Overview
ISO 2401:2018 - "Welding consumables - Covered electrodes - Determination of the efficiency, metal recovery and deposition coefficient" specifies standardized test methods to quantify how much usable weld metal is produced from covered electrodes. The standard defines procedures to measure electrode efficiency, weld metal recovery, deposition efficiency and the deposition coefficient for covered electrodes used in arc welding. ISO 2401 is intended for consistent, repeatable laboratory measurement of welding consumables’ performance.
Key topics and requirements
- Test specimens and preparation
- One carbon-steel test plate per electrode diameter (approx. 75 × 300 × 12 mm); cleaning and pre-weighing to ±1 g.
- Number of electrodes
- Tests use 3, 5 or 8 electrodes depending on deposit mass (3 permitted if each deposit >100 g).
- Weighing and measurement accuracy
- Electrode and plate masses to ±1 g; core wire lengths to ±1 mm; arcing time to ±1 s.
- Welding parameters
- Welding current set at about 90% of the electrode’s maximum flat-position range; polarity and current type (AC or DC +/−) per manufacturer recommendation. Arc length and welding technique must be typical for the electrode.
- Stub ends and limits
- Electrodes used until ~50 mm stub remains; total stub-end length requirements specified by electrode count (e.g., ~144–156 mm for three electrodes).
- Calculations and formulas
- Nominal and effective electrode efficiency: ratio of weld metal mass deposited to core-wire mass consumed (×100%).
- Overall weld metal recovery and deposition efficiency: definitions and formulae provided.
- Deposition coefficient (g·A−1·min−1): mass deposited divided by (current × arcing time). Final values rounded as specified.
- Rounding and units
- Rounding and unit conventions follow ISO 80000-1:2009. Results must be suffixed with current type (e.g., R_N+, R_E~, etc.).
Practical applications and users
- Manufacturers of welding consumables use ISO 2401 to characterize and publish electrode performance data.
- Welding engineers and R&D teams apply the standard during product development and quality control.
- Test laboratories and certification bodies use the methods to verify compliance, perform comparisons across batches, and support procurement specifications.
- Useful for welding procedure qualification, cost-per-deposited-metal assessments, and selecting electrodes for productivity-sensitive applications.
Related standards
- ISO 80000-1:2009 - Quantities and units (used for rounding and unit conventions).
- Developed by ISO/TC 44/SC 3 (Welding consumables); see related ISO/TC 44 documents for complementary welding-consumable test methods.
Keywords: ISO 2401, covered electrodes, electrode efficiency, metal recovery, deposition coefficient, welding consumables, deposition efficiency, weld metal recovery, welding test procedure.