Just-In-Time “Eliminate Waste”
Flexible Resources Multifunctional workers General-purpose machines Operate more than one machine General-purpose machines Machines that were not highly specialized
Cellular Layouts Manufacturing cells Often U-shaped Work flows through cell in one direction and experiences little waiting
Pull System Coordinating production and delivery of materials and parts Traditionally, inventory has been used as a cushion against lapses in coordination and inventory can be huge Pull system observed at US supermarkets Marina Safeway example
Pull System Do not order more product than can be used (or items that can be sold) Reversal of normal ‘push’ system
Kanban Production Control System Japanese word for ‘card’ Associated with fixed-quantity inventory system Two-bin system Kanban
Small-Lot Production Requires less space and capital Produces small amounts at a time Processes can be moved closer together Transport between stations is simplified Quality problems are easier to detect Reveals errors and bottlenecks HP video
Lead Time Processing time Move time Can be reduced by reducing number of items processed and the efficiency or speed of the worker Move time Can be decreased if machines are moved closer together, method of movement simplified, routings are standardized, or need for movement eliminated Con’t
Lead Time Waiting Time Setup Time Can be reduced through better scheduling of materials, workers, machines and sufficient capacity Setup Time Reduction of setup time is important to JIT
Quick Setups Separate internal setup from external setup Internal setup requires the machine to be stopped External setup can be done while machine is running Convert internal setup to external setup Prepare as much as possible in advance (preheating injection mold, standardizing die heights, centering die, etc)
Quick Setups Streamline all aspects of setup Organize workplace properly locating tools near points of use Keep machines and fixtures in good repair Simplify or eliminate adjustments precoding desired settings, using locator pins, etc. Perform setup activities in parallel or eliminate Add a person, standardize components, parts, materials
Uniform Production Levels Smoothing production requirements on the final assembly line Better forecast Mixed production throughout the day in small quantities
Quality at the Source For JIT to work, quality has to be high No extra inventory to buffer against defective units Producing poor-quality items and reworking items or rejecting them is wasteful Workers are responsible for inspection NEVER pass along defective item
Quality at the Source Jidoka Andons Undercapacity scheduling Authority to stop production line if quality problems were encountered Andons Call lights activated by switches Undercapacity scheduling Making time to plan, train, solve problems, maintain work environment
Quality at the Source Visual control Quality improves when problems are made visible and workers have clear expectations of performance Kanbans, andons, process control charts, tool boards, material handling routes clearly marked, demos, instructional photos, performance data
Quality at the Source Poka-yoke Kaizen Foolproof device or mechanism that prevents defects from occurring Kaizen Continuous improvement
Total Productive Maintenance Breakdown maintenance Preventive maintenance Total Productive Maintenance Accurate records on time between breakdowns Frequency of breakdowns Costs of breakdowns Determine a preventive maintenance schedule Employee involvement Zero defects
Supplier Networks Working with suppliers to improve responsiveness and quality Trends: Locate near the customer Use small, side-loaded trucks and ship mixed loads Consider establishing small warehouses near to the customer Use standardized containers and make deliveries according to a precise delivery schedule Become a certified supplier and accept payment at regular intervals rather than upon delivery
Benefits of JIT Reduced inventory Improved quality Lower costs Reduced space requirements Shorter lead time Increased productivity
Benefits of JIT Greater flexibility Better relations with suppliers Simplified scheduling and control activities Increased capacity Better use of human resources More product variety