ASME Y14.5

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ASME Y14.5 is a standard published by the American Society of Mechanical Engineers (ASME) to establish rules, symbols, definitions, requirements, defaults, and recommended practices for stating and interpreting Geometric Dimensions and Tolerances (GD&T). [1] ASME/ANSI issued the first version of this Y-series standard in 1973. [2]

Contents

Overview

ASME Y14.5 is a complete definition of Geometric Dimensioning and Tolerancing. It contains 15 sections which cover symbols and datums as well as tolerances of form, orientation, position, profile and runout. [3] It is complemented by ASME Y14.5.1 - Mathematical Definition of Dimensioning and Tolerancing Principles. Together these standards allow for clear and concise detailing of dimensional requirements on a product drawing or electronic drawing package as well as the verification of the requirements on manufactured parts. Effective application of GD&T allows for parts to be verified by dimensional measurements, gauging, or by CMM.

History

The modern standard can trace its roots to the military standard MIL-STD-8 published in 1949. [4] It was revised by MIL-STD-8A in 1953, which introduced the concept of modern GD&T "Rule 1". [5] [6] Further revisions have continued to add new concepts and address new technology like Computer Aided Design and Model-based definition. A list of revisions follows: [6]

ASME Y14.5-2018, "Dimensioning and Tolerancing"
Current Standard
Preceded by ASME Y14.5-2009
ASME Y14.5-2-2017, "Certification of Geometric Dimensioning and Tolerancing Professionals"
Current Standard
Preceded by ASME Y14.5-2-2000
ASME Y14.5-2009
Succeeded by ASME Y14.5-2018
Preceded by ASME Y14.5M-1994
ASME Y14.5M-1994
Succeeded by ASME Y14.5-2009
Reaffirmed in 2004
Preceded by ANSI Y14.5M-1982
ANSI Y14.5M-1982
Preceded by ANSI Y14.5-1973
Reaffirmed in 1988
ANSI Y14.5-1973
Succeeded by ASME Y14.5M-1982
Preceded by USASI Y14.5-1966
USASI Y14.5-1966
Succeeded by ANSI Y14.5-1973
Preceded by ASA Y14.5-1957
ASA Y14.5-1957
Succeeded by USASI Y14.5-1966
Preceded by ASA Z14.1 Series

See also

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References

  1. "Dimensioning and Tolerancing". ASME. Retrieved 5 May 2019.
  2. "SAI Webstore - ANSI Y14.5-1973". Archived from the original on 6 May 2019. Retrieved 5 May 2019.
  3. Dimensioning and Tolerancing - Table of Contents (PDF) (2018 ed.). The American Society of Mechanical Engineers.
  4. Morse, Edward (1 August 2016). "Tolerancing Standards: A Comparison". Quality Magazine. Archived from the original on 11 September 2017.
  5. MacMillan, David M.; Rollande, Krandall (2014). "History of Geometric Methods In Dimensioning and Tolerancing". Circuitous Root. Archived from the original on 25 November 2017. Retrieved 5 May 2019.
  6. 1 2 MacMillan, David M.; Rollande, Krandall (2014). "Bibliography for Dimensioning and Tolerancing With an Emphasis on Geometric Methods". Circuitous Root. Archived from the original on 27 March 2019. Retrieved 5 May 2019.