GUJARAT TECHNOLOGICAL UNIVERSITY

DESIGN FOR MANUFACTURING AND ASSEMBLY

Type of course: Post Graduate

Prerequisite: Zeal to learn the Subject

Rationale: To introduce the basic concepts and design guidelines of different manufacturing processes.
It is also equally important to understand conceptsof design for assembly to reduce number of parts and to
optimize design without compromising function. Also, current global trends and requirements of
environmental design required to be addressed.

Teaching and Examination Scheme:

Teaching Scheme Credits Examination Marks Total

Content:
Sr. Content Total
% Weightage
No. Hrs
1 Introduction to tolerances:
Tolerances: Limits and Fits, tolerance Chains and identification of
functionally important dimensions.Dimensional chain analysis-equivalent
tolerances method, equivalent standard tolerance grade method,equivalent
influence method. Geometric tolerances: applications, geometric tolerancing 7 18%
for manufacture as per Indian Standards and ASME Y 14.5 standard;
surface finish, Tolerance stackup calculations; Review of relationship
between attainable tolerance grades and different machining.
2 Form design of castings, weldments, forging and sheet metal
components:
Materials choice, Influences of materials,Space factor,Size, Weight- Surface
properties and production method on form design. Redesign of castings 9 21%
based on parting line considerations, Minimizing core requirements,
redesigning cast members using Weldments-Form design aspects in
Forging and sheet metal components.
3 Design for Assembly - Machining Considerations:
Design features to facilitate machining, Drills, Milling cutters, Keyways,
Doweling procedures, Counter sunk screws, Reduction of machined area,
Simplification by separation, Simplification by amalgamation,Design for
machinability, Design for economy, Design for clampability, Design for 9 21%
accessibility, Design for assembly. Redesign For Manufacture, Design
features to facilitate machining: datum features, functional and
manufacturing.Component design, machining considerations, redesign for
manufacture.
 4 DFMA Tools:
Rules and methodologies used to design components for manual, automatic
and flexible assembly, traditional design and manufacture Vs concurrent
engineering, DFA index, poke -yoke, lean principles, six sigma concepts,
DFMA as the tool for concurrent engineering, three DFMA criteria for 9 21%
retaining components for redesign of a product; design for manual assembly;
design for automatic assembly- Computer-aided design for assembly using
software.
5 Design for the Environment:
Introduction, Environmental objectives, Global issues,Regional and local
issues, Basic DFE methods, Design guide lines, Weighted sum assessment
method,Lifecycle assessment method,Techniques to reduce environmental 8 19%
impact, Design to minimize material usage,Design for disassembly, Design
for Recyclability, Design for remanufacture, Design for energy efficiency,
Design to regulations and standards.

Reference Books:
1. Product Design for Manufacture and Assembly, G. Boothroyd, P. Dewhurst, W. A. Knight, CRC
Press.
2. Assembly Automation and Product Design, G. Boothroyd, CRC Press.
3. Product Design and Development,K. T. Ulrich and S. D. Eppinger, McGraw-Hill Higher Education
4. Handbook of Product Design for Manufacturing, Bralla, James G., McGraw Hill.
5. Engineering Design - A Material Processing Approach, G E Dieter, McGraw Hill
6. Mechanical Tolerance stackup and analysis, B. R. Fischer, CRC Press.
7. Mechanical assemblies: their design, manufacture, and role in product development, D E
WhitneyOxford Press.

Course Outcome:
After learning the course the students should be able to:
1. Understand the quality aspects of design for manufacture and assembly.
2. Apply varioustechniques of DFM for product design and assembly.
3. Apply the concept of designs for casting, welding, forming and assembly.
4. Identify the design factors and processes along customer desires for manufacturing.

List of Experiments:

Following is the list of representative exercises. More exercises should exercises should be developed.

1. For a given products/component, identify differences and dissimilarities between Design for
Manufacturing and Design for Assembly.
2. Perform an exercise to identify features (self-locating, self-fastening, minimize orientation during
assembly, retrieval, handling and insertion, symmetry) for assembly of a component.
3. Redesign: Perform exercise for a product to minimize number of parts without compromising its
function.
4. Tolerance stack up analysis: Worst Case tolerance analysis, Statistical tolerance analysis
5. Geometric Dimensioning and Tolerancing inTolerance Analysis.
6. Design evaluation of the components on the basis of casting, welding and machining requirements.
7. Design and manufacture of a plug gauge.