Overview
ISO 19724:2020 specifies laboratory procedures for the cleanliness assessment of components used in high‑pressure gasoline direct injection systems. The standard defines how to evaluate debris on the “clean” side of fuel injection equipment (high‑pressure pump, injectors, rail, high‑pressure pipe and pressure sensor), because particulate contamination can reduce system performance and lifetime. ISO 19724:2020 is aligned with the measurement and reporting framework of ISO 16232:2018 and adopts the Component Cleanliness Code (CCC) for results reporting.
Key topics and requirements
- Scope and focus: Evaluates contamination originating from manufacturing, assembly and handling of fuel injection components (not in‑service contamination).
- Test environment: Tests must be performed in a clean laboratory; ISO 14644‑1 cleanroom classification class 8 is recommended as a minimum. Weekly blank tests are required to verify test‑bench and laboratory cleanliness.
- Test media and filtration:
- Preferred medium: gasoline test fluid (hydrocarbon similar to gasoline).
- For components not previously in contact with hydrocarbons, deionized water (ISO 3696 Grade 3) with detergent may be used.
- Pre‑filtration ≤ 5 µm; contaminant capture on cellulose filters 5–8 µm.
- Extraction and fluid volume: Use an extraction (declining) curve per ISO 16232:2018 (6.2.3.1 and Annex B) to determine required fluid volume; guidelines for volumes are provided for each component.
- Component‑specific methods:
- High‑pressure pump: Method A (preferred) - operate on a functional test bench under engine‑like conditions (plunger stroke, speed 300–1 500 rpm, outlet pressure 0.5–2 MPa); Method B (alternative) - flushing with pump or syringe.
- Injectors: Operate electrically as on engine; reverse‑flow flushing (nozzle to inlet) with internal filter removed where possible; energising frequency typically 1 000–2 000 min⁻¹, energising time ~90% of cycle. Distinguishes “dry” vs “wet” injectors.
- Rail, high‑pressure pipe, pressure sensor: Defined flushing procedures and minimum fluid quantities (e.g., ≥0.3–1.0 l depending on component).
- Particle analysis & reporting: Particle analysis follows ISO 16232:2018 (Clause 9.2.3). Results are reported using the CCC (Component Cleanliness Code) aligned with ISO 16232 rather than the older FIECC.
Applications and users
ISO 19724:2020 is intended for:
- OEM powertrain and engine quality engineers
- Tier‑1/2 fuel injection component suppliers and manufacturers
- Automotive test and analytical laboratories performing cleanliness verification
- Supplier qualification and incoming inspection of fuel injection equipment
Practical benefits include standardized cleanliness measurement, objective supplier acceptance criteria, reduced risk of injector or pump failures, and improved in‑service performance of gasoline direct injection systems.
Related standards (for reference)
- ISO 16232:2018 - Road vehicles - Cleanliness of components and systems (measurement methods, reporting, CCC)
- ISO 3696 - Water for analytical laboratory use
- ISO 14644‑1 - Cleanrooms and associated controlled environments (air cleanliness)
For safe implementation note: the standard warns about hazardous materials and equipment; users must establish appropriate safety and regulatory practices.