sample presentation without dfm sample 1-1
TRANSCRIPT
Emmanuel K le inJonathan Howarth
Isaac Misr iNathan Schoenknin
Zev scharmm
TEAM 1: Team Hor izonENME 371 - SECTION 0101
November, 11 2010
DFX for the DEWALT DC330B Shoe
Outline
Introduction/ObjectivesDesign for Manufacturing
Functional Requirements
Introduction/Objectives
“DFX is the process in which a product is designed to meet desired design attributes” Manufacturability Assembly …
DFX is necessary in order to create a cheap effective and competitive product
Objectives DFM will be address the shoe die casting process DFA will be looked at the shoe assembly process
DESIGN FOR MANUFACTURING
DFM Shoe: Functional Requirements ffffffff
Dimensional stability Rigid Hard Durable
Easy to assembly Screws?? Attachment to main body??
Flat base To run evenly along surfaces
???
DFM Component: Features
Pivot Indicate pivot angle
Threaded hole for attachment?
Combine with the last slide?
DFM Component: Aluminum Alloy x Die-Cast
Economical Complex shapes
http://www.efunda.com/processes/metal_processing/die_casting.cfm
High degree of accuracy and repeatability
Few secondary processes required Good finish
High Strength to weighthttp://www.aludiecast.com/
Aluminum 380 (UNS A03800) j
Aluminum Association 380 alloy (UNS A03800)
Cast at a temperature of 650 ºCAlloyed with Silicon 8.5%
Increases the melt fluidity Reduces machinability
Copper about 3.5% increases hardness reduces the ductility
http://www.efunda.com/processes/metal_processing/die_casting.cfm
Common Aluminum Alloys for Die Casting *
Material Silicon CopperTensile Strength
Properties
MPa (ksi)AA 380
8.50% 3.50%324
Fair easy to fill(UNS A03800) (47)
AA 38411% 4%
331Easy to fill
(UNS A03840) (48)
AA 3869.50% 0.60%
317 Good corrosion resistance(UNS A03860) (46)
AA 39017% 4.50%
283Good wear resistance(UNS A03900) (41)
http://www.efunda.com/processes/metal_processing/die_casting.cfm
Manufacturing Process
1
2Lubricant is applied to die
Molten aluminum alloy is shot into the casting cavity formed between the two halves of the die (20~120MPa)
http://www.webcitation.org/5tbnPal1W
Aluminum hardens Cooling occurs through
Waterline (water flowing through the die)
Die separates and component is ejected via ejection pins
http://openlearn.open.ac.uk/mod/resource/view.php?id=198352
DIE CAVITYEJECTOR
PINS
MOVINGHALF FIXED
HALF
PLUNGER
LADLECOLDCHAMBER
Manufacturing Process
Someone appreciate this!!!
DIE CAVITYEJECTOR
PINS
MOVINGHALF FIXED
HALF
PLUNGER
LADLECOLDCHAMBER
Die Steels alloy
Ejector pins/platePlunger/Piston
Machinery & Tooling
Cold Chamber Die Cast
Cold chamber Die Casting
Porosity Can’t be heat treated Can’t be welded Reduced ductility
Non of these are functional requirements for the shoe and therefore are not a problem for our DFM
http://www.webcitation.org/5tbnPal1W
Process Parameters:Draw
www.dynacast.com/casting/design/fillet-radii
Because the cast needs to be removed from the die all elements need to be oriented in the direction of the draw die without overhango Expensive inserts or draws can
create overhang but at a high cost
Smart design of the element can usuallymake the use of suchdraws unnecessary.
1
For easy removal of the element a draft is included in the design
Minimum draft angle is about 0.5◦ (30’) DEWALT specifies a
maximum draft of 0.75◦ (45’) for unspecified values on the shoe
Process Parameters:Draft
http://www.efunda.com/processes/metal_processing/die_casting.cfm
Process Parameters:Fillet
• Avoid high stress concentrations– Component and Die-cast
• Internal and External component edges– Every edge except the parting line
• Assist in Filling the Part• DeWALT uses a radius of >>>>
www.dynacast.com/casting/design/fillet-radii
Process Parameters:Fillet 2
www.dynacast.com/casting/design/fillet-radii
Process Parameters:Ribs
Increase the stiffness Add strength Assist in the productionMinimum thickness of walls for aluminum
casts is .9mm
http://www.efunda.com/processes/metal_processing/die_casting.cfm
Materials Applicable for the Process NN
Must have similar physical properties Aluminum Alloys (aluminum/silicon/copper)
ZincCopper Alloys (brass)
MaterialMin. Thickness Min. Draft
Angle (º)mm (in)
Aluminum alloys
0.9 mm0.5
(0.035 in)
Zinc alloys0.9 mm
0.25(0.035 in)
Copper alloys (Brass)
1.25 mm0.7
(.050 in)
http://www.efunda.com/processes/metal_processing/die_casting.cfm
Material Process Selection
Schmidt page 578
Costs
Add image on page 428 of Ashby, 431
Cost of Mass
Cost of Set Tooling
Capital Cost of Equipment
Overhead Cost
Source :Ashby, Michael
Shoe Costs
Advantages and Disadvantages of the Process
Cheap Low cost per unit
High Capital Cost Ineffective for small
production volume
Alternative Processes: Pros and Cons
Ashby 414, 415, 416(422,)Schmidt 574, 575
DFM Guidelines Specific to the Process
DFM Guidelines Specific to the Process
DFM Guidelines Specific to the Process
DFM Guidelines (General)
Evaluation of the Design Against the DFM Guidelines
• Selection of Die Casting Compared to Alternative• Suitability of Aluminum Alloy • Production size?
Evaluation of the Design Against the DFM Guidelines
Evaluation of the Design Against the DFM Guidelines
Evaluation of the Design Against .
the DFM Guidelines
Justification for the Process and Material Used
DFM Conclusions
DESIGN FOR ASSEMBLY
Design for Assembly
What is DFA? Information about the DFA Component/
Subassembly
Assembly Process Used
Design Guidelines for DFA
Evaluation of the Design Against the DFA Guidelines
Evaluation of the Design Against the DFA Guidelines
DFA Conclusions
Summary and Recommendations
References
Additional Information