Colour codes for tungsten electrodes

Identification code Weight of oxide in % Oxide Colour In the range
WP - - Green

Yes
WT 4 0.35 - 0.55 Th Light blue No
WT 10 0.80 - 1.20 Th Yellow No
WT 20 1.70 - 2.20 Th Red No
WT 30 2.80 - 3.20 Th Purple No
WT 40 3.80 - 4.20 Th Orange No
WZ 3 0.15 - 0.50 Zr Brown No
WZ 8 0.70 - 0.90 Zr White No
WL 10 0.90 - 1.20 La Black On request
WL 15 1.40 - 1.60 La Gold

Yes
WL 20 1.80 - 2.20 La Dark blue

Yes
WC 20 1.80 - 2.20 Ce Grey

Yes
WR 2* Mixed oxides Noble metals Turquoise

Yes
E3® Mixed oxides Noble metals Purple

Yes

*WR 2 not yet standardised

Th: Thorium; Zr: Zirconium; La: Lanthanum oxide; Ce: Ceroxide

Colour codes for tungsten electrodes

 

Overview of tungsten electrode colour coding in PDF format

 

 

WP electrodes:

  • Pure tungsten electrodes
  • AC welding of aluminium alloys
  • Not suitable for DC welding


WT electrodes:

  • Slightly radioactive due to addition of thorium
  • Refrain from using due to increased health risks
  • Improved ignition characteristics and better current carrying capacity compared to WP electrodes


WZ electrodes:

  • Lower risk of contamination of weld thanks to addition of zirconium
  • Tungsten electrodes for AC welding of aluminium alloys
  • Only limited suitability for DC welding


WL electrodes:

  • Increased ignitability thanks to lanthanum oxide
  • Suitable for DC and AC welding
  • Can be used for unalloyed and high-alloy steels; aluminium, titanium, nickel, copper and magnesium alloys; and for microplasma welding
  • Ideal for use in low current range
  • Good substitute for WT electrodes


WC electrodes:

  • Very good ignition and reignition characteristics thanks to ceroxide
  • Suitable for DC and AC welding
  • Can be used for unalloyed and high-alloy steels and aluminium, titanium, nickel, copper and magnesium alloys in the lower and mid current range
  • Good substitute for WT electrodes


WS electrodes:

  • Variable, non-standardised composition
  • Suitable for DC and AC welding
  • Can be used for unalloyed and high-alloy steels and aluminium, titanium, nickel, copper and magnesium alloys in the lower and mid current range
  • Long service life and very durable