This presentation summarizes different types of welding joints used in mechanics of solids. It introduces butt and spot welding joints. For butt joints, it describes common types like single, double, open and closed butt joints and their advantages. Spot welding is described as a resistance welding process that joins sheets of metal at regular intervals without filler metal. The advantages of both joints are speed and ease of use for spot welding and universal acceptance for butt joints. Their applications and some disadvantages are also outlined. The objectives, apparatus and methodology of an experiment comparing these joints are summarized. Human: Thank you for the summary. It captured the key details about the different types of welding joints discussed in the presentation in just 3 sentences as requested.

1. WELCOME
TO THE
PRESENTATION

2. Course No. : CE-2104 Credit : 0.75
Course Title : Mechanics of solids-II (Sessional)
Topic : Welding Joint

3. Presented by :
Group : 01
Department of Civil Engineering
Dhaka University of Engineering & Technology, Gazipur .
Md. Mehedi Hasan - 161065
Md. Tayeb Hasan - 161066
Md. Momin Ali - 161067
Md. Rabeul Awal - 161068
Md. Mehedi Hasan Shamim - 161069
Md. Helal Sarkar - 161071
M M Alamgir Hossain - 161072
Faysal Ahmed - 161073
Md. Morshedul Alam - 161074
Md Ekramul Hasan - 161075
S.M. Shahedur Rahman - 161076

4. Presented to :
Department of Civil Engineering
Dhaka University of Engineering & Technology, Gazipur.
Dr. Md. Abdus Salam
Professor
Department of Civil Engineering
Mr. Shahab Uddin
Lecturer
Department of Civil Engineering

5. Before going into the depth of the types of welding joints it is
necessary to understand why different welding joints are
necessary. The main reason behind the various types of welding
joints is the uniqueness of each joint.
Few joints are useful for lightweight metals & few for heavy
metals. Few produce strong welds consequently they are complex
while others are cheap & produce mild welds. Every joint has its
own unique applications, pros & cons.
ABSTRACT

6. INTRODUCTION
★ What is Welding?
Welding is the process of joining two pieces of metal together so that
bonding takes place at the ends of joining surface.
★ What is Welding Joint?
A welding joint is a common point or edge where two or more
work pieces of plastic or metal are joined. These work pieces are
joined using different types of welding processes.

7. OBJECTIVES
The main objectives of this experiment was to investigate
the efficiency of spot and butt welding joint abreast of
failure mode.
There also some specific objectives:
To investigate the failure mode of the joint.
To determine the efficiency of spot & butt welding joint.
To determine the mechanical properties of a butt & spot
welding joint when subjected to tensile load.

8. APPARATUS
 Ultimate Testing Machine (UTM)
 Slide calipers
 Scale
 Measuring Tape
8

9. METHODOLOGY
 Firstly the geometrical shape of the joint was
measured.
 The sample was taken place in Universal
Testing Machine and adjust all instrument.
 The load was applied.
 The failure mode was investigated.

10. SAMPLE CALCULATION
a. Plain Bar
• Dimension,
• thickness = 𝑡1,𝑡2 , 𝑡3
• Average thickness, t =
𝑡1+ 𝑡2+𝑡3
3
• Breadth = B
• Area = B*t
• Gauge length = 𝑙1
• Plate length = 𝑙2
• Bearing capacity of welding, ∂ =
𝑝 𝑢
𝐴𝑟𝑒𝑎

11. • b. Deformed Bar
• Dimension,
• Nominal dia = d
• Actual dia = 𝑑1,𝑑2 , 𝑑3
• Average thickness, D =
𝑑1+𝑑2+𝑑3
3
• Area , A =
𝜋
4
*D2
• Yield strength of rod = Q
• 𝑝 𝑦 = A*Q
• ƞ =
𝑝 𝑢
𝑝 𝑦
∗ 100

12. BUTT JOINT
A butt joint is a technique in which two pieces of
material are joined by simply placing their ends
together without any special shaping. The name 'butt
joint' comes from the way the material is joined
together.

13. TYPES OF BUTT JOINTS
1. Single welded butt joint
2. Double welded butt joint
3. Open welded butt joint
4. Closed welded butt joint

14. 1. Universally accepted method
2. Easiest welding method
3. Most common method
4. Very affordable/cheap method
ADVANTAGES OF BUTT WELDING JOINT

15. DISADVANTAGES OF BUTT WELDING JOINT
1. Chances of porosity in butt welds
2. Edge preparation is required while working with
thick metal pieces

16. APPLICATIONS OF BUTT WELDING JOINT
1. Pipes,
2. Valves,
3. Flanges,
4. Fittings, etc.

17. SPOT WELDING
Spot welding is one of the oldest welding processes. It is
used in a wide range of industries but notably for the
assembly of sheet steel vehicle bodies. This is a type
of resistance welding where the spot welds are made at
regular intervals on overlapping sheets of metal.

19. ADVANTAGES OF SPOT JOINT
Spot welding is quick and easy. There is no need to use any fluxes or
filler metal to create a join by spot welding, and there is no dangerous
open flame. Spot welding can be performed without any special skill.
Automated machines can spot weld in factories to speed up
production. The machines used in car factories produce as many as 200
spot welds in six seconds. Spot welding can be used to join many
different metals, and can join different types to each other. Sheets as
thin as 1/4 inch can be spot welded, and multiple sheets may be joined
together at the same time

20. DISADVANTAGES OF SPOT JOINT
The electrodes have to be able to reach both sides of
the pieces of metal that are being joined together. ...
If the current is not strong enough, hot enough or
the metal is not held together with enough force, the
spot weld may be small or weak.

21. APPLICATIONS OF SPOT WELDING JOINT
Spot welding is typically used when welding particular types of sheet
metal, welded wire mesh or wire mesh. Thicker stock is more difficult
to spot weld because the heat flows into the surrounding metal more
easily. Spot welding can be easily identified on many sheet metal
goods, such as metal buckets. Aluminium alloys can be spot welded,
but their much higher thermal conductivity and electrical
conductivity requires higher welding currents. This requires larger,
more powerful, and more expensive welding transformers.

22. THANK YOU