PEMILIHAN PROSES MANUFAKTUR (From Design to Manufacture)

Transkripsi

1 PEMILIHAN PROSES MANUFAKTUR (From Design to Manufacture) Dr. M.K. Herliansyah, ST. MT. Program Studi Teknik Industri Jurusan Teknik Mesin dan Industri Fakultas Teknik Universitas Gadjah Mada 2010

2 Alasan Pemilihan Proses Manufaktur: Hasil sesuai Yang Diinginkan Efisien Murah Cepat Kualitas Baik

3 Permasalahan : Kompetisi / persaingan ketat Harapan konsumen yang semakin tinggi Bisnis Manufaktur Memperbaiki kualitas Harga jual murah Penyediaan yang cepat Menaikkan efisiensi Perbaikan kualitas Investasi/otomatisasi Penurunan cost Mesin-mesin yang advance Pemilihan proses yang tepat (efisien + ekonomis) Teknologi dan biaya perancangan

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5 MANUFACTURING INFORMATION FOR DESIGN Produk mengalami perubahan sebelum sampai ke konsumen

6 Faktor-faktor Pertimbangan Dalam Pemilihan Proses Manufaktur : a. Jumlah produk b. Biaya peralatan (equipment) c. Biaya tooling d. Waktu proses e. Intensitas pekerja f. Supervisi proses g. Perawatan h. Konsumsi energy + overhead cost

7 Cont i. Biaya material + ketersediaannya j. Bentuk dan dimensi komponen k. Toleransi yang diperlukan l. Surface finish m. Bulk treatment n. Keragaman komponen o. Limbah/sisa p. Daur ulang komponen/recycling

8 Agar produk yang dihasilkan kompetitif, identifikasi fisibilitas teknologi dan ekonomi dari kombinasi proses manufaktur dan bahan, E X A M P L E

9 A PROCESS SELECTION STRATEGY diperlukan suatu metode atau alat untuk memilih proses yang sesuai dan mengestimasi biaya se-awal mungkin. PRIMA (Process Information Maps) bertujuan : memberikan informasi mengenai proses yang tepat untuk pembuatan suatu komponen

10 Strategi!!! a. Tentukan atau perkirakan kuantitas produk dalam setahun b. Pilihlah bahan yang sesuai dengan spesifikasi desain c. Pilihlah alternative proses yang sesuai menurut PRIMAs d. Pertimbangkan setiap alternative tersebut berdasarkan persyaratan engineering dan ekonomi: i. Mengerti proses dan variasinya ii. iii. iv. Mempertimbangkan kesesuaian bahan dan proses Assess conformance of component concept with design rules Compare tolerance and surface finish requirements with process capability data

11 Cont e. Mempertimbangkan posisi ekonomi dari proses dan dapatkan estimasi biaya komponen dari setiap alternative f. Sesuaikan proses manufaktur yang telah dipilih dengan persyaratan bisnis.

12 Design for X Topics Design for Manufacturing Design for Assembly Design for Production Design for Recycling/Disposal Design for Life Cycle Prototyping Design for Automation

13 Gathering DFM Information Design documents: Sketches, Drawings, Spesifikasi produk, dan Alternatif-alternatif desain. Pemahaman dan informasi detil mengenai proses produksi dan perakitan/assembly Perkiraan: manufacturing costs, production volumes, dan ramp-up timing.

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15 DFM Method Memperkirakan manufacturing costs. Mengurangi biaya-biaya untuk mempersiapkan/pembuatan components. Mengurangi biaya-biaya untuk proses perakitan/assembly. Mengurangi biaya-biaya pendukung proses production. Mempertimbangkan dampak/pengaruh DFM decisions pada faktor-faktor yang lain.

