Advanced Welding Processes: Technologies and Process Control

BS 639
Appendix 2
Shielded metal arc welding (SMAW)
electrode classification
(reproduced by kind permission of
Welding and Metal Fabrication)
The standard identifies electrodes by a series of letters and digits that indicate
the mechanical properties, formulation type and applications. The full electrode
classification consists of a compulsory and optional parts as shown below.
Compulsory
E Electrode for MMA
xx Tensile strength range, minimum yield strength
x First digit for elongation and impact strength
x Second digit indicating temperature for minimum average impact
strength of 47 J
NN Letters indicating coating type
Optional
xxx Three-digit indication of metal recovery
x Welding position
x Current and voltage requirements
H Hydrogen-controlled electrode
This classification is quite complex and it is recommended that the standard
should be consulted for full details. The following notes give an indication of
the typical electrode specifications.
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