Design for Manufacture &Design for Manufacture &DFXDFX

Park, Mok-Min

2004, 05, 10MAI Lab. Seminar

Design for manufacture and design for ‘X’: Design for manufacture and design for ‘X’: concepts, applications, and perspectivesconcepts, applications, and perspectives

Computers & Industrial Engineering 41 (2001) 241-260

Tsai-C. Kuo, Samuel H. Huang, Hong-C. Zhang

Dept. of IE and Mgt, Minghsin Institute of Technology, Hsinchu, Taiwan, ROC Dept. of ME, IE, and NE, Univ. of Cincinnati, USA Dept. of IE, Texas Tech Univ., USA

Historical backgroundHistorical background

Engineering design 원하는 요구를 만족시키기 위하여 시스템 , 컴포넌트나

프로세스를 개발하는 일련의 과정 Two approaches: after a design is completed

Value Engineering (VE): 제품의 기능과 가격을 고려 Producibility Engineering (PE): 가용한 기술과 툴을 이용하여

적절한 비용으로 생산 Limits of VE & PE

제품의 제조 가능성을 초과하는 최적해 VE 는 과학적인 접근보다는 회사의 정책에 연관 디자인이 결정되면 대부분의 비용이 이미 결정

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Design for Assembly (DFA)Design for Assembly (DFA)

Boothroyd & Dewhurst(1987)’s DFA method 기본적인 기준을 이용하여 각 부품이 왜 필요하고 다른 부품과

합쳐져야 하는지에 대해서 자문 특별히 구축한 DB 의 실시간 표준을 이용하여 조립 시간을 개산 Design efficiency 는 실제 조립 시간과의 비교를 통하여 구함 제조나 품질에서 문제를 일으킬 수 있는 assembly difficulty 를 파악

Two factors The total number of parts The ease of handling, insertion, and fastening of the part

Applications Hitachi: Assembly Evaluation Method (AEM) Sony: Design for Assembly Cost effectiveness (DAC) GE: manufacturing producibility handbook, workshops

DFEDFA DFM DFD DFR DFLC DFQ DFMt 2/20

Design for Manufacture (DFM)Design for Manufacture (DFM)

Processes for the manufacture of a particular part 원자재 선택 표준 컴포넌트 사용 프로세스 선택 범용 부품 설계 모듈 디자인 개발 조립 방위 최소화

Stoll(1988) cited a checklists of DFM guidelines Many DFM studies have been completed

Machining parts (Booth & Radovanovic, 1989) injection molding (Dewhurst, 1987) sheet metal stamping (Zenger & Dewhurst, 1988) die cast parts (Dewhurst & Blum, 1989)

DFM applications can be carried out with great efficiency via a CAD/CAM system

DFEDFA DFM DFD DFR DFLC DFQ DFMt 3/20

Design for disassembly (DFD)Design for disassembly (DFD)

Two basic methods of disassembly (Leonard, 1991) reverse assembly, brute force

Some obstacles (Seliger, Zussman & Kriwet, 1993) Difficult to gain all the information Parts might have been modified during repair Wear can make joined elements

Determination of disassembly sequence Dewhurst(1991) Gu and Yan(1995): a graph-based heuristic approach Etc.

DFEDFA DFM DFD DFR DFLC DFQ DFMt 4/20

Design for recyclability (DFR)Design for recyclability (DFR)

Environmental conscious increases The aim of recycling

Maximize the recycling resources Minimize the mass and pollution potential of

remaining products DFM of plastics that can be easily recycled Dismantling techniques and recycling costs

DFEDFA DFM DFD DFR DFLC DFQ DFMt 5/20

Design for environment (DFE)Design for environment (DFE)

Three main goals of DFE (Hovath, et al. , 1995) Minimize the use of non-renewable resources Effectively manage renewable resources Minimize toxic release to the environment

HP provides DFE tools (Korpalski, 1996) DFE guidelines Product assessments Product stewardship metrics

DFEDFA DFM DFD DFR DFLC DFQ DFMt 6/20

Design for life-cycle (DELC)Design for life-cycle (DELC)

Product life-cycle cost (Jovane, 1993)

DFEDFA DFM DFD DFR DFLC DFQ DFMt

Life-cyclephase

Company costs User costs Society cost

Need market recognition

Design development

Productionmaterials, energy, facilities,wages, and salaries

Waste, pollution, health damages

Distribution transportation, storage, wastetransportation, storage

Waste, pollution, packing, health damages

Use warranty serviceenergy, materials, maintenance

Waste, pollution, health damages

Disposal disposal duesWaste, pollution, disposal, health damages

Recycling recycling dues Waste, pollution, health damages

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Design for quality (DFQ)Design for quality (DFQ)

The objectives of DFQ (Crow, 1983) Meet customer requirements Robust product Continuously improve product reliability,

performance, and technology Methods of DFQ

Taguchi method(1986) Quality Function Deployment (QFD) Benchmarking

DFEDFA DFM DFD DFR DFLC DFQ DFMt 8/20

Design for maintainability (DFMt)Design for maintainability (DFMt)

