It is that branch of welding in which Electric current is used to produce the large heat required for joining together into firm two pieces of metals.
Electrical welding process fall into two main categories
RESISTANCE WELDING.
ARC WELDING.
Comprehensive energy systems.pdf Comprehensive energy systems.pdf
Electric welding
1. 6th Sem
Electrical Engineering Department
Batch – B1 (2014 Batch)
Abhishek Choksi
(140120109005)
Utilization of Electrical Energy & Traction (2160907)
ALA Presentation
On
“Electric Welding”
Prepared By: Guided By:
Prof. Rahish Silavat
Gandhinagar Institute Of Technology
2. Definition of Electric Welding
It is that branch of welding in which Electric current is used to produce the
large heat required for joining together into firm two pieces of metals.
Electrical welding process fall into two main categories
RESISTANCE WELDING.
ARC WELDING.
4. Resistance Welding (RW)
Heat generated by electrical resistance to current
flow at junction to be welded.
Butt welding is a welding technique used to
connect parts which are nearly parallel and don't
overlap. It can be used to run a processing machine
continuously, as opposed to having to restart such
machine with a new supply of metals. Butt-welding
is an economical and reliable way of joining
without using additional components.
Butt Welding (BRW)
5. Spot Welding (SW)
Resistance welding process in which fusion of
faying surfaces of a lap joint is achieved at
one location by opposing electrodes
Used to join sheet metal parts using a series
of spot welds
Widely used in mass production of
automobiles, appliances, metal furniture, and
other products made of sheet metal
Typical car body has ~ 10,000 spot welds
Annual production of automobiles in the
world is measured in tens of millions of
units
6. Seam Welding (SW)
Uses rotating wheel electrodes
to produce a series of
overlapping spot welds along lap
joint.
Can produce air-tight joints
Applications:
Gasoline tanks
automobile mufflers
Various other sheet metal
containers
8. Projection Welding (PW)
A resistance welding process in which coalescence occurs at one or
more small contact points on parts.
Contact points determined by design of parts to be joined
May consist of projections, embossments, or localized intersections of
parts
9. What is an Electric Arc?
An electric arc is a discharge of electric current across a gap in a circuit.
It is sustained by an ionized column of gas (plasma) through which the current flows.
To initiate the arc in AW, electrode is brought into contact with work and then quickly
separated from it by a short distance.
Electric energy from the arc produces
temperatures ~ 10,000 F (55000C),
hot enough to melt any metal
10. Carbon Arc Welding (CAW)
Carbon Arc Welding (CAW) is
a welding process, in which heat is
generated by an electric arc struck between
an carbon electrode and the work piece.
The arc heats and melts the work pieces
edges, forming a joint.
Carbon arc welding is the oldest welding
process.
11. a manual arc welding process that uses a
consumable electrode coated in flux.
An electric current, either alternating current or
direct current, forms electric arc between the
electrode and the metals to be joined.
As the weld is laid, the flux coating of the
electrode disintegrates, providing a shielding gas
and a layer of slag, both of which protect the
weld from contamination until it cools.
Shielded Metal Arc Welding (SMAW)
12. Atomic hydrogen welding (AHW) is an arc welding process that uses an arc
between two metal tungsten electrodes in a shielding atmosphere of
hydrogen.
The electric arc efficiently
breaks up the hydrogen
molecules, which later
recombine with tremendous
release of heat, reaching
temperatures from 3400 to
4000 °C.
Atomic hydrogen welding (AHW)
13. References
• Larry Jeffus’ and Harold Johnson’s Welding Principles and
Applications.
• http://www.esabna.com/EUWeb/AWTC/Lesson1_1.htm
• http://teacher.buet.ac.bd/shabnam/14250_ch3.pdf
• http://ebookbrowse.com/chapter2‐manual‐metal‐arc‐welding‐pdf‐d7
9324541
• http://www.esab.ch/de/de/support/upload/XA00136020‐Submerged
‐Arc‐welding‐ handbook.pdf
• Wikipedia -- https://en.wikipedia.org/wiki/welding