Bab 9-10 Tata Letak Fasilitas

Tahap terakhir dari perencanaan sebelum produksi terjadi Penjadwalan Menentukan kapan tenaga kerja, peralatan, fasilitas yang diperlukan untuk menghasilkan suatu produk atau memberikan layanan Tahap terakhir dari perencanaan sebelum produksi terjadi

Tujuan Fasilitas Tata Letak Meminimalkan biaya penanganan material Memanfaatkan ruang secara efisien Memanfaatkan tenaga kerja secara efisien menghilangkan hambatan Memfasilitasi komunikasi dan interaksi antara pekerja , antara pekerja dan supervisor mereka , atau antara pekerja dan pelanggan Reduce manufacturing cycle time or customer service time

Tujuan Fasilitas Tata Letak Menghilangkan limbah yang berlebihan Memfasilitasi masuk, keluar , dan penempatan material, produk , atau orang- orang menggambungkan ukuran keselamatan dan keamanan Mempromosikan produk dan layanan berkualita Mendorong kegiatan perawatan yang tepat Memberikan kontrol visual operasi atau kegiatan Memberikan fleksibilitas untuk beradaptasi dengan perubahan kondisi Meningkatkan kapasitas

Jenis dasar Layouts Process Layout Mesin dikelompokkan berdasarkan proses yang mereka lakukan Product Layout Susunan linear dari workstation untuk menghasilkan produk tertentu Fixed Position Layout Digunakan dalam proyek di mana produk tersebut tidak dapat dipindahkan

Process Layout pada Jasa Women’s lingerie Women’s dresses Women’s sportswear Shoes Cosmetics and jewelry Entry and display area Housewares Children’s department Men’s department Figure 5.1

Manufacturing Process Layout D G A Receiving and Shipping Assembly Painting Department Lathe Department Milling Department Drilling Department Grinding P Figure 5.2

Manufacturing Process Layout D G A Receiving and Shipping Assembly Painting Department Lathe Department Milling Department Drilling Department Grinding P Figure 5.2

Manufacturing Process Layout D G A Receiving and Shipping Assembly Painting Department Lathe Department Milling Department Drilling Department Grinding P Figure 5.2

A Product Layout In Out Figure 5.3

Comparison Of Product And Process Layouts PRODUCT LAYOUT PROCESS LAYOUT 1. Description Sequential arrangement Functional grouping of machines of machines 2. Type of Process Continuous, mass Intermittent, job shop production, mainly batch production, assembly mainly fabrication 3. Product Standardized Varied, made to stock made to order 4. Demand Stable Fluctuating 5. Volume High Low 6. Equipment Special purpose General purpose 7. Workers Limited skills Varied skills Table 5.1

Comparison Of Product And Process Layouts PRODUCT LAYOUT PROCESS LAYOUT 8. Inventory Low in-process, High in-process, high finished goods low finished goods 9. Storage space Small Large 10. Material Fixed path Variable path handling (conveyor) (forklift) 11. Aisles Narrow Wide 12. Scheduling Part of balancing Dynamic 13. Layout decision Line balancing Machine location 14. Goal Equalize work at Minimize material each station handling cost 15. Advantage Efficiency Flexibility Table 5.1

Fixed-Position Layouts Tipe proyek Peralatan , pekerja , bahan , sumber informasi lainnya dibawa ke situs Tingginya Tenaga kerja terampil Sering rendah tetap Biaya Tipe biaya variabel biasanya tinggi

Designing Process Layouts Meminimalkan biaya material handling Blok Diagram Minimize nonadjacent loads Minimalkan beban nonadjacent Gunakan ketika data kuantitatif yang tersedia avalaibel hubungan Diagram Berdasarkan preferensi lokasi antara area Gunakan ketika data kuantitatif tidak available

Process Layout Load Summary Chart Department 1 2 3 4 5 1 — 100 50 Example 5.1 Department 1 2 3 4 5 Load Summary Chart FROM/TO DEPARTMENT 1 — 100 50 2 — 200 50 3 60 — 40 50 4 100 — 60 5 50 — Composite Movements Composite Movements 2  3 200 loads 3  5 50 loads 2  4 150 loads 2  5 50 loads 1  3 110 loads 3  4 40 loads 1  2 100 loads 1  4 0 loads 4  5 60 loads 1  5 0 loads

