Overview
ISO/TR 23276:2020 - "Geometrical product specifications (GPS) - Surface texture: Profile method - Flowchart for PSm, RSm, WSm and Pc, Rc, Wc" is a technical report that provides an unambiguous, algorithmic flowchart for computing feature parameters defined in ISO 4287. Its main purpose is to remove ambiguity in software implementations so that results for profile-based surface texture parameters are comparable across instruments and packages.
Key topics
- Scope: Defines a clear algorithmic procedure (flowchart) to calculate mean spacing and mean height of profile elements for primary, roughness and waviness profiles - specifically PSm, RSm, WSm (mean spacing) and Pc, Rc, Wc (mean height).
- Four-part flowchart:
- Part 1 - Detection of all profile peaks and valleys within the evaluation length.
- Part 2 - Peak height discrimination and valley depth discrimination to remove insignificant features.
- Part 3 - Merging adjacent remaining peaks or valleys per defined rules.
- Part 4 - Calculation of profile parameters (generic XSm, Xc), evaluated in both directions across the evaluation length.
- Thresholds and discriminators: Specifies noise-suppression thresholds O (0.01% of Pp/Rp/Wp or Pv/Rv/Wv) and minimum discriminations H (10% of Pp/Rp/Wp for peaks and 10% of Pv/Rv/Wv for valleys) as part of the decision logic.
- Terminology and variables: Uses ISO-aligned terms - profile, evaluation length, profile element, profile peak/valley, spacing, element height - and provides explicit variable definitions for algorithmic implementation.
- Origins: Flowchart extends crossing-the-line segmentation methods (Seewig and Scott) to produce a robust, unambiguous algorithm.
Applications
- Implementation of surface texture analysis in metrology software (ensures reproducible PSm/RSm/WSm and Pc/Rc/Wc values across packages).
- Quality control and acceptance testing in precision manufacturing where profile features (spacing, heights) affect function (sealing, friction, wear).
- Calibration and verification of contact (stylus) instruments and profilometers under ISO 3274 and related GPS practices.
- Research in tribology and surface engineering where consistent feature extraction is required.
Who should use this standard
- Metrologists, software developers for measurement systems, QA/QC engineers, laboratory managers, and standards specialists implementing or validating profile-based surface texture measurements.
Related standards
- ISO 4287 - Terms, definitions and surface texture parameters (primary reference for parameter definitions)
- ISO 3274 - Nominal characteristics of contact (stylus) instruments
- ISO 5807 - Flowchart documentation conventions
Keywords: ISO/TR 23276, surface texture, profile method, PSm, RSm, WSm, Pc, Rc, Wc, ISO 4287, flowchart, profile elements, roughness parameters, metrology.