Lecture 2 Selecting the manufacturing processeskaizenha.com/cdn/files/Manufacturing 1/Lecture...
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Lecture 2 Selecting the manufacturing processes
Transcript of Lecture 2 Selecting the manufacturing processeskaizenha.com/cdn/files/Manufacturing 1/Lecture...
Lecture 2 Selecting the
manufacturing processes
Final Design
Preliminarydesign
Material selection
ManufacturingProcess
Selection
Ideageneration
FeasabilityStudy
ProductFessible
?
DFA
DFEDFM
Yes
No
Proto type
Design Process
Preliminarydesign
• Function (what does the component do)
• Objective (what is to be maximized or minimized)
• Constraints(what essential conditions to be met)
• Free variables (which design variables are free)
Design Requirements
• Functional drawing, flowcharts, sketches
• Rough component sizing
Design Concept
• Stresses, size, shape, thickness, …etcDesign
Calculations
components function?
Källa: Volvo
Källa: Volvo
Linkarm
Check for DFM and DFA
• DFA
– how easily things can be assembled
– DFA: Design of components taking into account how
they will be assembled together to ensure that assembly
costs are minimized.
• DFM – how easily things can be made
– DFM: Design of components taking into consideration
the processes that will be used to manufacture them to
ensure that manufacturing costs are minimized.
• DFMA – balance between ease of making & assembly
DFA Example:Design Simplification
•Link between function and required properties Define a “performance index” as strength (Ashby Maps)
Performance
ProcessingCharacteristics
•Process costCost
-Weldability
-Machinability
.Material selection
Data organisation
ManufacturingProcess
Selection
Material-Process
compatibility
Size-Process compatibility
Shape-Process compatibility
Cost
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Sand casting
Shapin
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Die casting
Investment casting
Low pressure casting
Forging
Extrusion
Sheet forming
Powder Methods
Electro machining
Conventional
machining
Injection molding
Blow molding
Compression
molding
Rotational molding
Thermo molding
Polymer casting
Resin-Transfer
molding
Filament winding
Lay-up method
Vacuum bag
processes can be split up into:
shaping: e.g. forging, rolling, casting, blow moulding, vacuum forming
Finishing: e.g. grinding, drilling
Joining: e.g. soldering, gluing
Material-Process compatibility
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Therm
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AdhesivesWelding, metalsWelding, polyemrsFaseners
Fin
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Precision machiningGrindingLappingPolishing
Metal
Ceramics
Polymers
Polymer foams
Composites
Size-Process compatibility
Can we make something this size? For instance, you can't die-cast an engine
block - it's too big.
Is the processes suitable for the shape we need? For example: tubes are long and
thin so ideal for extrusion but not casting; and you can't blow-mould a telephone
case because of all the holes in it!
Will we get the finish we want? Both dimensional tolerance (accuracy) and
surface roughness (smoothness) are strongly influenced by which process is used,
for instance sand casting is poor for both whilst die-casting is very good.
How good will the quality be? This is the most difficult problem to address and
usually there is little that can be said without actually trying it! However, we can
sometimes make rough comparisons - for instance sand castings can often be
porous and so might not be very strong.
Sand casting
Die casting
Investment casting
Low pressure casting
Forging
Extrusion
Sheet forming
Powder Methods
Electro machining
Conventional machining
Injection molding
Blow molding
Compression molding
Rotational molding
Thermo Forming
Polymer casting
Resin-Transfer molding
Filament winding
Lay-up method
Vacuum bag
10-3 10-2 0.1 1 10 102 103 104Mass (kg)
Shape-Process compatibility
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3-D
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Sand casting
Die casting
Investment casting
Low pressure casting
Forging
Extrusion
Sheet forming
Powder Methods
Electro machining
Conventional machining
Injection molding
Blow molding
Compression molding
Rotational molding
Thermo Forming
Polymer casting
Resin-Transfer molding
Filament winding
Lay-up method
Vacuum bag
Weight of the disk is 5,0kg.
Ex choose a manufacturing process for the brake disk
