Overview
EN ISO 21920-2:2022 - Geometrical product specifications (GPS) - Surface texture: Profile - Part 2 - specifies the terms, definitions and surface texture parameters used when determining surface texture by profile methods. Adopted by CEN from ISO 21920-2:2021 (corrected 2022-06), this standard replaces several earlier profile standards and defines a consistent vocabulary and parameter set for profile-based surface texture measurement.
Key Topics
- Terms and definitions: A unified vocabulary for general, geometrical parameter and feature-related terms used in profile surface texture analysis.
- Field parameters: Categorized parameter types and their intent, including:
- Height parameters: arithmetic mean height, root mean square height, skewness, kurtosis, total height and maximum height per section.
- Spatial parameters: autocorrelation length, dominant spatial wavelength.
- Hybrid parameters: RMS gradient, mean absolute gradient, developed length and developed length ratio.
- Material ratio functions and parameters: material ratio curve, related parameters for stratified surfaces, and volume parameters.
- Feature parameters: Parameters based on peak/pit heights, profile element spacing and heights, peak count and feature characterization.
- Normative procedures and annexes: Guidance on derivatives, local curvature, material ratio curve determination, segmentation (crossing-the-line), feature characterization, and a specification analysis workflow.
- Relation to the GPS matrix: Overviews and mapping of profile and areal standards to the GPS matrix model (Annexes J and K).
- Supersession: Replaces EN ISO 12085, EN ISO 4287, EN ISO 13565-2 and -3.
Applications
EN ISO 21920-2:2022 is used by:
- Metrology and quality engineers writing surface finish specifications and inspection plans.
- Calibration and testing laboratories performing profile measurements and reporting surface texture parameters.
- Manufacturers (automotive, aerospace, tooling, bearings, seals) for process control, acceptance testing and verification of functional surface requirements.
- Standards bodies and technical committees aligning measurement vocabulary across areal and profile methods.
Practical uses include selecting appropriate profile parameters for functional performance assessment, defining measurement and reporting requirements, and ensuring consistent interpretation of surface texture results across suppliers and inspection labs.
Related standards
For specification writers and practitioners, EN ISO 21920-2:2022 provides the authoritative vocabulary and parameter definitions needed to specify, measure and interpret profile surface texture consistently.