branch.
Figures 16 and 17 show in side and edge view a fastening section of pipe prepared
in similar manner.
Figure 18 illustrates a prepared cock to be joined electrically to the end of a pipe
or to a T or the like in plumbing.
Figure 19 illustrates a form of holder or clamp that may be used for holding the
pipes or other objects to be electrically welded.
Figure 20 is a diagram illustrating the construction and connections of the dynamo
machine shown in Figure 1.
Referring to Figures 1, 2, 3, 4 5 and 20 C C1, Figure 1 indicate suitable holding
or clamping devices. of good conducting material insulated from one another and
adapted to hold the pieces B B', which are to be welded together.
S indicates a screw or other device by. which one clamp inay be forced towards the
other in the welding operation.
The
The clamps C, are electrically connected by means of suitable brushes borne
by the clamps, with conducting rings R R¹ upon which the brushes rest.
rings RR, are. insulated from one, another and are suitably connected with
c. nductors b, b, upon the armature A of a dynamo machine. This, conductor

page_text: consists of a few turns of heavy wire or of a number of single turns all connected
at their same ends to the same ring as will be well understood by electricians.
The field magnet of the dynamo indicated at M, is supplied with current taken from
a commutator K which in turn is connected by suitable wires indicated at a, a, with
a conductor c, upon the armature A, and preferably independent of that which
supplies the welding or working current to the rings R, R.
The conductor b, is applied to an armature of any desired form, or in any desired
manner, and the alternating currents developed therein pass directly to the work
through the rings, brushes and clamps.
The conductor c, may be wound in the same space with b, on the armature,
under, above or beside the same, or applied in any other way. The alternating
currents developed in it are rectified by the commutator in the well known manner
so as to flow in the same direction as the coils of the field magnet. These
dispositions and connections are diagramatrically shown in Figure 20. The dynamo
itself may be however of any desired construction.
In Figure 1 the dynamo is illustrated as driven by a steam-engine E of any
suitable construction the throttle valve of which, indicated at G is properly located
in proximity to the welding apparatus so that it may be manipulated by the
workman carrying on the welding operation, or is otherwise placed under his
command. P indicates the pipe through which steam is fed to the engine.
The manner of using the apparatus is as follows:-The engine and dynamo
being at rest, the pieces to be welded or otherwise treated are inserted in the
clamps C, C, so as to form the circuit for the current from one clamp to the
other, and the handle G, is turned so as to let in steam to drive the engine E,
and turn the armature shaft of the dynamo. Operating the throttle valve so as to
increase the steam will give an increased volume of current from the dynamo owing
to the increase of speed of rotation thereof, while a decrease of steam will cause the
dynamo to slow down thus decreasing the current according as the operator may wish.
When the desired heat of the piece or pieces has been obtained the steam may be
cut off or gradually diminished for the purpose of gradually cooling the work, or the
valve G may be manipulated in any other desired way to control the rapidily or degree
of heating or cooling of the object in circuit between the clamps. Other devices
controlled and used in a similar manner to the throttle valve are shown in Figures 2,
3, 4 and 5.
In Figure 2 the motive power of any suitable construction is supposed to be applied
to driving a pulley E, which is connected by a loose belt T, with the pulley A upon
the armature shaft. G indicates a belt tightener whereby the belt may be tightened
or loosened to control the power delivered to the pulley upon the armature shaft
and thereby to determine the speed of the dynamo and the current delivered from the
same to the work.
In the arrangement shown in Figure 3, the speed of the dynamo shaft is determined
by means of a lever G, which operates upon a clutch indicated at V, ouo member of
which is operated by the lever while the other member is rotated from the engine E.
The fly wheel of the engine is indicated at W. The clutch V, being a friction clutch
it is obvious that by suitably manipulating the lever G, the power delivered to the
armature shaft may be varied to determine the speed at which the armature shall
revolve and the extent or degree of heating or cooling of the work supplied with
current directly or indirectly from the armature.
In Figure 4 the armature is supposed to be run by a water wheel E, and a gate or
valve G, in the part supplying water to E, serves the purpose of determining the
electric current acting upon the work.
In the modification indicated in Figure 5 the armature of the dynamo machine is
illustrated as driven by an electric motor E, supplied from mains P P. The field
magnet of the electric motor is in one branch of the circuit of the mains P P',
while the armature of the motor is in another branch including a variable resistance
of any suitable character controlled by a switch lever G. By operating the switch
lever it is obvious that the speed of the driving electric motor E, may be varied as

page_text: desired to determine the speed of the dynamo A, and the volume of the current in
the circuit between the clamps C, C¹. The field M of the dynamo may be conveniently
energized from the mains P, P¹
In employing the apparatus described it may be used in any electric welding process
and it will be understood that pressure is applied to the pieces in the clamps by
the devices already described while they are heated by the electric current.
