The document provides an overview of welding as a workshop topic, including definitions, common terms, types of welding, materials and tools used, applications, advantages and disadvantages. It discusses arc welding and gas welding processes. The objectives of welding are to join two metal pieces together to form a singular piece that cannot break apart under load. Safety is emphasized as an important part of the welding workshop.

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Technical College of Engineering
Petrochemical Department 2nd
(WORKSHOP & INDUSTIRAL SAFTEY )
Prepared by: Lecturer :
AMAR ASKANDAR Mr. Lazgeen
Name of Workshop : “ WELDING ”
SECOND Class 2019 - 2020

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TABLE CONTENT
No. TOPIC
1. INTRODUCTION
2. COMMON TERMS
3. PURPOSE
4. TYPE OF WELDING
5. MATERIAL AND TOOLS
6. APPLICATIONS OF WELDING
7. ADVANTGES & DISADVANTGE OF WELDING
8. PRUSEDURE
9. CONCLUTION
10. REFFRENCE

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INTRODUCTION
Welding is a common process for joining metals using a large
variety of applications. Welding occurs in several locations, from
outdoors settings on rural farms and construction sites to inside
locations, such as factories and job shops. Welding processes are fairly
simple to understand, and basic techniques can be learned quickly.
Welding is the joining of metals at a molecular level. A weld is a
homogeneous bond between two or more pieces of metal, where the
strength of the welded joint exceeds the strength of the base pieces of
metal.
At the simplest level, welding involves the use of four components: the
metals, a heat source, filler metal, and some kind of shield from the air.
The metals are heated to their melting point while being shielded from
the air, and then a filler metal is added to the heated area to produce a
single piece of metal. It can be performed with or without filler metal
and with or without pressure.
There are several types of welding that are used today. Gas Metal Arc
Welding (GMAW) or MIG, Gas Tungsten Arc Welding (GTAW) or
TIG, Flux Core Arc Welding, and Stick Welding are the most common
found types in industrial environments. [ 1 ]

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COMMON TERMS
There is a large vocabulary of specific welding terms. Knowing these
terms is essential to learning about welding as well as understanding
how to weld.
Arc Burn : Arc burn is a metallurgical notch caused by ground clamps
or striking an arc on the base metal at any point other than the weld
groove or immediate area that will be covered with the weld cap.
Base Metal: The base metal is the metal that is to be welded or cut. It
is commonly referred to as the workpiece.
Butt Weld :A butt weld is a joint between two workpieces that are
aligned on the same plane.
Cover Pass: The cover pass finishes the welded joint. It is higher than
the adjacent surface and overlaps the groove.
Filler Pass: The filler pass follows the hot pass and fills the weld groove
flush, or almost flush, with the surface of the workpieces.
Fillet Weld: A fillet weld is the joining of two workpieces with
triangular cross-sections at approximately 90 degrees.
Heat-Affected Zone: The heat-affected zone is the area of metal near
the weld metal that was not melted during welding, but did experience
changes in its mechanical properties and/or microstructure due to the
heat applied.
Hot Pass: The hot pass is the pass immediately following the stringer
pass.
Joint: The hot pass is the pass immediately following the stringerpass.
Plug Weld: Plug welding is filling a hole or gap in one piece with weld
or filling a hole and attaching the piece with the hole to the surface of
another base piece.
Polarity: Polarity is the manner in which the electrode holder and
workpiece connect to the electrical supply. This can be either direct
current electrode negative, or DCEN, meaning straight polarity or
direct current electrode positive, or DCEP, meaning reverse polarity.
Spot Weld: Spot welding is the process in which the weld pieces are
pressed together with pressure, then a current is passed through them
in a small spot and the two pieces are melted together at that location.
Spot welding can be performed on metals from 0.5 to 3 mm.

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Welding Electrode :In arc welding, the electrode is used to pass current
through the workpiece to fuse the two pieces together.
PURPOSE
Welding is a fabrication or sculptural process that joins materials,
usually metals or thermoplastics, by causing fusion, which is distinct
from lower temperature metal-joining techniques such
as brazing and soldering, which do not melt the base metal. “
I guess that isn’t an objective, rather a definition.
The objective of welding is to join two separate pieces of metal or
plastic together to form one singular piece… and not be able to break
apart under (potential) applied load.
 To improve the penetration of welding joint .
 To know main function of welding.
 To know the part of welding gas and arc.
 To ensure student know the prevention of accident.
 To ensure student know the skills of welding.
 To know what is a true step when doing a welding.
 To ensure all student according to the instruction and safety
 To minimize number of passes of weld and hence increase
productivity.
 To find out the best type of activated flux which can give the
better performance for this process .

