What is BS EN ISO 5459:2024 - Geometrical tolerancing. Datums and datum systems about?
An eagerly anticipated revision, BS EN ISO 5459:2024 is a key engineering design standard that gives mechanical engineers the information they need to create and use datums and datum systems in engineering drawings and CAD models.
Who is BS EN ISO 5459:2024 - Geometrical tolerancing. Datums and datum systems for?
- mechanical engineers;
- engineering designers and design engineers;
- independent design consultancies and design agencies;
- manufacturing and production engineers; and
- metrologists and measurement specialists.
What does BS EN ISO 5459:2024 - Geometrical tolerancing. Datums and datum systems cover?
It specifies the terminology, rules and methodology for the indication and understanding of datums and datum systems used by engineering designers/design engineers on their technical product documentation, i.e. engineering drawings and CAD models.
BS EN ISO 5459:2024 also provides explanations to assist the user in understanding the concepts involved, defines the specification operator used to establish a datum or datum system, and provides tools to express location or orientation constraints, or both, for a tolerance.
Why should you use BS EN ISO 5459:2024 - Geometrical tolerancing. Datums and datum systems?
- Universality: BS EN ISO 5459:2024 provides a consistent international language for datums and datums systems used in geometrical tolerancing and product specification, and shapes best practice in design engineering, production specification and production verification.
- Simplification: It offers users a clear and consistent approach to the use of datums and datum systems on technical product documentation. It provides improved tools and methodologies and clarifications of key technical aspects of datum and datum systems, making it easier to use the standard.
- Functionality: It's a tool for optimizing the specification and manufacture of products. It enables the improved fit and function of parts, reduced production costs, better quality, improved product reliability, less scrap, fewer disputes over compliance and faster time-to-market. It also improves understanding of the design intent: the designer's concept.
- Currency: The 2024 version is the latest revision. It introduces new concepts and tools not previously provided. It also plays an important role in supporting the transition away from 2D drawings to a more complete 3D-model-based approach to engineering design as part of the transition to a more digital future.
What has changed?
BS EN ISO 5459:2024 supersedes BS EN ISO 5459:2011. The new version provides improved tools and methodologies for engineering designers to use in their product specifications on engineering drawings and CAD models.
As well, the previous version dealt only with planes, cylinders and spheres being used as datums. As there's a need to consider all the types of surfaces increasingly used in industry, definitions of classes of surfaces are given in an annex to the standard (Annex B). In addition, the following changes have been introduced:
- the normative references (standards cross-referred to) and the references in the Bibliography have been reviewed and updated;
- a number of new definitions have been added; and
- a number of symbols and modifiers have been added, updated and/or clarified throughout the tables and text of the standard.