JNTUA B.Tech. R20 Regulations

########## JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY ANANTAPUR B.Tech (ME) - IV-I Sem L T P C

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########## (20A03703c) GEOMETRIC DIMENSIONING ANDTOLERANCES (Professional Elective-V) Course Objectives:

- • Teach the basics of the geometric dimensioning and tolerances.
- • Familiar with five groups of GD&T tolerances, form, orientation, location, runout and profile tolerances.
- • Introduce tolerances of profiles of lines and surfaces with or without datums.
- • Expose the students to various surface roughness parameters and their measurements in two dimensions.
- • Understand the concepts of dimensional chains and inspection techniques.

########## Course Outcomes:

- • This course systematically introduces the essentials of the language of geometric dimensioning and tolerancing (GD&T) based on ASME standards, as well as the essentials of surface roughness measurements in both 2D and 3D including filtering techniques.
- • This course also introduces the related concepts of Vectorial dimensioning and tolerancing, dimensional chains, measurement uncertainty, etc.
- • The knowledge gained by the students by learning the above topics will help them to perform very well in their profession as metrologists as well as product designers.

########## UNIT I Basic Concepts

General terms and definitions of geometrical features - General principle of sizes - System of limits and fits - Inspection of dimensional and geometrical deviations - Datums, datum systems, and selection of datums. Restraining degrees of freedom, DOF, Simulators. Rule #1(Boundary principle) and Rule #2.

########## UNIT II Form and Orientation Tolerances

Principles of dimensioning - Introduction to geometric dimensioning and tolerancing (GD&T); Form tolerances: types, specifications and interpretations - measurement and evaluation of straightness, flatness and roundness - Orientation tolerances: types, specifications and interpretations, and verification of orientation tolerances. Exercises on each group. RFS, MMCand LMC concepts.

########## UNIT III Location, Runout and Profile Tolerances

Tolerances of location: types, specifications and interpretations - verification techniques - Tolerances of profiles of lines and surfaces with or without datums - Tolerances of runout - Tolerancing of angles and cones. Exercises on each group. RFS, MMCand LMC concepts.

########## UNIT IV Surface Roughness

Various parameters and their measurements in two dimensions - filtering and filtering techniques - areal parameters, symbology

########## UNIT V Inspection of GD&Tcall-outs

Vectorial dimensioning and tolerancing - Statistical tolerancing of mechanical assemblies - Dimensional chains - Measurement uncertainty - Computer-aided tolerancing and verification. Inspection techniques- conventional and CMM.

########## Textbooks:

- 1. Drake, P. J., Dimensioning and Tolerance Handbook, McGraw-Hill, Inc., New York. 1999.
- 2. Meadows, J. D., Geometric Dimensioning and Tolerancing: Applications and Techniques for use in Design, Manufacturing and Inspection, Marcel Dekker, Inc., New York. 1995.
- 3. Gill, P. S., Geometric Dimensioning and Tolerancing, S. K. Kataria& Sons, New Delhi, 2/e, 2013.
- 4. ASME 14.5 - 2009 standards,
- 5. Alex Krulikowski, Fundamentals of geometric dimensioning and tolerancing, Cengage Learning, 3/e, 2012.
- 6. James D Meadows, -Measurement of Geometric Tolerances in Manufacturing, CRC Press, 1/e, 1998.