Process Layout 1 2 3 4 5 Department 1 2 3 4 5 Load Summary Chart Example 5.1 1 2 3 4 5 Department 1 2 3 4 5 Load Summary Chart FROM/TO DEPARTMENT 1 — 100 50 2 — 200 50 3 60 — 40 50 4 100 — 60 5 50 — Composite Movements Composite Movements 2  3 200 loads 3  5 50 loads 2  4 150 loads 2  5 50 loads 1  3 110 loads 3  4 40 loads 1  2 100 loads 1  4 0 loads 4  5 60 loads 1  5 0 loads

Process Layout 1 2 3 4 5 Department 1 2 3 4 5 Load Summary Chart Example 5.1 1 2 3 4 5 100 200 150 50 60 40 110 Grid 1 Department 1 2 3 4 5 Load Summary Chart FROM/TO DEPARTMENT 1 — 100 50 2 — 200 50 3 60 — 40 50 4 100 — 60 5 50 — Composite Movements Composite Movements 2  3 200 loads 3  5 50 loads 2  4 150 loads 2  5 50 loads 1  3 110 loads 3  4 40 loads 1  2 100 loads 1  4 0 loads 4  5 60 loads 1  5 0 loads

Process Layout 1 2 3 4 5 Department 1 2 3 4 5 Load Summary Chart Example 5.1 1 2 3 4 5 100 200 150 50 60 40 110 Grid 2 Department 1 2 3 4 5 Load Summary Chart FROM/TO DEPARTMENT 1 — 100 50 2 — 200 50 3 60 — 40 50 4 100 — 60 5 50 — Composite Movements Composite Movements 2  3 200 loads 3  5 50 loads 2  4 150 loads 2  5 50 loads 1  3 110 loads 3  4 40 loads 1  2 100 loads 1  4 0 loads 4  5 60 loads 1  5 0 loads

Computerized Layout Solutions CRAFT - block diagramming CORELAP - relationship diagramming Simulation

Service Layouts Usually process layouts due to customers needs Minimize flow of customers or paperwork Retailing tries to maximize customer exposure to products Computer programs consider shelf space, demand, profitability Layouts must be aesthetically pleasing

Designing Product Layouts Product layouts or assembly lines Develop precedence diagram of tasks Jobs divided into work elements Assign work elements to workstations Try to balance the amount work of each workstation

Line Balancing Precedence diagram Cycle time Network showing order of tasks and restrictions on their performance Cycle time Maximum time product spends at any one workstation

Line Balancing Precedence diagram Cycle time example Cycle time Cd = Network showing order of tasks and restrictions on their performance Cycle time Maximum time product spends at any one workstation Cycle time example Cd = production time available desired units of output Cd = (8 hours x 60 minutes / hour) (120 units) Cd = = 4 minutes 480 120

Flow Time vs Cycle Time Cycle time = max time spent at any station Flow time = time to complete all stations

Cycle time = max (4, 4, 4) = 4 minutes Flow Time vs Cycle Time Cycle time = max time spent at any station Flow time = time to complete all stations 1 2 3 4 minutes Flow time = 4 + 4 + 4 = 12 minutes Cycle time = max (4, 4, 4) = 4 minutes

Minimum number of workstations Efficiency of Line  i i = 1 ti nCa E = Cd N = Efficiency Minimum number of workstations where ti = completion time for element i j = number of work elements n = actual number of workstations Ca = actual cycle time Cd = desired cycle time

Line Balancing Process 1. Draw and label a precedence diagram. 2. Calculate the desired cycle time required for the line. 3. Calculate the theoretical minimum number of workstations. 4. Group elements into workstations, recognizing cycle time and precedence constraints. 5. Calculate the efficiency of the line. 6. Stop if theoretical minimum number of workstations on an acceptable efficiency level reached. If not, go back to step 4.