The apparatus described may be used in welding any metal objects together, and
even in the welding of lead or other soft metal pipes.
I find that the best joints between pieces of such pipe are made under specific
conditions, and that by modifying the methods somewhat I am able to join lead
pipe without solder, without increasing the diameter of the pipe, and with a minimum
of labor as compared with the existing methods of making wiped joints.
This part of my invention consists essentially in forming the tube or pipe, or
section of tube or pipe that is to be joined to another section with a taper or chamfer
at the portion to be abutted, as indicated in Figure 6 and following.
The invention consists also in forming the taper or chamfer from the inside outward
and preferably, but by no means necessarily, in such manner that the resultant edge
or ridge shall be somewhat nearer to the interior than to the exterior diameter of
the pipe.
In Figure 6 P P are the pieces of pipe to be joined by clamping them in abutment
and passing a heating electric current through the joint. Dotted lines indicate the
clamps CC, of any construction relatively movable. On the end of each piece of
pipe is made a taper or bevel which includes nearly the whole of the end leaving only
a narrow line or ridge in abutment under comparatively small pressure. On passing
current, the small ridges in contact melt first and as the pieces are moved together,
by the operation of the devices which move the clamp, the tapered portion continues
to melt and solder, as it were, the ends of the pipo together with the material of the
pipe itself giving a result like that shown in Figure 7, a strong and good joint, not
much enlarged.
The tapering of the ends is important for the best results, and to obtain the best
results the tapering should be such as to leave only a narrow ridge of each piece
meeting at the start. This applies to lead and tin pipe chiefly which do not become
weldable properly unless melted at the meeting points. The clamps C C¹, must
follow up the melting as fast as it occurs and keep the solid metal in abutment.
In order to keep the interior of the pipe open and clear the ends are best
prepared as shown in Figures 8, 9 and 10 although this is not absolutely necessary.
Figure 8 shows a double taper both from the bore out and from the outside meeting
in a ridge rather nearer the interior surface of the pipe than its exterior. As
shown in Figure 10 enlarged, a small circular portion of the end may be left flat
at J, J, while the rest is chamfered as shown. I find this mode of preparation of
great value with lead in obtaining good looking joints and without choking the pipe
Bore. The same method is followed in preparing the parts of a T piece to be set
into the pipe by electric welding, as in Figure 12, T being a lead casting (for lead
work) and the lead pipes P, P, and B being joined thereto, as in Figure 11.
I make the T pieces separately by casting and preferably with the ends for joining
tapered for use. They may also be forced into shape in dies as usual with soft
metals.
Elbow pieces Figure 13 are likewise made with tapers for use where it is not
desired to turn a corner by bending the pipe. So also caps of the same metal as
the pipes may be provided for covering or closing a dead end. In Figure 14, such a
cap ready to be welded to a pipe is shown, the end J being tapered by tapering as
shown in Figure 10.
Figure 15 shows a modified T or branch piece Y differing only from piece T
Figure 12 in the direction of the branch connection as regards the pipe itself.
In Figures 16 and 17 the piece F ready to be inserted between the pipe pieces has
ears E E, integral with it for a fastening to a support by nails or screws. It is
needless to say that such piece might also be a branch, or T that the T piece Figure 12

page_text: or elbow Figure 13, or cap Figure 14, or V Figure 15 might each have one or more
such ears for fastening.
Stopcocks may be prepared for use in joining to T branches, to pipes or the like
by the insertion as in Figure 18, of a lead pipe end into a deep groove formed in
the cock M of brass or other metal in which groove a small ring of soft solder S, has
been placed and a suitable flux applied. On heating the cock M to melt the solder,
the piece of lead B, being at the same time forced into the groove in M will perfect
the joint between them and the piece may then, be used to join as in Figure 6 to
other lead pipes or pieces. The piece B Figure 18, it will be seen could have been
a T piece itself, or an elbow I to one end or opening in which the cock M.was affixed
as described.
The invention is not limited to lead and tin pipe merely, but may be applied to
other pipe welding particularly the production as separate manufactures of tees y's
elbows, caps, fastening pieces and the like of such shape as to be readily welded
instead of screwed to the other parts. Non-leaking joints are produced by the above
means without cement, and the joints may be made more rapidly than screw joints
can be cut and put together.