16 Proposed Design DFM Method Estimate The Manufacturing Cost Reduce the Cost of Components Reduce the Cost of Assembly Reduce the Cost of Supporting Production Consider the Impact of DFM Decisions on Other Factors Recompute the Manufacturing Costs N Y Good Enough? Acceptable Design

17 Estimate the Manufacturing Costs Equipment Information Tooling Raw Materials Labor Purchased Components Manufacturing System Finished Goods Energy Supplies Services Waste

18 Manufacturing Costs Defined Menghitung seluruh pengeluaran untuk input system (sebagai contoh: pembelian komponen-komponen, energi, raw materials, dan lain-lain) dan pengeluaran untuk penanganan limbah yang dihasilkan oleh sistem.

19 Elements of the Manufacturing Cost of a Product Manufacturing Cost Components Assembly Overhead Standard Custom Labor Equipment and Tooling Support Indirect Allocation Raw Material Processing Tooling

20 Manufacturing Cost of a Product Component Costs (komponen-komponen dari produk yang dibuat) Komponen-komponen yang dibeli dari supplier Custom parts yang dibuat didalam shop floor-nya sendiri atau shop floor para supplier sesuai dengan spesifikasi desain dari manufacturer s Assembly Costs (labor, equipment, & tooling) Overhead Costs (all other costs) Support Costs (material handling, quality assurance, purchasing, shipping, receiving, facilities, etc.) Indirect Allocations (tidak berhubungan secara langsung dengan suatu particular product tetapi harus dibayar dalam proses bisnis)

21 Fixed Costs vs. Variable Costs Fixed Costs ditentukan terlebih dahulu dalam suatu jumlah tertentu tanpa memperhatikan jumlah unit yang diproduksi (i.e. setting up the factory work area or cost of an injection mold) Variable Costs ditentukan secara langsung dalam jumlah yang proporsional dengan jumlah unit yang diproduksi (i.e. cost of raw materials)

22 Reduce the Cost of Components 1. Understand the Process Constraints and Cost Drivers 2. Redesign Components to Eliminate Processing Steps 3. Choose the Appropriate Economic Scale for the Part Process 4. Standardize Components and Processes 5. Adhere to Black Box Component Procurement

23 1. Understand the Process Constraints and Cost Drivers Redesign costly parts with the same performance while avoiding high manufacturing costs. Work closely with design engineers raise awareness of difficult operations and high costs.

24 2. Redesign Components to Eliminate Processing Steps Reduce the number of steps of the production process Will usually result in reduce costs Eliminate unnecessary steps. Use substitution steps, where applicable. Analysis Tool Process Flow Chart and Value Stream Mapping

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27 3. Choose the Appropriate Economic Scale for the Part Process Economies of Scale As production volume increases, manufacturing costs usually decrease. Fixed costs divided among more units. Variable costs are lower since the firm can use more efficient processes and equipment.

28 4. Standardize Components and Processes Economies of Scale The unit cost of a component decreases as the production volume increases. Standard Components common to more than one product Analysis tools group technology and mass customization

29 5. Adhere to Black Box Component Procurement Black box only give a description of what the component has to do, not how to achieve it Successful black box design requires clear definitions of the functions, interfaces, and interactions of each component.

30 DFM Tools and Methodology Tools and Methodologies Design For Assembly (DFA), (IBM experience) Failure Mode and Effect Analysis (FMEA), (Sun example) Taguchi Method, (Hitachi experience) Value Analysis-- Value Engineering (HP example) Quality Function Deployment (QFD), Going to the Gemba (Hitachi) Group Technology, (IBM example) Cost management and optimization, SPC, Six-Sigma (Motorola), TQC, etc

31 DFA Systems Boothroyd Dewhurst DFM & A Munro & Assoc. (Design Prophet/Profit) Others

32 DFM/A System In Global Manufacturing

33 Commercial Airplanes - Military Aircraft & Missiles - Space & Communications - Air Traffic Management - Boeing Capital Corporation - Shared Services Group - Phantom Works

34 747 Final Assembly at Everett, Washington

35 747 Freighter

36 747 Freighter

37 DFM Tools: DFA Guidelines - One assembly direction tops down -No adjustments required -No hidden features - Easy to fabricate parts - Standard parts (one screw type) - Test direction access from top - Parts are self-guiding - Sub-assemblies reduce handling of small hard to grip parts - Avoid tangle with use of fixtures - Symmetry in two axis - Holes large enough (straightness issues if too deep) - Common datum s for all fixtures -One common plane for assembly - Tabs for robotic lift -Die cast with minimal amount of holes (debris chip) -Standard cutters -Guide features - bottom rails for conveyor

