Fifteen years after initial release of ASME Y14.5M comes the revised edition of Dimensioning and Tolerancing. This 224 page standard is divided into nine sections (see TOC below).
The Y14.5 standard is considered the authoritative guideline for the design language of geometric dimensioning and tolerancing (GD&T.) It establishes uniform practices for stating and interpreting GD&T and related requirements for use on engineering drawings and in related documents.
GD&T is an essential tool for communicating design intent — that parts from technical drawings have the desired form, fit, function and interchangeability. By providing uniformity in drawing specifications and interpretation, GD&T reduces guesswork throughout the manufacturing process — improving quality, lowering costs, and shortening deliveries.
Now, a consensus committee of experts has revised Y14.5 for 21st-century applications. Important changes address: concept of feature of size; datum references and degrees of freedom; composite position tolerances; surface boundaries and axis methods of interpretation; profile tolerances; and symbology and modifiers tools. Additionally, the subject matter has been restructured for better readability, with profile, orientation, and form now in separate sections, and material within sections reorganized.
Ordering information
This standard is available in both printed edition and PDF edition.
Table of contents
Section 1 – Scope, Definitions and General Dimensiong
Section 2 – General Tolerancing and Related Principles
Section 3 – Symbology
Section 4 – Datum Reference Frames
Section 5 – Tolerances of Form
Section 6 – Tolerances of Orientation
Section 7 – Tolerances of Location
Section 8 – Tolerances of Profile
Section 9 – Tolerances of Runout
In addition to these nine sections standard also contains five nonmandatory appendices:
Appendix A – Principal Changes and Improvements
Appendix B – Formulas for Positional Tolerancing
Appendix C – Form, Proportion and Comparison Symbols
Appendix D – Former Practices
Appendix E – Decision Diagrams for Geometric Control
