Improvements relating to the Welding of Metals by Electricity.
Year: 1890

page_text: COMPLETE SPECIFICATION.
Improvements relating to the Welding of Metals by Electricity.
I, HERBERT ELLSWORTH FOWLER, of New Haven in the County of New Haven and
State of Connecticut, United States of America, Mechanical Engineer, 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 the art of welding metal by the aid of electricity. It is
common to heat metals for the purpose of welding them by the aid of an electric
current and many patents have been taken out and many plans have been tried for
effecting the welding of metals by bringing the parts to be joined, into contact, and
then fusing the metal at the joint by means of an electric current. It has been
proposed to hold the two pieces of metal to be joined in clamps, one or both of which
are movable so as to force the ends of the parts together when heated, and thereby
upset them. It has also been proposed to cause the two parts to overlap at the
point of weld.
One radical defect exists in all methods of electrical welding with which I am
familiar, and this defect may be stated as follows: The two pieces of metal to be joined
being held in alignment by clamps, pressure is exerted upon one or both of the pieces,
and the current being turned on, heats the parts to be joined at a point midway
between the clamps. It has been observed that although the metal may be heated to
a white heat by the current at this point, the parts under treatment may be handled
with the bare hands at a short distance, say six inches from the heated point. If two
pieces of metal be held in the clamps, each piece projecting through one-half the space
between the two clamps, so as to touch, the point of contact will be the point which is
first heated, and which receives the greatest heat. Now according to my observation
and experience, if the joint be worked and then the current is stopped, it will be found
that the weakest part will bo at the joint, and the same principle holds true if the two
parts he moved in the clamp after the weld has been made, so that their junction is at
one side of the centre line between the clamps, in which case the metal would still heat
at this centre line and when the current is turned off, it has been found that the part
thus heated would be weakened at that point. It is evident that, if the above
proposition is true, electrical welding cannot be completely successful when produced
according to the present methods.
I propose to utilize an electric current for the purpose of heating the parts to
be joined and then, after turning off the curront, to maintain them in the heated
condition or further heat them by the use of supplemental external heating means,
until the metal at the joint becomes thoroughly fused. The effect of this supplemental
heating is to destroy the weakening effect of the electric current, to cause the metal
to flow and fuse and to render the parts joined practically homogeneous throughout.
It may be found expedient to work the joint by hammering or rolling, or otherwise,
but the welding performed by my method is not dependent upon such working.
In carrying out my invention I may proceed as follows:
The two parts to be joined are secured in clamps, one of which is movable toward
the other, and the parts having their ends in contact. The parts are then joined by
suitable wires in an electrical circuit, including a source of electricity. The current
expends its force upon the metals to be joined at the point of contact, supposing this
point to be midway between the clamps, and the ends of the parts can thus be heated
to a white heat. When the welding beat has been reached, the supplemental heating
means are brought into action, either before or after the current is turned off. The
means for maintaining or increasing the heat generated by the electric current may
comprise any flame, such as the burning vapor of gas, oil, or the like, and for

page_text: the better directing of the heat upon the work, I prefer to use an air blast which shall
mingle with the products of combustion and direct the flame to the desired point.
During this supplemental heating 1 move one of the clamps so as to upset the ends of
the parts at the point of junction, and, subsequently, I preferably hammer or roll the
work at the point of weld; and this may be done in any of the well known ways.
The clamps may be stationary and the parts may be moved in other ways to upset
their ends.
In the accompanying drawings,
Fig. 1 shows a general plan of the means above mentioned for holding the parts to
be joined and effecting the welding thereof, and comprises a pair of clamps, shown in
side elevation, a storage battery, and wires leading therofrom to the respective clamps,
and a portion of the pipe system for delivering the external heat.
Fig. 2 is an end elevation of one of the clamps and showing means for separating
its jaws, whereby the parts may be removed after the wold is effected; and
Fig. 3 is a section on line 3-3 of Fig. 1 looking in the direction of the arrow.
In the drawings, A, A¹ represent the parts to be welded, which may be two bars,
sheets, rods or tubes of metal. These parts are held respectively in clamps, which
consist of the clamping jaws B, B1, one of which will preferably be movable, so as to
permit of the insertion and removing of the work." These clamps are joined in
an electric circuit by the wires C, C, which are connected to the respectivo poles of a
source of electricity, as for example, the storage battery D. One of the clamps may
be adapted to slide on the base E to upset the parts, and for that purpose the shifting
lever F is shown. G represents the pipe for conveying gas to the burners g, and
H represents a pipe by which a blast of air is directed through the burner, and thereby
causes the flame to impinge directly upon the work.
Suppose now that it be desired to weld the two pieces of metal A, A². They may
be secured as illustrated in Fig. 1 with their ends in contact, whereby the circuit is
closed and an intense heat generated at the junction of the parts. This heat may be
carried to any degree desired, but preferably to a welding heat when the supplemental
heat is brought into action by the ignition of the vapor at the burnors g. The
current may
be turned off simultaneously with the application of the external heat or
immediately before or after such application. The work is then taken up by the
supplemental heat and the metal is maintained at the heat generated by the electric
current, or carried beyond this point, as occasion may require and for such length of
time as will enable the thorough fusing of the parts, and this may be aided by working
the joint as before mentioned. It may be found expedient to carry the heating of the
metals by the electric current alone to a less degree than the welding point and
to supplement this by other heating, or it may be found expedient to carry the
heating by the said current to a point beyond welding and then to remove the parts
from the clamps and subject them, at the point of weld, to the action of heat produced
in any convenient way, or from any fuel.
I do not confine my invention to any particular means for carrying out the method
herein described, and have described only one of the many forms of apparatus
for working. The order of working may also be changed.
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. The method of welding metals by the aid of electricity which consists in holding
the parts to be welded in contact and causing an electric current to traverse the joint,
then cutting off the electric current and applying external heat to complete the
welding.
2. The method of welding metals by the aid of electricity which consists in holding
the parts to be welded in contact and causing an electric current to traverse the joint,
then cutting off the electric current and applying external heat and pressure to
complete the welding.

page_text: 3. The method of welding metals by the aid of electricity which consists in holding
the parts to be welded in contact and causing an electric current to traverse the joint,
then cutting off the electric current and applying external heat and pressure and
working the joint by rollers or hammers to complete the weld.
Dated this 16th day of July 1890.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.