JIT TPS and Lean Chapter 16 JIT TPS

JIT, TPS and Lean Chapter 16

JIT, TPS, Lean • The purpose of all these approaches is to eliminate waste, reduce variability, and improve throughput! • JIT (Just In Time) • Focus is on “forced problem solving” rather than covering it up • TPS (Toyota Production System) • Focus is on employee learning and empowerment • Lean • Focus is on understanding the customer and eliminating activities that don’t contribute value to them

Eliminate Waste • Waste is any activity that does not add value to the customer • Seven Categories of Waste Five Ss • • Overproduction Queues Transportation Inventory Motion Overprocessing Defects - Sort/Segregate - Simplify/Straighten - Shine/Sweep - Standardize - Sustain/Self-Discipline - *Safety - *Support

Remove Variability • Variation is any deviation (natural or artificial) from the optimum process that delivers the product on time every time. • It is often tolerated by management, but must not be! • Sources Include • Unknown Demand • Processes that allow employees to produce non-conforming units • Inaccurate drawings, incomplete product plans, specs • Variability may be “hidden”, by large inventories, etc

Improve Throughput • Throughput – rate at which goods move through a production process • “push” system – produces orders regardless of demand • “Pull” system – delivers material when and where it is needed • Both for suppliers and on factory floors • Uses signals to request when stations have capacity available • Pulls only the necessary amount

Just In Time (JIT) • Produce material when they are needed, where they are needed • If a unit doesn’t arrive, then it is a “problem” • Any problems become “visible” • No padding from inventory • No slack time

JIT Partnerships • Supplier and buyer collaborate to eliminate problems, unnecessary activities, inventory reduction, increase reliability • Scan in fig 16. 2

JIT Layout Tactics • Aim is to eliminate wasteful movement (goods, parts, people, etc) • Reduce distance • Work cell arrangement, etc • Increase Flexibility • Adapt to changes in volume, configuration, etc • Tactics with Employees • Cross-trained, communication of problems and feedback • Reduce space and inventory • Keep units moving downstream • Less need for storage space • Deliver to where goods are needed

JIT Inventory Tactics • Reduce inventory and lot sizes. • They can cover up problems, therefore it should be eliminated • Scan in fig 16. 3 and 16. 4 • Reduce setup costs • “one-touch” systems, training, materials, checklists, monitoring

JIT Scheduling Tactics • Communicate schedule to suppliers • Make level schedules • Frequent small batches as opposed to infrequent large • “freezing” the schedule close to delivery date • Kanban • Japanese word for “card” (but in reality could be a container, empty floor, etc) • Signal for demand from downstream to upstream • Scan in figure 16. 8

Quality Tactics • Measure! Use data collection and statistics to control processes • Empower employees • Build failsafe methods • Provide immediate feedback • Kaizen “change for the good” • Incremental changes • Standardize work processes

Quality Improvement with Six Sigma Define Control Improve Measure Analyze

How to build a “lean” organization • Use JIT tactics to eliminate inventory • Build systems to help employees produce perfect products • Reduce space requirements • Develop partnerships with suppliers • Educate suppliers about the end customer needs • Eliminate all but value added activities • Develop and challenge employees