Mathematical Definition of Dimensioning and Tolerancing Principles
Engineering Product Definition and RelatedDocumentationPractices
Mathematical Definition of Dimensioning and Tolerancing Principles
Engineering Product Definition and Related Documentation Practices
The next edition of this Standard is scheduled for publication in 2022.
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CONTENTS
Foreword A
Committee Roster . ixCorrespondence With the Y14 Committee .Section 1 Scope and Definitions . 1.1 Scope ...1.2 ASME Y14 Series Conventions . - . 11.3 1.4 References Mathematical Notation . . . 2 21.5 suoua 31.6 1.7 Summary of Conventional Designations . Format . 5 6Section 2 General Tolerancing and Related Principles . 82.1 Surface Points 82.2 2.3 Dimension Origin Features of Size 8 8Section 3 Symbology 13Section 4 4.1 Datum Reference Frames General 14 144.2 Concepts 144.3 Degrees of Freedom . . . - 144.4 4.5 Datum Feature Simulators (Theoretical) . Constraining Degrees of Freedom . 14 154.6 Tabulation of Datum Reference Frames . . 154.7 Candidate Datum Sets and Candidate Reference Frame Sets . .. .. ... Tolerances of Form . . 23 16Section 5 5.1 General . 235.2 Form Control . 235.3 5.4 Form Tolerances Specifying Form Tolerances . . 23 23Section 6 286.1 6.2 Orientation Control . General 28 286.3 Specifying Orientation Tolerances 286.4 Orientation Tolerance 28Section 7 7.1 Tolerances of Location General 33 337.2 Position Tolerancing - - 88
7.3 Projected Tolerance Zone . ... .. . 34
7.4 Conical Tolerance Zone 357.5 Bidirectional Position Tolerancing 367.6 7.7 Position Tolerancing at MMC for Boundaries of Elongated Holes Concentricity and Symmetry . 38 38Section 8 Tolerances of Profile 468.1 General 468.2 8.3 Profile Tolerance Zone Boundaries 46 468.4 Profile Applications 478.5 8.6 Extension of Tolerance Zone Boundaries for Sharp Corners . Nonuniform Tolerance Zone . 48 49Section 9 Tolerances of Runout 629.1 Runout Tolerance 62
Nonmandatory Appendices
A Principal Changes and Improvements . 65B C Mathematical Datum Simulators Referenced at RMB: Definitions and Properties Former Practices 89 79D Concepts Related to Size . 80E A Selection of Mathematical Concepts 82F Potential Misuse of the Swept-Sphere Definition of Size . 85
Figures
1-1 1-2 Example: Cutting Surfaces to Evaluate Circular Runout Example: Distance From a Point to a True Position Axis 61-3 Examples of a Planar Surface of Support 7 62-1 Irregular Features of Size (Type a) Collection of Features . 112-3 2-2 Conformance to Limits of Size Internal Feature of Size . . - Symbols Used in the Definition of Size . 11 112-4 Examples of Surface Atributes Leading to Variations in the Derived Median Line 122-5 The Cutting Plane at a Point on a Local Size Spine and Some of the Evaluation Lines in That Custting Plane . - 122-6 Profile of a Surface Tolerance Describing an External IFOSb 124-1 4-2 Example of Testing Whether a Plane Is a Valid Datum Plane - Example From Table 4-3 - Axis as Primary Datum 21 214-3 Tertiary Datum Feature Simulator Is Basically Located and Oriented 224-4 Example of Translation Modifier 225-1 5-2 Evaluation of Straightness of a Cylindrical Surface Evaluation of Straightness of a Planar Surface 27 275-3 Illustration of Circularity Tolerance Zone for a Cylindrical or Conical Feature 276-1 Planar Orientation Zone With Primary and Secondary Datum Planes Specified . 31 316-2 6-3 Projection of Tolerance Vector Onto Primary Datum Plane - Cylindrical Orientation Zone With Respect to a Primary Datum Plane . 326-4 Linear Orientation Zone Bounded by Parallel Lines 327-1 First Illustration of the Difference Between Surface and Resolved Geometry Interpretations of Position Tolerancing 39
