ASSEMBLY

1. A SEMINAR ON
DESIGN FOR MANUFACTURING
ASSEMBLY PROCESS
SUBMITTED BY
D.SANTOSH KUMAR
14481D1506

2. • Design for manufacturing (DFM) is design
based on minimizing the cost of
production and/or time to market for a
product, while maintaining an
appropriate level of quality. The strategy
in DFM involves minimizing the number
of parts in a product and selecting the
appropriate manufacturing process.
Design for Manufacturing

3. DIFFERENCES:
Design for Assembly (DFA)
• concerned only with reducing product assembly cost
– minimizes number of assembly operations
– individual parts tend to be more complex in design
Design for Manufacturing (DFM)
• concerned with reducing overall part production cost
– minimizes complexity of manufacturing operations
– uses common datum features and primary axes

4. DESIGN FOR ASSEMBLY
“A PROCESS FOR IMPROVING PRODUCT
DESIGN FOR EASY LOW-COST ASSEMBLY,
FOCUSING ON FUNCTIONALITY AND ON
ASSEMBLABLITY CONCURRENTLY.”
-VINCENT CHAN &FILIPPO.
Design of components taking into account how they will
be assembled together to ensure that assembly costs are
minimized.
DFA is the method of design of the product for ease of
assembly

5. Manual
Most flexible & Most expensive
Skill of workers effects assembly times
Hard Automation
Custom tooling – only make one product
Soft Automation
Robots
Types of Assembly

6. Concept Design
Design for
Assembly
Design for
Manufacturing
Detailed Design
Optimize Design for
Part Count and
Assembly
Optimize Design for
Production Readiness
Sequence of Analysis

7.  Product Information: functional requirements
 Functional analysis
 Identify parts that can be standardized
 Determine part count efficiencies
Step 2
Step 1
 Analyze data for new design
Step 3
 Identify handling (grasp & orientation) opportunitiesStep 4
 Identify insertion (locate & secure) opportunitiesStep 5
Step 6  Identify opportunities to reduce secondary operations
 Identify quality (mistake proofing) opportunities
Benchmark when possible
 Determine your practical part count
Step 7
DFA Process

8. 1. Reduce number of parts
2. Reduce number of different parts - Standardize parts
3. Simplification of assembly
4. Reduction number of processes
5. Less fasteners especially screws & bolts
6. Design parts with self-locating features
7. Design parts with self-fastening features.
8. Minimize reorientation of parts during assembly
9. Ensure access & visibility
10. Easy part handling
11. Assemble from top
12. Reduce locating/alignment operations – manual/time
consuming
DFA Guidelines

9. Proposed design of a motor drive assembly
REDUCE PARTS:

10. The following change could easily be made:
 the powder metal bushings are unnecessary because the part can be
machined from an alternative material with the right frictional characteristics,
such as Nylon
The following are difficult to justify:
 separate stand-offs
 end plate
 cover
 the six screws
We started with this.

11. At the end of the changes due
to DFMA are:

12. STANDARDIZED PARTS:

13. Easier = faster
Less opportunity for mistakes
Easier to automate
Simplification of assembly:

14. • Less steps = faster
• Less material handling = less damage
• Less operations = less opportunity for defects
Reducing Number of Processes

15. Less Fasteners especially screws & bolts
Left to right: simplest, low cost to most parts hardest to assembly

16. SELF LOCKING AND SELF-FASTENING

17. SELF LOCATING PARTS

18. Asymmetric Part Symmetry of a part
makes assembly easier
Symmetry eliminates reorientation
1. Critical orientation – obvious – see & fit
2. Non-critical orientation – fit in any direction

19. Rivet
Eliminate Secondary Operations
Screwing, drilling, twisting, riveting, bending Welding,
soldering, gluing, Painting, lubricating

20. ENSURE ACCESS & VISIBILITY

21. Easy part handling
size slipperiness
sharpness flexibility
Size
Weight
Shape
Sharp edges
Sticky
Tangled & Nested

22. Eliminate Tangling/Nesting

23. Assemble from Top
Insertion from the top is
preferred.

24. Reduce locating/alignment operations –
manual/time consuming

25. Any Queries