Sample Presentation Without DFM Sample 1-1

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