WELDING THEORY
» Incorrect welding mode.
» Pieces to be welded have different characteristics.
Cold cracks
Cause
» Humidity in the filler metal.
EN
» Particular geometry of the joint to be welded.
9. WELDING THEORY
9.1 Manual Metal Arc welding (MMA)
Preparing the edges
Choosing the electrode
Type of coating
Acid
Basic
Choosing the welding current
Striking and maintaining the arc
Removing the slag
» Carry out the correct sequence of operations for the type of joint to
be welded.
»
Solution
» Always use quality materials and products.
» Keep the filler metal always in perfect condition.
» Pre-heat the workpieces to be welded.
» Carry out post-heating.
» Carry out the correct sequence of operations for the type of joint to
be welded.
Property
70
Use
Carrying out the welding