FIELD OF THE INVENTION
The present invention relates to a method for welding of wire/rod in "T" joint
configuration using Resistance welding process'
BACKGROUND OF THE INVENTION
It is known in the aft that two rods/wires can be joined conventionally by
resistance welding process as lap joints in which a first rod/wire is cross-wise
disposed over a second wire/rod, particularly known as cross wise resistance
welding. This process has the limitations that a rod is extended upwards (after
welding) which are used without edge completion. This kind of joint is also used
in manufacturing of dish drier made of stainless or carbon steel rods and other
applications. This welding practice doesn't give aesthetical approach and leads to
cause some unsafe working and handling conditions while in use'
EP0098852 teaches improvements in or relating to fusion welding methods'
According to this prior aft, resistance to weld toe corrosion, exfoliation corrosion
and stress corrosion of joints welded from metal parent poftions is increased by
a pre-fusion application of a coating, comprised by a metal having a lower
electrochemical potential than the parent metal, to the parent portions'
wo2o0401g13g describes a method for manufacturing a tubular assembly. A
first tube is obtained. A first tubular connector having flrst and second end
poftions is obtained. The first end poftion is metallurgically attached to the flrst
tube. A tubular member having a third end portion is obtained. At least one of
the second and third end portions includes an annular outward fold including
spaced-apart first and second fold poftions. The first tubular connector and the
tubular member are positioned with the second end portion aligned with and contacting the third end poftion. A resistance welding current path is created
through the first tubular connector and the tubular member proximate the
second and third end portions and the second and third end portions are
relatively and deformingly moved together, creating a weld zone which includes
at least some of the second and third end portions. 83EP1745882 describes a method for weld bonding at least two work-pieces
together, and includes applying an adhesive to a first surface of a first workpiece,
and bringing the first suface of the first work-piece into contact with a
suface of a second work-piece. The first work-piece and second work-piece are
then friction stir or friction stir spot welded together, and the adhesive is cured.
The use of bonding tools to maintain the two work-pieces together during curing
of the adhesive is eliminated. OBJECTS OF THE INVENTION
It is therefore an object of this invention is to propose a method for welding of
wire/rod in "T" joint configuration using Resistance welding process.
Another object of this invention is to propose a device to position joinable
wirdrod on a modified top electrode of the welding machine in a method for
welding of wire/rod on the top electrode in a method for welding of wire/rod in
"T" joint configuration.
A stil! another object of this invention is to propose an improved resistance
welding procedure for joining the wires/rods in "T" joint configuration. A fufther object of this invention is to propose a device to positioner joinable
wire/rod on a modified top electrode of the welding machine in a method for
welding of wire/rod, in which the top electrode is designed to hold and release
the wire/rod whenever required.
SUMMARY OF THE INVENTION
In the proposed method, an air compressor based on the pressure requirement
for the weld joint is selected, and a solenoid valve is provided for actuating the
piston inside the cylinder which act as a control unit. According to prior aft, in
the resistance welding process, top and bottom electrode is used. For this
invention, the top electrode is modified so that the wire or rod can be seated in
between machined groove on the top of the electrode, and the tip of the
wire/rod (T joint) which has to be joined is extended further down. The Another
portion of the material to be welded with the top wire/rod is positioned on the
bottom electrode. Welding is done by activating a solenoid valve to open the top
separated electrode for positioning of the wire/rod to be welded by the inventive
device.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1
Figure 2
Shows a schematic of the device according to the invention.
Shows the device clamped to a resistance welding machine. INVENTION
As shown in figure 1 a bottom half (2) of a top electrode (1) is cut in to two
halves and a slot is machined in the cut portions (2, 3) of the electrode (1) to
enable to place a T wire/rod of required diameter. A bottom electrode (4) is
connected to a piston (5) by threaded screw into the end of the piston by
making an internal thread and screwed over the shaft. A self lock nut is
tightened on the thread screw for safety purpose to avoid Backlashing during
tightening. A solenoid valve (5) is actuated by 230 V A/c power supply'
The device is clamped with a resistance welding machine by a metal frame (6) as
shown in Figure 2.
on activating the solenoid valve (5), the piston (5) moves forward and backward
so that the bottom electrode (4) connected the piston (5) gets locked to the top
etectrode (1). The wire/rod (7) to be welded is placed vertically in two machined
stot of the top electrode (1) and when the solenoid (5) is activated the electrode
gets tighten to the other side of the electrode. The other wirelrodlring on which
the top wire/rod to be welded is placed on t he bottom electrode (4). Thus the
resistance spot welding is done with the T joint configuration by set parameters. WE CLAIM :
1. A method for welding of wire/rod in "T" joint configuration using
Resistance welding process, comprising the steps of :
- providing a resistance spot welding machine having at least one solenoid
valve; a piston shaft, and a metal frame;
- modifying the top electrode of the machine;
- providing an external 230V, AC power supply;
- providing an air compressor connected to the power supply for operating
the solenoid valve;
- placing a flrst of two joinable rods/wires on the top electrode;
- placing a second rod/wire on a bottom electrode of the machine;
- activating the solenoid valve to impart a horizontal movement in opposed
directions to enable the bottom electrode including the piston to get
locked with the toP electrode;
- operating the resistance spot welding process to produce a T-joint of said
two rods/wires;
wherein a bottom half of the top electrode is cut in two halves with
construction of a machined slot on each halves, and wherein the first
rod/wire is disposed veftically on the two machined slots.
2. The method as claimed claim 1, wherein, the bottom electrode is connected
to the end of the piston by a threaded screw, and wherein a self-lock nut is
provided on the screwed joint for safe connection.