To form a finished weld or joint, I remove the pressure by which the weld is
produced and then hammer, shape or otherwise manipulate the metal pieces as
desired while they are heated or kept hot by a suitable electric current passing through
them.
By the removal of the pressure the further approach of the pieces is prevented
during the final working. The beating current for the final operation may be less
than that required to produce the welding temperature. This part of my invention
applies especially to the union of iron, steel or other hard metal pieces.
Instead of simply removing the pressure a force may be applied which will tend to
separate the pieces.
If this force is not too great it will facilitate the final work by allowing spreading
of the metal while heated by an electric current passing through it.
The operation may be employed with the apparatus already described or by use of
the holding clamps shown in Figure 19 of the drawings.
The current may be graduated or regulated by varying the driving power and
consequent sped of the dynamo by any of the means shown in Figures 1 to 5 of the
drawings. The current might be graduated for the purpose of this part of my
invention by varying the magnetic field of the dynaino machine which gives the
current energy, or by varying the resistance interposed in the circuit of the welding
currents, or by varying the resistance, or the inductive resistance in either the primary
or secondary of the induction coil or converter when the converter is used for
developing the welding current of large volume, or by varying the reaction or self
induction of the armature or welding circuit, when alternating currents derived
directly from a dynamo machine are employed, or by varying the inductive relation of
the primary and secondary of the converter through changes in their relative
position or in the mass or position of the mass of iron of the converter; or by
varying the position of the commutator of the dynamo, or by any other desired
means.
In Figure 19 of the drawings two ordinary holding clamps are shown, but one of
them is provided with a handle H, by which pressure may be applied tending to force
the piece held by the clamp towards or away from the piece held by the other
clamp.
The two pieces to be united having been placed in the clamps and united by
pressure applied while they are heated by the current, the pressure is removed, and
the pieces being still connected to the welding circuit the adjusting or regulating
appliances are manipulated so as to cause a current of sufficient volume to How for
keeping the pieces hot.
While so heated they are subjected to the desired hammering, shaping or other
operation.

page_text: It is sometimes preferable to apply force by means of the handle S, in a direction
to tend to separate the pieces during the hammering or other operation.
Although I prefer to perform the final operation while the pieces are still heated by
the current used in welding I do not limit myself to so doing, since it is obvious that
the pieces might be allowed to cool and be afterwards again heated and then hammered.
The degree of heat employed in the hammering or finishing operation is obviously a
matter of choice with the operator.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed as communicated to me
by my foreign correspondent I declare that what I claim is :-
First In an apparatus for electric welding, forging, brazing or other metal working
operations in which an electric current is employed to heat the metal under treatment,
a dynamo machine supplying the heating current to the clamps or holders for the work,
and suitable means placed in proximity to the part of the apparatus in which the
work is carried and under the control of the operator, for varying the driving
power of the dynamo so as to apply, cut off or vary the heating current in the work
at will.
Second The herein described improvement in forming electrically welded joints
between pipes, tubes or tubular pieces consisting in forming a taper or chamfer upon
the end of the tube or tubular portion, abutting the end of the tube against the tube
or pipe to which it is to be joined, and subjecting the two pieces or sections of pipe
to an endwise pressure while they are in a heated state, as and for the purpose
described.
Third The herein described improvement in electrically welding pipes, tubes, or
tubular pieces or objects consisting in forming a double taper or chamfer both from
the bore out, and from the outside inward, as and for the purpose described.
Fourth The herein described improvement in electrically welding pipes, tubes or
tubular pieces, consisting in chamfering or tapering the tubular end so as to leave a
narrow ridge or edge rather nearer the inside than the outside diameter of the tube,
as and for the purpose described.
Fifth The herein described improvement in welding together two tubular sections
or pieces of lead, tin, or other soft metal consisting in forming the abutting ends of
the tubes or tubular portions with a narrow edge or ridge, passing a heating electric
current across the joint and moving the pieces together to follow the melting of the
tapered portion.
Sixth Tie herein described method of finishing an electric weld consisting in
removing the pressure by which the weld is effected, and then hammering or
shaping or otherwise working the pieces while they are traversed by a heating electric
current.
Seventh The herein described method of finishing an electrically welded joint
consisting in simultaneously applying a heating electric current, and a force
tending to separate the joint while subjecting the joint to the hammering or other
operation.
Dated this 8th day of Ionuar 1880
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,
Agents for the Applicant.