The document provides information about welding from a presentation given by Surendra Kumar. It discusses different types of welding including gas welding, arc welding, and their advantages and limitations. Gas welding uses oxygen and acetylene to produce a flame and includes oxy-acetylene welding. Arc welding uses an electric arc between an electrode and base metal to produce heat. Common applications of welding include automobile, aircraft, machinery manufacturing and structural/ship building. In conclusion, welding is widely used in industries to join metals and provides design flexibility at a relatively low cost.
3. SIMPLEX CASTING Ltd
UNIT-III
223/2,224 TEDESARA,INDUSTURIAL,MUDIPAR ROAD
INTRODUCTION
It is a fabrication department of simplex or
deportment of production. Internal planning for
sequence of manufacturing of the job. Then cutting
and fitting and welding then finishing
5. Welding:
The Welding is a process of joining two or more,
similar or dissimilar metals by heating them to a
suitable temperature , with or without the
application of pressure, filler materials and flux.
Welding is used for making permanent
joints.
6. TYPES OF WELDING :
Plastic Welding or Pressure Welding:
The piece of metal to be joined are heated to a plastic
state and forced together by external pressure
(Ex) -Resistance welding
Fusion Welding or Non-Pressure Welding:
The material at the joint is heated to a molten state and
allowed to solidify
(Ex)- Gas welding, Arc welding
7. CLASSIFICATION OF WELDING PROCESSES:
Gas welding(Oxy- Acetylene)
Arc welding(Metal Arc)
Resistance welding
Solid state welding
Thermo-chemical welding
Low Temperature welding
8. Gas Welding:
Gas Welding is a fusion welding process, in which the
heat for welding is obtained by the combustion of
oxygen and fuel the gas may be acetylene ,hydrogen or
propene .
Types:
• Oxy- Acetylene
• Air-Acetylene
• Oxy-Hydrogen
• Oxy-Fuel
9. Oxy-Acetylene Welding:
When a combination of
Oxygen and acetylene is
used in correct
proportions to produce an
Intense gas flame, the
process is known as
oxy-acetylene welding.
10. Gas Welding Equipment :
1. Gas Cylinders
Pressure-
Oxygen – 125 kg/cm2
Acetylene – 16 kg/cm2
2. Regulators
• Working pressure of oxygen 1 kg/cm2
• Working pressure of acetylene 0.15 kg/cm2
• Working pressure varies depends upon the thickness of the work pieces
welded.
3. Pressure Gauges
4. Hoses
5. Welding torch
6. Check valve
7. Non return valve
11. Advantages:
Portable and most versatile process.
Better control over the temperature.
Suitable to weld dissimilar matter.
Low cost & maintenance.
Disadvantages:
Not suitable for heavy section.
Less working temperature of gas flame.
Slow rate of heating.
12. Arc Welding:
“Arc welding is a fusion welding process in which the
heat required to fuse the metal is obtain from the
electric arc between the base metal and an electrode.
Types:
1. Metal Arc Welding
2. Submerged Arc Welding
3. Tungsten Inert Gas Welding
4. Metal Inert Gas Welding
13. Equipment:
A welding generator (D.C.) or Transformer (A.C.)
Two cables- one for work and one for electrode
Electrode holder
Electrode
Protective shield
Gloves
Wire brush
Chipping hammer
Goggles
14. Metal Arc Welding :
Uses an electric arc to
coalesce metals
Arc welding is the most
common method of
welding metals
Electricity travels from
electrode to base metal
to ground
15. Advantages and Disadvantages of Arc Welding
Advantages
Most efficient way to join
metals
Lowest-cost joining
method
Affords lighter weight
through better utilization
of materials
Joins all commercial
metals
Provides design flexibility
Disadvantages
Manually applied,
therefore high labor cost.
Need high energy causing
danger
Not convenient for
disassembly.
Defects are hard to detect
at joints.
16. Applications:
It is used in the manufacture of automobile
bodies.
Aircraft Frames
Railway Wagons
Machine Frames
Structural works, tanks, furniture, boilers,
general repair work and ship building etc.
17. Conclusion:
In these we learn about most popular welding
type uses in industries.
A good weld is always strong.
General welding equipment is not very costly.
Portable welding equipment are available.
A large number of metal and alloy both similar and
dissimilar can be join by welding.
Welding permits considerable freedom in design.