Overview
EN ISO 2160:1998 (ISO 2160:1998) specifies the standardized copper strip test for evaluating the corrosiveness to copper of liquid petroleum products and certain solvents. The method determines how a polished copper strip changes colour after immersion and heating in a test sample under defined time and temperature conditions. The standard covers volatile products (vapour pressure ≤ 124 kPa at 37.8 °C), with special procedures for aviation fuels and natural gasolines that require pressure-vessel testing.
Key topics and technical requirements
- Test principle: Immerse a polished copper strip in 30 mL of sample, heat for a specified time/temperature, then compare the strip colour to corrosion standards.
- Sample handling: Follow ISO 3170 / ISO 3171 sampling; protect samples from light; remove suspended water before testing.
- Apparatus & materials:
- Copper strip: ~75 mm × 12.5 mm, 1.5–3.0 mm thick, >99.9% purity.
- Wash solvent: isooctane (2,2,4‑trimethylpentane) ≥ 99.75% recommended.
- Pressure vessel (for aviation fuels): stainless steel, rated to 700 kPa gauge.
- Test tubes (25 × 150 mm), baths with ±1 °C temperature control, polishing materials and forceps.
- Test conditions:
- Aviation fuels: pressure vessel at 100 °C.
- Natural gasolines: typically at 40 °C (pressure vessel).
- Other products: test tubes at 50 °C, 100 °C or higher depending on product class.
- Preparation & procedure: Precise polishing and handling to avoid fingerprints or water contact; immersion within 1 minute of final polishing; controlled heating and cooling.
- Result interpretation: Classification into corrosion classes 1–4 (from slight tarnish to heavy corrosion/black), with sub‑descriptions (e.g., light orange, claret red, magenta on brassy strip). Report format: “Corrosion copper strip (X h/Y °C), Class Z”.
- Safety notes: Caution for high‑vapour‑pressure samples-do not exceed safe vessel/bath conditions.
Applications and users
- Useful for petroleum testing laboratories, fuel producers, refinery quality control, additive manufacturers, and specification authorities to:
- Verify fuel compatibility with copper/brass components.
- Screen products for corrosive sulfur or other contaminants that affect copper.
- Support fuel specifications and supplier quality agreements.
- Helps manufacturers and end‑users prevent corrosion-related failures in fuel systems, instruments, and storage.
Related standards
- ISO 3170, ISO 3171 - sampling of petroleum liquids.
- ISO 6251 - testing for products with vapour pressure above 124 kPa.
- ISO 5662 - testing of electrical insulating oils (alternative method for those products).
Keywords: EN ISO 2160:1998, ISO 2160, copper strip test, petroleum products, corrosiveness to copper, copper strip corrosion, fuel testing, pressure vessel test.