38 DFM Tools: DFA Guidelines Summary of DFA Guidelines 1. Minimize the number of parts 2. Standardize and use as many common parts as possible 3. Design parts for ease of fabrication (use castings without machining and stampings without bend) 4. Minimize the number of assembly planes (Z-axis) 5. Use standard cutters, drills, tools 6. Avoid small holes (chips, straightness, debris) 7. Use common datum s for tooling fixtures 8. Minimize assembly directions 9. Maximize compliance; design for assembly

39 DFM Tools: DFA Guidelines Summary of DFA Guidelines 10. Minimize handling 11. Eliminate adjustments 12. Use repeatable, well understood processes 13. Design parts for efficient testing 14. Avoid hidden features 15. Use Guide features 16. Incorporate symmetry in both axis 17. Avoid designs that will tangle. 18. Design parts that orient themselves

40 DFM Tools and Methodology FMEA (Failure Mode and Effects Analysis) Method for analyzing the causes and effects of failures. Highlights designs and assemblies most likely to cause failures. Helps identify and prioritize corrective action Indicates where the most improvement in terms of severity, frequency, and detectability can be made. Widely used manufacturing technique (Mil standards, SAE, ANSI Specs)

41 Reduce the Costs of Assembly 1. Design for Assembly (DFA) index 2. Integrated Parts (Advantages and Disadvantages) 3. Maximize Ease of Assembly 4. Consider Customer Assembly

42 1. Design for Assembly Index DFA index = (Theoretical minimum number of parts) x (3 seconds) Estimated total assembly time

43 Determining the Theoretical Minimum Number of Parts Does the part need to move relative to the rest of the assembly? Must the part be made of a different material from the rest of the assembly for fundamental physical reasons? Does the part have to be separated from the assembly for assembly access, replacement, or repair?

44 2. Advantages of Integrated Parts Do not have to be assembled Often less expensive to fabricate rather than the sum of each individual part Allows critical geometric features to be controlled by the part fabrication process versus a similar assembly process

45 2. Disadvantages of Integrated Parts Conflict with other sound approaches to minimize costs Not always a wise strategy

46 3. Maximize Ease of Assembly Part is inserted from the top of the assembly Part is self-aligning Part does not need to be oriented Part requires only one hand for assembly Part requires no tools Part is assembled in a single, linear motion Part is secured immediately upon insertion

47 4. Consider Customer Assembly Customers will tolerate some assembly Design product so that customers can easily and assemble correctly Customers will likely ignore directions

48 Reduce the Costs of Supporting Production Minimize Systemic Complexity (inputs, outputs, and transforming processes) Use smart design decisions Error Proofing (Poka Yoke) Anticipate possible failure modes Take appropriate corrective actions in the early stages Use color coding to easily identify similar looking, but different parts

49 Consider the Impact of DFM Decisions on Other Factors Development Time Development Cost Product Quality External Factors Component reuse Life cycle costs

50 DFM&A Road Map Membentuk sebuah multifunctional team Menetapkan sasaran produk melalui competitive benchmarking Melakukan DFA analysis Melakukan segmentasi produk hingga mencapai manageable subassemblies atau levels of assembly Sebagai sebuah team, menggunakan prinsip-prinsip DFA Menggunakan teknik-teknik kreatif untuk meningkatkan desain yang dihasilkan Sebagai sebuah team, melakukan evaluasi dan memilih ide rancangan yang terbaik Memastikan bahwa setiap bagian komponen diproduksi pada level yang ekonomis Menentukan target cost untuk setiap komponen dalam desain produk yang baru

51 TERIMA KASIH ATAS PERHATIAN DAN KERJASAMANYA Dr. Muhammad K. Herliansyah, ST. MT.