Line Balancing

Line Balancing WORK ELEMENT PRECEDENCE TIME (MIN) A Press out sheet of fruit — 0.1 B Cut into strips A 0.2 C Outline fun shapes A 0.4 D Roll up and package B, C 0.3 Example 5.2

Line Balancing D B C A WORK ELEMENT PRECEDENCE TIME (MIN) A Press out sheet of fruit — 0.1 B Cut into strips A 0.2 C Outline fun shapes A 0.4 D Roll up and package B, C 0.3 0.1 0.2 0.4 0.3 D B C A Example 5.2

Line Balancing D B C A WORK ELEMENT PRECEDENCE TIME (MIN) A Press out sheet of fruit — 0.1 B Cut into strips A 0.2 C Outline fun shapes A 0.4 D Roll up and package B, C 0.3 0.1 0.2 0.4 0.3 D B C A Cd = = = 0.4 minute 40 hours x 60 minutes / hour 6,000 units 2400 6000 N = = = 2.5 workstations 1.0 0.4 0.1 + 0.2 + 0.3 + 0.4 Example 5.2

Line Balancing D B C A WORK ELEMENT PRECEDENCE TIME (MIN) A Press out sheet of fruit — 0.1 B Cut into strips A 0.2 C Outline fun shapes A 0.4 D Roll up and package B, C 0.3 0.1 0.2 0.4 0.3 D B C A Cd = = = 0.4 minute 40 hours x 60 minutes / hour 6,000 units 2400 6000 N = = = 2.5 workstations 1.0 0.4 0.1 + 0.2 + 0.3 + 0.4 3 workstations Example 5.2

Line Balancing D B C A WORK ELEMENT PRECEDENCE TIME (MIN) A Press out sheet of fruit — 0.1 B Cut into strips A 0.2 C Outline fun shapes A 0.4 D Roll up and package B, C 0.3 Cd = 0.4 N = 2.5 0.1 0.2 0.4 0.3 D B C A Example 5.2

Line Balancing D B C A REMAINING REMAINING WORKSTATION ELEMENT TIME ELEMENTS Cd = 0.4 N = 2.5 0.1 0.2 0.4 0.3 D B C A Example 5.2

Line Balancing D B C A REMAINING REMAINING WORKSTATION ELEMENT TIME ELEMENTS 1 A 0.3 B, C Cd = 0.4 N = 2.5 0.1 0.2 0.4 0.3 D B C A Example 5.2

Line Balancing D B C A REMAINING REMAINING WORKSTATION ELEMENT TIME ELEMENTS 1 A 0.3 B, C B 0.1 C, D Cd = 0.4 N = 2.5 0.1 0.2 0.4 0.3 D B C A Example 5.2

Line Balancing D B C A REMAINING REMAINING WORKSTATION ELEMENT TIME ELEMENTS 1 A 0.3 B, C B 0.1 C, D 2 C 0.0 D Cd = 0.4 N = 2.5 0.1 0.2 0.4 0.3 D B C A Example 5.2

Line Balancing D B C A REMAINING REMAINING WORKSTATION ELEMENT TIME ELEMENTS 1 A 0.3 B, C B 0.1 C, D 2 C 0.0 D 3 D 0.1 none Cd = 0.4 N = 2.5 0.1 0.2 0.4 0.3 D B C A Example 5.2

Line Balancing D B C A REMAINING REMAINING WORKSTATION ELEMENT TIME ELEMENTS 1 A 0.3 B, C B 0.1 C, D 2 C 0.0 D 3 D 0.1 none A, B C D Work station 1 Work station 2 Work station 3 0.3 minute 0.4 minute Cd = 0.4 N = 2.5 0.1 0.2 0.4 0.3 D B C A Example 5.2

Line Balancing D B C A REMAINING REMAINING WORKSTATION ELEMENT TIME ELEMENTS 1 A 0.3 B, C B 0.1 C, D 2 C 0.0 D 3 D 0.1 none A, B C D Work station 1 Work station 2 Work station 3 0.3 minute 0.4 minute 0.1 0.2 0.4 0.3 D B C A Cd = 0.4 N = 2.5 E = = = 0.833 = 83.3% 0.1 + 0.2 + 0.3 + 0.4 3(0.4) 1.0 1.2 Example 5.2