BYNIKHIL ANAND SRIVASTAVA
3rd YEAR - MECHANICAL ENGG.
SEC - J
ROLL NO - 02
Welding is the process of permanently
joining two or more metal parts, by
melting both materials.
The molten materials quickly cool,
and the two metals are permanently
Spot welding and seam welding are
two very popular methods used for
sheet metal parts.
Definition :Metal joining process in which the ends
of pieces to be joined are heated at their interface
by producing coalescence with one or more gas
flames (such as oxygen and acetylene), with or
without the use of a filler metal.
Arc welding is a type of welding that uses a
welding power supply to create an electric
arc between an electrode and the base
material to melt the metals at the welding
Resistance welding involves the generation of heat
by passing current through the resistance caused
by the contact between two or more metal
surfaces. Small pools of molten metal are formed
at the weld area as high current (1000–100,000 A)
is passed through the metal.
In general, resistance welding methods are efficient
and cause little pollution, but their applications are
somewhat limited and the equipment cost can be
Soldering is a process in which two or more metal
items are joined together by melting and flowing a
filler metal (solder) into the joint, the filler metal
having a lower melting point than the workpiece
Brazing is a metaljoining process
whereby a filler
metal is heated
above melting point
between two or more
close-fitting parts by
Welds can be geometrically prepared in many
different ways. The five basic types of weld joints
1. Butt Joint
2. Lap Joint
3. Corner Joint
4. Edge Joint
An image of a cross section of a
welded butt joint, with shading
that shows the locations of the
fusion zone (dark gray) and the
heat-affected zone (middle shade
of gray) in the base material
A welding defect is any flaw that compromises the
usefulness of the finished weldment.
A welding defect mainly weakens the weld joint.
TYPES OF DEFECT
3. Welding angular distortion
4. Welding shrinkage