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TYPE OFWELDING
There are many typed of welding with many different
techniques in our workshop we tried to explain the most
important and most simple type of them.

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Arc Welding:
Arc welding is one of several fusion processes for joining metals. By
applying intense heat, metal at the joint between two parts is caused to
intermix – directly, or more commonly, with an intermediate molten
filler metal. Upon cooling and solidification, a metallurgical bond is
created. Since the joining is an intermixture of metals, the final well-
meant potentially has the same strength properties as the metal of the
parts. This is in sharp contrast to non - fusion processes of joining (i.e.
soldering, brazing etc.) in which the mechanical and physical properties
of the base of be duplicated at the joint.

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MATERIAL AND TOOLS
Arc Mechine Electrod
Head Shield Wire Brush

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APPLICATIONS OF WELDING
The welding is widely used for fabrication of pressure vessels,
bridges, building structures, aircraft and space crafts, railway coaches
and general applications besides shipbuilding, automobile, electrical,
electronic and defense industries, laying of pipe lines and railway
tracks and nuclear installations. Specific components need welding
for fabrication includes:
(a) Transport tankers for transporting oil, water, milk etc.
(b) Welding of tubes and pipes, chains, LPG cylinders and other items.
(c) Fabrication of Steel furniture, gates, doors and door frames, and
body
(d) Manufacturing white goods such as refrigerators, washing
machines,microwave ovens and many other items of general
applications
Advantages of welding are enlisted below:
1. Permanent joint is produced, which becomes an integral part of work
piece.
2. Joints can be stronger than the base metal if good quality filler
metal is used.
3. Economical method of joining.
4. It is not restricted to the factory environment.
Disadvantages of welding are enlisted also below:
1. Labor cost is high as only skilled welder can produce sound and
quality weld joint.
2. It produces a permanent joint which in turn creates the problem in
dissembling if of sub-component required.
3. Hazardous fumes and vapors are generated during welding. This
demands proper ventilation of welding area.
4. Weld joint itself is considered as a discontinuity owing to variation
in its structure, composition and mechanical properties; therefore
welding is not commonly recommended for critical application where
there is a danger of life.

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LABORATORY WORK PROCERDUR
Welding Arc.
1.Prepare a piece of mild steel plate .
2.Use an electrode
3.Adjust the ampere
4.Put an electrode at the electrode holder and make sure that there are
no movement of electrode at the holder.
5.Hold that position over a spot just inside the left edge of the base
metal until a molten pool is established.
6.Welding then proceeds from left to right(for the right hand)
7.Stop the process at the end of the work piece.
8.The correct technique is hold an electrode at the start position for 1s
or 2s and continue until the end of the process. At the end, hold an
electrode at the last position for 1s or 2s before finishing the process.
9.The frequency of this action will be determined by the size
of the weld being deposited, and the correct action improve
with practice.

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AMAR
CONCLUSION
In this workshop we learned what welding, what types of
welding, how to weld in the workshop and how to prevent in
the workshop before starting the welding process At these
practical, we learn about how to joining the plat iron use the
Arc and Gas Welding. Other than that we also have been teach
by our lecturer how to adjust the volume of the electric. Besides
that ,Our teacher always remain us to stay alert in safety while
doing a work before and after finish the practice. Conclusion
is, I want to thanks to lecturer and my friend during learning of
arc and gas welding. How ever,these practical i will never ever
forget because these talent is bring us to learn a new thing’s in
my studying at these school.

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REFRENCES
1. https://www.techtransfer.com/blog/introduction-to-welding/
2. https://www.quora.com/What-are-some-objectives-of-
weldinghttps://www.quora.com/What-are-some-objectives-of-
welding
3. http://www .ask.com/search?=welding+gas+arc
workshop&oq=welding+gas.
4. .http://www. Google.com=welding+gas=arc&oq welding.