A SEMINAR ONDESIGN FOR MANUFACTURING

ASSEMBLY PROCESS

SUBMITTED BYD.SANTOSH KUMAR14481D1506

• 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

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

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

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

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

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

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

Proposed design of a motor drive assembly

REDUCE PARTS:

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.

At the end of the changes due to DFMA are:

STANDARDIZED PARTS:

Easier = faster

Less opportunity for mistakes

Easier to automate

Simplification of assembly:

• Less steps = faster

• Less material handling = less damage

• Less operations = less opportunity for defects

Reducing Number of Processes

Less Fasteners especially screws & bolts

Left to right: simplest, low cost to most parts hardest to assembly

SELF LOCKING AND SELF-FASTENING

SELF LOCATING PARTS

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

Rivet

Eliminate Secondary Operations

Screwing, drilling, twisting, riveting, bending Welding, soldering, gluing, Painting, lubricating

ENSURE ACCESS & VISIBILITY

Easy part handling

size slipperiness

sharpness flexibility

Size WeightShapeSharp edgesStickyTangled & Nested

Eliminate Tangling/Nesting

Assemble from Top

Insertion from the top is preferred.

Reduce locating/alignment operations –manual/time consuming

Any Queries