Updated 05.05.2021
WELDING
with c oated electrode s m.m.a (SMAW)
Manual Metal Arc (also known as shielded metal arc welding) MMA welding is the most common welding process used by domestic users. It requires the use of an electrode holder and a filler metal called "coated electrode". This useful process does not use gas or a wire reel. It is cheaper than other processes and allows the welding of structural steels.
Process principle Gas protection
An electric arc is created between the electrode and the parts to be welded. The parts to be welded and the electrode melt. The weld pool is protected by the gas contained in in the electrode coating.
Weld pool Flux
Weldbead
Core wire
Slag
Welding parts
Applications
Agriculture
DIY
ADVANTAGE S • Easy to carry welding machine • No gas cylinder required • Low cost process • Easy to set up • Welding of most materials
Maintenance
Repair & maintenance
DISADVANTAGE S • Good control of movements is essential • Difficult to clean the weld due to slag
Coated electrode The core wire is the central part of the round wire electrode. usually made of steel, and its role is to conduct he electric current and to melt (filler metal). The different coatings are made up of a complex mixture which gives them their properties (rutile coating, basic coating, etc.).
Core wire diameter
Core wire
Flux
External diameter