Maintainability is (Kapur & Lamberson, 1977) The probability that a failed system can be repaired in a specific int

erval of downtime Objective of DFMt

The product can maintained throughout its useful life-cycle at reasonable expense without any difficulty

Maintainability design guidelines 접근성 고장의 확인 및 격리 능력 교체 부품의 비중 한계 교체 부품의 운반 가능성을 고려한 크기 한계 교체 부품의 자동 ( 원격 ) 교체 가능성

DFEDFA DFM DFD DFR DFLC DFQ DFMt 9/20

SummarySummary

여러 측면에서의 설계 목적과 제약 사항들을 사전에 고려하여 더 나은 제품을 설계

DFMA 를 통해서 낮은 비용으로 용이한 제품 생산 DFD, DFR, DFLC 를 통해서 제품의 수명 주기 후에

처리를 용이 DFE 를 통해서 환경적인 안전과 건강과 관련된

문제들을 해결하고 간접적인 비용을 절감 DFQ, DFMt 를 통해서 검사 , 재작업 , 진단에

소요되는 비용을 절감

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Future trendsFuture trends

Integration issues in DFX Systematic identification of user’s life-cycle requirements Methods to represent, store, and retrieve design

alternatives Comprehensive measure of goodness of a design

Human factors engineering in DFX Workplace design, human-equipment interface, training

program Intelligent DFX systems

필요한 경험을 쌓는 데 많은 시간이 소요 Knowledge-based system 을 이용하여 design feature 간의

관계를 이해하는 데 도움을 줄 수 있다 .

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Productivity evaluation method andProductivity evaluation method anddesign for manufacturabilitydesign for manufacturability

JSAE Review 16 (1995) 375-381

Hiroshi Onitsuka, Kaoru Eguchi, Naoaki Miura, Hiroatsu Matsumura

Powertrain Prototype Engineering Department, Nissan Motor Co., Ltd., Kanagawa, Japan

IntroductionIntroduction

Nissan 에서 미국 시장을 겨냥하여 개발한 VQ engine에 적용된 방법론

높은 품질과 낮은 비용이 목적 엔진 조립 공정의 70% 가 자동화

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Productivity evaluation methodProductivity evaluation method

The degree of progress achieved in design for manufacturability

The evaluation method provides an index of how difficult a part would be to build, or the poorness of its workability

Stabilize production quality and achieve low cost level

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Assembly productivity evaluation methodAssembly productivity evaluation method

Standard time Most fundamental work aspects of an element 부품을 줄이는 것으로 향상 가능

Difficult operation time Additional time spent when the construction of a part requires extra

work 제거 가능한 다양한 방식의 작업이 존재

어떤 부품이 생산성 증가를 위하여 개선 가능한 지를 알려줌 Std time/dif oper time 중 어느 것이 효과적인 지 알려줌 제품 개발 초기 단계에 전체 line cycle time 에 대한 추정

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Maching productivity evaluation methodMaching productivity evaluation method

Cost of facilities 와 cost of the tools 로 평가 예를 들어 , 가공해야 할 hole 의 수가 많으면 ,

standard operation score 가 높다 . Hole 들이 가까이 있는 경우에는 multi-axis head 를

사용할 수 없기 때문에 difficult operation score 가 높다 .

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Design for global manufacturing and assemblyDesign for global manufacturing and assembly(DFGMA)(DFGMA)

IIE Transactions 29 (1997) 585-597

G. Don TaylorDept. of IE, Bell Engineering Center, Univ. of Arkansas, USA

IntroductionIntroduction

Dowlatshahi(1992) reports The design phase is responsible for only 5% of product

cost But, it can determined 75% of the manufacturing cost and

80% of product quality performance

General DFX strategies are difficult to manage in multi-facility, global settings

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Mathematical formulationMathematical formulation

Manufacturing cost

manufacturing= process + design + logistics + inventory

ijklmijklmijklmijklmijklm CICLCDCPCM

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General DFGMA modelGeneral DFGMA model

Objective function:

m

IjklmIjklmlkj

XCM:min

l

IjklIjklkj

YCS

k

IjkIjkj

YCT '

l

jkljklkj

ZCC

manufacturing cost

set-up cost

tooling cost

capital procurement cost

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i : product Ij : process j (1:automated, little flexible, 2: flexible)k : site k (Europe, Asia, North America)l : period l(3 quarter period)m : demand location

General DFGMA modelGeneral DFGMA model

constraints

l

lml

Ijklmkj

DX

jklm

ijklmIjklm

ijklm

I

iijkl AXCXC

)()(1

1

)]([ Ijklm

Ijklm YMX

10 jkA

)('1, jkljklljkjkl ZAAA

0jklA

int,0IjklmX

int,1,0' IjkY

int,1,0IjklY

int,1,0jklZ

)']([ Ijkl

Ijkl YMX

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i : product Ij : process j (1:automated, little flexible, 2: flexible)k : site k (Europe, Asia, North America)l : period l(3 quarter period)m : demand location

simulationsimulation

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