Application of TIG & MIG Welding in Manufacturing

1. Presentation on
Applications of TIG and MIG
welding in Manufacturing

2. What is welding?
A fabrication process that joins materials, usually metals,
permanently through localized coalescence to become one.
Coalescence of materials is achieved
by :
 heating them to suitable temperatures
with or without the application of
pressure
 by the application of pressure alone, and
 with or without the use of filler material.

3. TIG welding(Gas Tungsten Arc Welding)
Gas tungsten arc welding is an arc welding process that uses
a non-consumable tungsten electrode and an inert gas for
arc shielding.
It is also known as GTAW.

4. Equipments use in TIG:
 Gas supply (cylinder)
 Electrical power source
(AC/DC)
 Electrode holder, torch or gun
 Connection cables
 Hose (for gas supply)
 Tungsten electrode
 Coolant
 Filler rods

5. Working principle:
 An arc is established between the end of a tungsten electrode and the parent
metal at the joint line..
 A constant-current welding power supply is used to produces energy which is
conducted across the arc through a column of highly ionized gas and metal
vapors known as a plasma.
 Argon and helium are the most commonly used shielding gases.

6. Characteristics of the TIG welding process:
 Uses a non-consumable tungsten electrode during the welding process,
 Uses a number of shielding gases including helium (He) and argon (Ar),
 Is easily applied to thin materials,
 Produces very high-quality, superior welds,
 Welds can be made with or without filler metal,
 Provides precise control of welding variables (i.e. heat),
 Welding yields low distortion,
 Leaves no slag or splatter.

7. QUALITY:
 Gas tungsten arc welding affords
greater control over the weld area
than other welding processes,
 It can produce high-quality welds
when performed by skilled
operators.
 Maximum weld quality is assured
by maintaining cleanliness—all
equipment and materials used
must be free from oil, moisture,
dirt and other impurities, as these
cause weld porosity and
consequently a decrease in weld
strength and quality.

8. Applications:
 TIG is most commonly used to weld thin sections of stainless steel and non-
ferrous metals such as aluminum, magnesium, and copper alloys.
 The aerospace industry is one of the primary users of gas tungsten arc
welding,
 It is also frequently employed to weld small-diameter, thin-wall tubing such as
those used in the bicycle industry.
 TIG is often used in piping of various sizes.

9. TIG in aerospace industry:
 Aerospace industry uses lite metals
(Aluminum and its alloy) thin
sheet and need high quality
welding. So TIG is more suitable
for it.
Fig : Fuel pipes A320 AIRBUS

10. Bicycle industry:
 In Bicycle industry, TIG is
frequently employed to weld
small-diameter and thin-wall
tubing welding.
Fig : TIG in Bicycle industry

11. Others industry:
 Tig welding also used for others
industrial purposes. Such as for
various piping , Joining thin
material in automobile industry.

12. ADVANTAGES AND LIMITATIONS OF TIG
WELDING:
ADVANTAGES:
 No flux is used.
 Welding is smooth and sound with
fewer scatters.
 Very suitable for high quality
welding in thin materials.
 Very good process for welding non-
ferrous metals and stainless steels.
 The surface finish is good.
 The equipments are portable
LIMITATIONS:
 Tungsten inclusion is hard and
brittle.
 Equipment costs are high
 In steel welding operations, TIG is
slower and the most costly one
 Filler rod end, if by chance comes
out, then inert gas shield can cause
weld metal contamination

14. MIG:
 Metal inert gas (MIG) welding also known as MAG and GMAW.
 It is a semi-automatic or automatic arc welding process in which a continuous
and consumable wire electrode and a shielding gas are fed through a welding
gun.
 an electric arc forms between the consumable wire electrode and the workpiece
metal(s), which heats the workpiece metal(s), causing them to melt and join.

15. Equipment and Set up:
1. Cylinder
2. Pressure regulator
3. Pressure gauge
4. Flexible hose
5. Welding gun
6. Power source
7. Welding return lead and clamp
8. Earth connection
9. Shielding gas cylinder
10. Flow meter
11. Wire feed
12. Welding cable assembly
13. Cooling system

16. MIG Welding Process:
 MIG welding is a gas shielded metal arc welding process
using the heat of an electric arc between a continuously
fed, consumable electrode wire and the material to be
welded.
 A wire of copper coated mild steel is fed continuously
from a reel through a gun with a melting rate up to
5m/min.
 Current through the wire ranges from 100 to 400 A
depending upon the diameter of the wire.
 CO2 is principally used apart from argon or argon-helium
mixture as shielding gas.
 The welding machine is a dc constant voltage machine.

