Chapter 7 Manufacturing Process D id L Design and Layout

Chapter 7 Manufacturing ProcessDesign and Layout• Process Flow Structures• Process Design Tools• Layout Design (chapter 7A)1Manufacturing Process Selection and DesignProcess Flow Structures How to organize material flow basedon product design and competitive dimension?• Continuous process• Flow line, Assembly line• Batch shop: roller coaster ride, sightseeing tour, red wine• Manufacturing Cells (Group Technology)• Job shop (work centers): department store• Project (one-of-a-kind): movies21

Continuous ProcessHighly automated, integratedproduction line. Shutdowns and start-ups are expensivepetroleum, chemicals, beverages3Flow LineDiscrete parts moving at a controlled rate,following the same sequence to build the product.Honda assembly line 3300 ft, 20 off-line branches42

Batch shopProduction with large batchesProduction with small batchesCycleInventoryCycleInventoryProduce SedanProduce Station wagonBeginning ofMonthEnd ofMonthBeginning ofMonthEnd ofMonthBatch sizeCapacity given batch size Setup time Batch size Time per unit5Batch Process andFlow Interruption63

Job ShopSmall batches of many different products, with different processing sequencesDrillingwork center2Assembly2 3323Paintingwork center1441 1MillingLathework centerwork centerA B C D Raw materialsDifficult to estimate the process capacity.7Product-Process Matrix Ex 7.184

Select the Right Process for Your Business• Job/Product Variety• Production Volume• Process/Equipment Flexibility• Quality• Unit Cost 自 動 洗 車 vs. 專 業 汽 車 美 容迴 轉 壽 司 vs. 料 理 壽 司IKEA vs. HOLA快 餐 便 當 店 池 上 vs. 正 忠9Assembly ChartDefines the order of the assemblyand the overall flow patternEx 7.3operationinspectionEx 7.4105

Operation and Route Sheet Ex 7.5Specify process routing, the type of equipment, tooling, andthe content of operations11Design Principle: Equipment SelectionInitial Investment 價 格 、 輔 助 設 備 、 二 手 機 型Output Rate 實 際 產 能Output Quality 精 密 度 、 良 率Operating Requirement 空 間 需 求 , 溫 溼 度 條 件Labor Requirement 人 力 需 求 、 技 術 需 求Flexibility 可 否 生 產 多 種 規 格Setup Requirement 暖 機 或 調 整 生 產 規 格 所 需 時 間Maintenance 維 修 時 間 與 成 本Obsolescence 產 品 是 否 過 時 、 設 備 的 後 續 用 途Systemwide Impact 與 系 統 或 其 他 設 備 的 配 合 、 符 合 作 業 策 略126

Cost Performance• Operations Cost = Fixed Cost + Variable Cost= Administrative Costs + Depreciation and Interest +Production Cost + Inventory and Transportation Cost + …• Operations Cost = Direct Cost + Indirect Cost= Direct Materials Cost + Direct Labor Cost +Overhead and Utilities Cost + …• Net Profit = Revenue– Operations Cost – Taxes• Profit Margin = Net Profit / Revenue• Return on Assets = Net Profit / Total Assets13Example 7.2 Manufacturing Process Analysis6 machines, 25 × 6 parts/hr15 workers,150 components/hrWeekly production = 150 × 8 × 6 = 6000147

Cost Analysis15Design Principle: Break-Even AnalysisOutsourcing cost=$200demandLathe cost=$80,000+$75 demandMachine Center Cost= $200,000+$15 demandEx 7.2168

7A Facility LayoutDetermine the placement of departments, workgroups withindepartments, workstations, machines, and stock-holding pointswithin a facility to ensure a smooth job (customer)flow.• Process Layout (job-shop or functional layout) hospitals, department store• Product Layout (flow-shop layout)• Group Technology Layout mall• Fixed-Position Layout construction, art sculpture17Process Structure are not the same as Layouts• A process describes the set of operations requiredfor a product and the sequence of the operations. Itdoes not specify the actual size and location of eachoperation.• A layout specifies the size and location of eachdepartment and thus determine the space requiredand the material or customer movement. It does notspecify what operations are required for each product.189

Process Layout for Job ShopAdjust the relative placement to minimize the trafficActivity Relationship ChartFromTo2 3 4 5I U E U1. Credit department6 -- 4 --U I A2. Toy department-- 1 1,6U X3. Wine department-- 1X4. Camera department15. Candy departmentArea(sq. ft.)100400300100100Exhibit 7A.8LetterCloseness ratingNumberReason forrating19Systematic Layout Planning for Process LayoutJob shop1 E3I4XX2A552 4 3120 ft25 1 4350 ft2010

Product Layout for Flow Linetask1task….task task2 n-1 n• 須 按 照 既 定 順 序 逐 步 完 成 所 有 作 業 步 驟• 將 作 業 步 驟 分 配 至 各 工 作 站 , 由 各 站 人 員 負 責 執 行Key: 在 不 違 反 作 業 順 序 的 前 提 下 , 平 均 分 配 工 作 量Lucy and Ethel21Line Balancing for Product LayoutAllocate work elements to be done among stations so that the number ofstations is minimized while meeting the production goal.Example 7A.1420 minutes per day, 500 products per dayefficiency=195/(550.4)=0.772211

ScooterAssembly161 scooters/week231 302 253 1004 665 1146 497 668 1009 3010 4311 5112 11813 11014 5915 3316 9617 13518 8419 5620 7521 9522 2023 4324 11425 9426 847926484501 302 253 1004 665 1146 497 668 1009 3010 4311 5112 11813 11014 5915 3316 9617 13518 8419 5620 7521 9522 2023 4324 11425 9426 846747664501 302 253 1004 665 1146 497 668 1009 3010 4311 5112 11813 11014 5915 3316 9617 13518 8419 5620 7521 9522 2023 4324 11425 9426 846746355811 302 253 1004 665 1146 497 668 1009 3010 4311 5112 11813 11014 5915 3316 9617 13518 8419 5620 7521 9522 2023 4324 11425 9426 84161 scooters/week 164 186 1896236026652412

3. Grouping machinesinto cellsBenefits for GT Layoutbenefits of product layout in job-shop environmentBetter human relationsImproved operator expertiseFaster production setupLess WIP and material handling27Dell’s Server Plant Uses Manufacturing CellsStrategy: build to order (flexibility)Dell uses cells toachieve both velocityand flexibilityp.2342814

Conclusion• World class enterprises excel at the speedy andflexible integration of the manufacturing processes.• Design process flow before you build the actualsystem.• What is the difference between process structureand facility layout?• Use a combination of process structures tomaintain flexibility.2915