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[...]... P1: PBU introduction1 MHBD0 31- Cogorno-v6.cls April 8, 2006 17 :58 Source: Geometric Dimensioning and Tolerancing for Mechanical Design Chapter 1 Introduction to Geometric Dimensioning and Tolerancing For many in the manufacturing sector, geometric dimensioning and tolerancing (GD&T) is a new subject During World War II, the United States manufactured and shipped spare parts overseas for the war effort... website P1: PBU introduction1 MHBD0 31- Cogorno-v6.cls April 8, 2006 17 :58 Introduction to Geometric Dimensioning and Tolerancing Introduction to Geometric Dimensioning and Tolerancing 3 When Should GD&T Be Used? Many designers ask under what circumstances they should use GD&T Because GD&T was designed to position size features, the simplest answer is, locate all size features with GD&T controls Designers... Use as given at the website P1: PBU introduction1 MHBD0 31- Cogorno-v6.cls April 8, 2006 17 :58 Introduction to Geometric Dimensioning and Tolerancing 4 Chapter One Ø 3.000-3.030 ±.007 010 2.000 ± 005 010 2.000 ± 005 The traditional plus or minus tolerancing system (The axis of the 3-inch hole must fall inside of the 010 -inch square tolerance zone.) Figure 1- 1 implied, the designer has not indicated which... form, orientation, and location of features on a part Features toleranced with GD&T reflect the actual relationship between mating parts Drawings with properly applied geometric tolerancing provide the best opportunity for uniform interpretation and cost-effective assembly GD&T was created to insure the proper assembly of mating parts, to improve quality, and to reduce cost GD&T is a design tool Before... insure that parts would properly fit and function every time The result was the development of GD&T Ultimately, the USASI Y14.5 19 66 (United States of America Standards Institute—predecessor to the American National Standards Institute) document was produced on the basis of earlier standards and industry practices The following are revisions to the standard: ANSI Y14.5 19 73 (American National Standards... Chapter One Conventional tolerancing methods have been in use since the middle of the 18 00s These methods do a good job of dimensioning and tolerancing size features and are still used in that capacity today, but they do a poor job of locating and orienting size features GD&T is used extensively for locating and orienting size features and for many other tolerancing applications Tolerancing with GD&T... given at the website P1: PBU introduction1 MHBD0 31- Cogorno-v6.cls April 8, 2006 17 :58 Introduction to Geometric Dimensioning and Tolerancing Introduction to Geometric Dimensioning and Tolerancing 5 Ø 3.000-3.030 Ø. 014 @ MMC Cylindrical Tolerance Zone A C 2.000 2.000 B The rectangular tolerance zone is ± 005 in the horizontal and vertical directions Figure 1- 2 A cylindrical tolerance zone compared with... is a design tool Before designers can properly apply geometric tolerancing, they must carefully consider the fit and function of each feature of every part GD&T, in effect, serves as a checklist to remind the designers to consider all aspects of each feature Properly applied geometric tolerancing insures that every part will assemble every time Geometric tolerancing allows the designers to specify the... drafting, manufacturing, and quality professionals This book is also appropriate for a self-study course The material in this book is written in accordance with the latest revision of the geometric dimensioning and tolerancing standard, ASME Y14.5M -19 94 GD&T is a graphic language To facilitate understanding, there is at least one drawing for each concept discussed Drawings in this text are for illustration... Any use is subject to the Terms of Use as given at the website P1: PBU introduction1 MHBD0 31- Cogorno-v6.cls April 8, 2006 17 :58 Introduction to Geometric Dimensioning and Tolerancing 6 Chapter One Size Tolerance Ø 3.000-3.030 Hole Location Tolerance Figure 1- 4 The size, size tolerance, and feature con- trol frame for the hole in Fig 1- 2 The maximum material condition The maximum material condition . Condition 11 2 Boundary Conditions 11 3 Contents vii Zero Positional Tolerance at MMC 11 5 Summary 11 8 Chapter Review 11 9 Problems 12 1 Chapter 8. Position, Location 12 5 Chapter Objectives 12 5 Floating. 16 4 Chapter 10 . Concentricity and Symmetry 16 7 Chapter Objectives 16 7 Concentricity 16 7 Symmetry 17 0 Summary 17 2 Chapter Review 17 3 Problems 17 5 Chapter 11 . Runout 17 7 Chapter Objectives 17 7 Definition 17 7 Circular. P1: PBU introduction1 MHBD0 31- Cogorno-v6.cls April 8, 2006 17 :58 Chapter 1 Introduction to Geometric Dimensioning and Tolerancing For many in the manufacturing sector, geometric dimensioning and