17. Applications of MIG
Welding in manufacturing:
Why MIG welding is used in Manufacturing?
 High productivity can lead to higher profits.
 In manufacturing, productivity is the central focus.
 The primary advantage of MIG welding is welding speed.
 It is much quicker than traditional welding.
 High productivity can be achieved in many manufacturing
operations with the use of MIG welding for its clean welds.
 It welds metals quickly.
 It is highly economic.

18. Applications of MIG Welding in
manufacturing: (cont’)
1. Automotive repair.
2. Rebuilding equipment.
3. Overlay of wear resistant coating.
4. welding pipes.
5. It can even be used to reinforce the surface
of a worn out railroad track.

19. 1. Automotive repair
 repairs can be carried out on a number of different vehicles whether they be
large, small, light, or heavy.
 capable of proving a strong weld even down to 0.5mm.

20. 2. Rebuilding equipment:
Rebuilding:-
to repair, especially to dismantle and reassemble with new parts. Example:
to rebuild an old car.
When it comes to fixing broken parts in the field, there are three steps to master:
* Cutting and removal of the failed component.
* Preparation of the new joint/part.
* Welding and cleanup.
worn parts can be repaired by using MIG welding in a variety of coatings (stainless
steel, bronze, nickel, aluminum or hard surfacing) and in a range of hardness, for a
fraction of the cost of purchasing a new part.

21. 3.Overlay of wear resistant
coating:
1. Coatings for Soft Bearing Surfaces
2. Coatings for Hard Bearing Surfaces
3. Coatings for Resistance to Abrasion
4. Coatings for Resistance to Fretting and
Surface Fatigue
5. Coatings for Resistance to Erosion
6. Coatings for Low Friction and Non-stick
Properties

22. 4. weld pipes:
It is more economical to use a track based robotic welding system
than it is to actually man the assembly line.
Special welding equipment will be needed.
Four Reasons to Choose Automated Pipe Welding with Robots:
1. New Technologies
2. Flexibility
3. Weld Quality
4. Productivity

23. 5.To reinforce the surface of a
worn out railroad track:
it can even be used to reinforce the surface of a worn out railroad track.
It can be difficult to join metals of different types, but by choosing the right
filler wire you can actually achieve it over time.

24. Comparison: TIG & MIG
MIG
 Semi automatic or automatic process.
 A consumable bare wire electrode fed
continuously into the weld pool
through torch by spool.
 An inert gas, e.g. argon, has a fluxing
action and creates a protective
shield around the weld pool.
 The feed and flow rate are set by the
operator.
 Does not produce slag.
 Used on sheet metals.
TIG
 Utilizes a non-consumable tungsten
electrode
 An electric arc is formed between a
non-consumable electrode and
the metal being welded.
 An inert gas such as argon creates a
protective gas shield.
 A filler metal is added manually.
 No slag is produced.

25. Safety:
1. Fumes and Gases :
1. Keep your head out of the fumes
2. Use enough ventilation, exhaust at the arc, or both, to keep fumes and gases
from your breathing zone and the general area.
2. Electric Shock :
1. Do not touch the electrode or metal parts of the electrode holder with skin or
wet clothing
2. Keep dry insulation between your body and the metal being welded or ground
3. The coil of wire is ‘electrically hot’ so do not touch it.
REMEMBER: Gas Cylinders require SPECIAL safety precautions
1. Cylinders must be secured in an upright position
2. Cylinders should be located in an area away from arc welding, cutting, heat,
sparks, and flame

26. Conclusion:
 TIG welding needs highly skilled workers to produce high quality weld.
 Maximum weld quality is assured by maintaining cleanliness—all equipment and
materials used must be free from oil, moisture, dirt and other impurities, as
these cause weld porosity and consequently a decrease in weld strength and
quality.
 MIG welding is a huge improvement over some of the previous techniques.
 MIG welding will help contribute to the creation of automobiles, the building of
bridges, and even more importantly, a more efficient way to weld.