FIELD OF THE INVENTION
This present invention relates to a high capacity welding wire spool feeding
device in orbital TIG welding machines for tube to tube welding.
BACKGROUND OF THE INVENTION
There are different processes of butt welding of tubes for example, straight tube
butt welding, flash butt welding, induction pressure welding, orbital TIG welding
and manual metal arc welding. One of the welding processes of butt welding of
tubes is the Orbital TIG welding. In this process, the tubes to be welded are
stationary while the welding head carrying the torch revolves around the tube.
The filler wire used comes in a spool. The two ends of the tube which have to be
welded are edge prepared and a fit up is made keeping the correct root gap for
welding. Welding of the joint is done by TIG process. As this orbital TIG welding
machine is portable, compactness, lighter weight, handling simplicity constitute
the adjudging parameters for selection of such machines. The filler wire used
comes in a spool. Diameter of the wire is around 0.6 mm and the weight of the
spool ranges between 175-225 gms. The number of joints that can be welded
with one such spool depends on the outside diameter (OD) of the tube and the
tube thickness. As the volume of the spool is small, only a few tubes can be
welded per spool and frequent changing of the welding spool reduces the
productivity.
OBJECTS OF THE INVENTION
It is therefore the object of the invention is to propose a higher-capacity wire
spool feeding device in orbital TIG welding machines to produce multiple joints
before replacement of the device.
Another object of the invention is to propose a higher-capacity wire spool
feeding device in orbital TIG welding machines to produce multiple joints before
replacement of the device, which substantially increases producing of the
machines.
SUMMARY OF THE INVENTION
Accordingly, there is provided a high capacity welding wire holding device in an
orbital TIG welding machine to multiply the productivity of the machine,
comprising a bracket mounted on the body of the welding machine.
A Spool fixing (flange) roller having a driving pin is mounted on the support
(flange) roller with a nylon washer in between flanges (Spool fixing roller and
support roller) which acts a thrust bearing. The spool fixing roller rotates around
the support roller. A bush is fitted in between Spool fixing roller and support
roller. This assembly is fixed to a bracket by a slotted screw and lock nut. The
slotted screw has a spring with a nylon washer and steel washer at both the
ends of the spring which when compressed by tightening of the slotted screw
exerts a thrust force between the flange of s pool fixing roller and flange of
support roller through the nylon washer. The support roller is prevented from
rotating by a set screw fixed on the bracket. Increasing or decreasing of the
thrust force is achieved by tightening or loosening of the lock nut. The desired
value of thrust force is maintained by a split pin which passes through the hole in
the lock nut and slot in the slotted screw. The welding wire spool is fixed on the
spool fixing roller with the driving pin matching with the hole provided on the
wire spool. The welding wire spool is held in position by a nut. The bracket is
mounted to the machine body.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
The proposed invention will be better understood by the following description
with reference to the accompanying drawing.
Figure 1 - shows a higher-capacity spool feeding device in orbital TIG welding
machines according to the invention.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE
INVENTION
As shown in figure-1, a spool fixing roller (1) having a driving pin (7) is mounted
on a support roller (2) with a first nylon washer (4) interposed between at least
two flanges which acts a thrust bearing. The spool fixing roller (1) rotates around
the support roller (2). A bush (6) is in provided between the spool fixing roller
(1) and the support roller (2). The assembly (1,2,4,6) is fixed to a bracket (3) by
at least one slotted screw (5) and a lock nut (12). The slotted screw (5) has a
spring (8) with a second nylon washer (11) and a steel washer (10) each at both
the ends of the spring (8), which when compressed by tightening of the slotted
screw (5) exerts a thrust force between the flange of the spool fixing roller (1)
and the flange of the support roller (2) through the first nylon washer (4).
The support roller (2) is prevented from rotating by a set screw (14) fixing on
the bracket (3). Increasing or decreasing of the thrust force is achieved by
tightening or loosening of the lock nut (12). The desired value of the thrust force
is maintained by a split pin (13) which passes through the hole in the lock nut
(12) and through the hole in the lock nut (12) and through the slot in the slotted
screw (5). A welding wire spool is fixed on the spool fixing roller (1) with the
driving pin (7) matching with the hole provided on the wire spool. The welding
wire spool is held in position by a nut (9). The bracket (3) is mounted to the of
the orbital TIG-machine.
EXAMPLE
Experiments with the new device establish that tubes of all thickness and all
material specifications, the invented wire spool feeding device performed very
well. About 20% more number of joints could be produced in an one kilogram
welding wire holding device compared to the prior art spool holding device of
equivalent capacity and during corresponding time period.
WE CLAIM
1. A high capacity welding wire holding device in an orbital TIG welding
machine to multiply the productivity of the machine, comprising:
- a bracket mounted on the body of the welding machine;
- a spool-fixing roller having a first flange including a driving pin
mounted on a support roller having a second flange, a first nylon
washer interposed between said first and second flange to act as a
thrust bearing;
- a bush disposed between said fixing and said supporting rollers;
- at least one fastening means having a slotted screw and a lock nut
with a hole, a spring with a second nylon washer, the spring having
one steel washer at each end, the slotted screw upon rotating in a
tightening direction compresses the spring so as to impart a variable
thrust force between said two flanges via the first nylon washer;
- a set screw fixed on the bracket preventing rotation of the supporting
roller,
wherein a desired value of the thrust force is maintained by a split pin
passing through the hole of the lock nut and extending through the
slot of the slotted screw, and wherein a welding wire spool is fixed on
the spool fixing roller through the driving pin having a diameter
corresponding to a hole provided in the wire spool.
2. The device as claimed in claim 1, wherein the welding wire spool is held in
position by a nut.
3. The device as claimed in claim 1, wherein the degree of rotation of the
lock nut increases or decreases the generation of the thrust force.
4. A high capacity welding wire holding device in an orbital TIG welding
machine to multiply the productivity of the machine as substantially
described and illustrated herein with reference to the accompanying
drawings.

The invention relates to a high capacity welding wire holding device in an orbital
TIG welding machine to multiply the productivity of the machine, comprising a
bracket mounted on the body of the welding machine; a spool-fixing roller
having a first flange including a driving pin mounted on a support roller having a
second flange, a first nylon washer interposed between said first and second
flange to act as a thrust bearing; a bush disposed between said fixing and said
supporting rollers; at least one fastening means having a slotted screw and a
lock nut with a hole, a spring with a second nylon washer, the spring having one
steel washer at each end, the slotted screw upon rotating in a tightening
direction compresses the spring so as to impart a variable thrust force between
said two flanges via the first nylon washer; a set screw fixed on the bracket
preventing rotation of the supporting roller, wherein a desired value of the thrust
force is maintained by a split pin passing through the hole of the lock nut and
extending through the slot of the slotted screw, and wherein a welding wire
spool is fixed on the spool fixing roller through the driving pin having a diameter
corresponding to a hole provided in the wire spool.