ISO 10303-519:2000

Overview

ISO 10303-519:2000 - part of the ISO 10303 (STEP) family - defines an application interpreted construct (AIC) for representing geometric tolerances in a computer-interpretable way. The AIC specifies how integrated resources from STEP are interpreted to represent allowable deviations of a product’s shape in accordance with ISO 1101. It provides an EXPRESS schema and entity specializations to encode common geometric tolerance constructs for neutral product data representation and exchange.

Key Topics

• Purpose and scope
  • Interpretation of integrated STEP resources to represent shape tolerances (form, orientation, location, run-out) per ISO 1101.
  • In-scope items include tolerance constraints on shape, tolerance values, datums and datum references, and derived shape elements (e.g., centre lines, intersections).
  • Out-of-scope items explicitly include plus/minus tolerances, presentation on engineering drawings, mathematical definitions of tolerances, inspection methods and tolerance synthesis/analysis.
• EXPRESS schema & entities
  • The AIC provides an EXPRESS short listing (schema: aic_geometric_tolerances) that imports types from STEP integrated resources (measure, shape_aspect_definition, shape_tolerance).
  • Defines subtypes of the generic geometric_tolerance entity for specific tolerance types.
• Enumerated geometric tolerances covered
  • Angularity, circular runout, coaxiality, concentricity, cylindricity, flatness, line & surface profile, parallelism, perpendicularity, position, roundness, straightness, symmetry, total runout, and common datum constructs.
• Assumptions & relationships
  • Intended to be instantiated within application protocol schemas (APs) that implement industrial requirements.
  • References ISO/TS 17450 for shape models (nominal, intermediate/skin model, actual).

Applications and Users

• Primary uses
  • Encoding geometric tolerances in neutral STEP files for CAD/CAM/PLM interoperability.
  • Defining tolerance semantics for product data exchange, archiving, and shared product databases.
• Who uses it
  • Application protocol developers and standards implementers working with STEP.
  • CAD/CAM/PLM system integrators, data exchange engineers, metrology and quality teams who need interoperable tolerance semantics.
  • Organizations implementing automated downstream processes that consume tolerance data (manufacturing planning, inspection software).
• Practical value
  • Enables consistent, machine-readable representation of geometric tolerances across systems, improving interoperability and traceability of design intent.

Related Standards

• ISO 1101 (Geometrical tolerancing)
• ISO 10303 series (STEP): Parts 1, 11, 41, 47, 202
• ISO 5459 (Datums and datum-systems)
• ISO/TS 17450 (GPS model for specification & verification)

Keywords: ISO 10303-519, STEP, geometric tolerances, ISO 1101, application interpreted construct, EXPRESS schema, product data exchange, CAD interoperability, datums, PLM.