Dimensioning and Tolerancing
American Society of Mechanical Engineers / 27-Mar-2009 / 227 pages
This Standard establishes uniform practices for stating and interpreting dimensioning, tolerancing, and related requirements for use on engineering drawings and in related documents. For a mathematical explanation of many of the principles in this Standard, see ASME Y14.5.1. Practices unique to architectural and civil engineering and welding symbology are not included.
Section 1 establishes definitions, fundamental rules,and practices for general dimensioning. For tolerancing practices, see Sections 2 through 9. Additional information about tolerancing maybe found in Nonmandatory Appendices A through E.
The International System of Units (SI) is featured in this Standard because SI units are expected to supersede United States (U.S.) customary units specified on engineering drawings. Customary units could equally well have been used without prejudice to the principles established.
1.1.3 Reference to This Standard
Where drawings are based on this Standard, this fact shall be noted on the drawings or in a document referenced on the drawings. References to this Standard shall state ASME Y14.5-2009.
The figures in this Standard are intended only as illustrations to aid the user in understanding the principles and methods of dimensioning and tolerancing described in the text. The absence of a figure illustrating the desired application is neither reason to assume inapplicability, nor basis for drawing rejection. In some instances, figures show added detail for emphasis.In other instances, figures are incomplete by intent.Numerical values of dimensions and tolerances are illustrative only. Multiview drawings contained within figures are third angle projection.
NOTE: To assist the users of this Standard, a listing of the paragraph(s) that refer to an illustration appears in the lower righthand corner of each figure. This listing may not be all-inclusive.The absence of a listing is not a reason to assume inapplicability.Some illustrations may diverge from Y14 drawing practices to clarify the meanings of principles.