Transcript Chapter 11
Chapter 15 Just-In-Time Systems © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e What is JIT ? Producing only what is needed, when it is needed A philosophy An integrated management system. JIT’s mandate: Eliminate all waste. © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 2 2 Inventory Hides Problems Bad Design Lengthy Setups Inefficient Layout © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e Poor Quality Machine Breakdown Unreliable Supplier 2000 by Prentice-Hall, Inc Ch 15 - 22 3 Examples of Waste Watching a machine run Waiting for parts Counting parts Overproduction Moving parts over long distances Storing inventory Looking for tools Machine breakdown Rework © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 4 4 Basic Elements of JIT 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Flexible resources Cellular layouts Pull production system Kanban production control Small-lot production Quick setups Uniform production Quality at the source Total productive maintenance Supplier networks © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 3 5 Flexible Resources Multifunctional workers General purpose machines Study operators & improve operations © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 5 6 Manufacturing Cell With Worker Routes Machines Enter Worker 2 Worker 3 Worker 1 Exit Key: © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e Product route Worker route 2000 by Prentice-Hall, Inc Ch 15 - 8 7 Cellular Layouts Group dissimilar machines in manufacturing cell to produce family of parts Work flows in one direction through cell Cycle time adjusted by changing worker paths © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 7 8 Kanban Production Control System Kanban card indicates standard quantity of production Derived from two-bin inventory system Kanban maintains discipline of pull production Production kanban authorizes production Withdrawal kanban authorizes movement of goods © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 10 9 A Sample Kanban Part no.: 7412 Description: Slip rings From : Machining M-2 © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e Box capacity 25 Box Type A Issue No. 3/5 2000 by Prentice-Hall, Inc To: Assembly A-4 Ch 15 - 11 10 Small-Lot Production Requires less space & capital investment Moves processes closer together Makes quality problems easier to detect Makes processes more dependent on each other © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 21 11 Reducing Setup Time Preset desired settings Use quick fasteners Use locator pins Prevent misalignments Eliminate tools Make movements easier © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 25 12 Uniform Production Results from smoothing production requirements Kanban systems can handle +/10% demand changes Smooths demand across planning horizon Mixed-model assembly steadies component production © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 26 13 Quality At The Source Jidoka is authority to stop production line Andon lights signal quality problems Undercapacity scheduling allows for planning, problem solving & maintenance Visual control makes problems visible Poka-yoke prevents defects © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 28 14 Kaizen Continuous improvement Requires total employment involvement Essence of JIT is willingness of workers to spot quality problems halt production when necessary generate ideas for improvement analyze problems perform different functions © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 29 15 Total Productive Maintenance (TPM) Breakdown maintenance Preventive maintenance repairs to make failed machine operational system of periodic inspection & maintenance to keep machines operating TPM combines preventive maintenance & total quality concepts © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 30 16 TPM Requires Management To Design products that can be easily produced on existing machines Design machines for easier operations, changeover, maintenance Train & retrain workers to operate machines Purchase machines that maximize productive potential Design preventive maintenance plan spanning life of machine © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 31 17 Trends In Supplier Policies 1. Locate near to customer 2. Use small, side loaded trucks and ship mixed loads 3. Consider establishing small warehouses near to the customer or consolidating warehouses with other suppliers 4. Use standardized containers and make deliveries according to a precise delivery schedule 5. Become a certified supplier and accept payment at regular intervals rather than upon delivery © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 33 18 Benefits Of JIT 1. Reduced inventory 2. Improved quality 3. Lower costs 4. Reduced space requirements 5. Shorter lead time 6. Increased productivity © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 7. 8. Greater flexibility Better relations with suppliers 9. Simplified scheduling and control activities 10. Increased capacity 11. Better use of human resources 12. More product variety 2000 by Prentice-Hall, Inc Ch 15 - 34 19 JIT Implementation Use JIT to finely tune an operating system Somewhat different in USA than Japan – why? JIT is still evolving JIT isn’t for everyone © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 35 20 JIT In Services Competition on speed & quality Multifunctional department store workers Work cells at fast-food restaurants Just-in-time publishing for textbooks Construction firms receiving material just as needed © 2000 by Prentice-Hall Inc Russell/Taylor Oper Mgt 3/e 2000 by Prentice-Hall, Inc Ch 15 - 36 21