Overview - ISO 6848:2015 (Nonconsumable tungsten electrodes)
ISO 6848:2015 specifies requirements for the classification of nonconsumable tungsten electrodes used in inert gas shielded arc welding (TIG/GTAW), and for plasma welding, plasma cutting and thermal spraying. The standard defines how electrodes are identified by chemical composition, marking, sizes, tolerances and quality criteria. Annex A provides informative guidance on conditions of use (e.g., influence of current type).
Keywords: ISO 6848:2015, tungsten electrodes, nonconsumable tungsten electrodes, arc welding, electrode classification
Key topics and technical requirements
- Classification basis: Electrodes are classified by their chemical composition (oxide additives and nominal mass percent).
- Product/process symbol: Gas-shielded tungsten arc processes use the letter W.
- Composition symbols: Chemical symbol(s) for principal oxide additive(s) followed by digits = mass percent × 10 (e.g., WLa15, WCe20). If no additive, symbol is WP; unspecified compositions use WG with explicit additive listing.
- Chemical analysis & retests: Analysis performed on electrode specimens; failed tests are retested twice. Specific retest rules and invalid-test procedures are defined.
- Marking: Electrodes ≥50 mm are marked with colour rings or classification symbols; packaging must be marked for shorter electrodes. Table-based colour codes and examples (e.g., ISO 6848 - WLa15) are provided.
- Sizes and tolerances: Standard electrode diameters and lengths with tolerances are specified; electrodes must pass ring-gage checks for maximum allowable diameter.
- Shape and finish: Straightness limits (e.g., max variation over 100 mm), ground/polished finish, and surface roughness limit (average Ra ≤ 0.8 μm) are defined.
- Rounding and units: Rounding rules reference ISO 80000-1:2009; averaging and unit conversion rules are specified.
- Packaging & traceability: Minimum marking on each package includes ISO number, classification symbol, diameter, length, quantity, supplier ID and lot/heat number.
Keywords integrated: electrode marking, electrode diameters, electrode lengths, electrode finish, chemical composition
Practical applications and users
- Who uses it: Welding consumable manufacturers, suppliers, procurement teams, welding engineers, QA/QC labs, fabricators, and standards/inspection bodies.
- Why it matters: Ensures consistent identification, interchangeability and traceability of tungsten electrodes across welding, plasma cutting and thermal spraying applications. Helps purchasers verify composition, mechanical fit (diameter/length) and surface quality for reliable arc performance.
Related standards
- ISO 80000-1:2009 - Quantities and units (referenced for rounding and unit rules).
- Developed under ISO/TC 44 (Welding and allied processes), SC 3 (Welding consumables).
Use ISO 6848:2015 to standardize procurement, quality control and labeling of nonconsumable tungsten electrodes for safe, repeatable arc and plasma processes.
