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Readings

Readings. “Even in a topsy-turvy world, just-in-time supply works,” by James P. Womack and Daniel T. Jones. Automotive News , Oct. 29, 2001. “Lean Time, Lean Measures,” by Michael San Filippo, January/February 2002 Interview.

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Readings

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  1. Readings • “Even in a topsy-turvy world, just-in-time supply works,” by James P. Womack and Daniel T. Jones. Automotive News, Oct. 29, 2001. • “Lean Time, Lean Measures,” by Michael San Filippo, January/February 2002 Interview. • “Building the Lean Machine,” Advanced Manufacturing, January 2000. • Chapter 18 of Computer Aided Manufacturing, Wang, H.P., Chang, T.C. and Wysk, R. A., 3rd Edition (2004 expected) http://www.engr.psu.edu/cim/active/chapter18.pdf

  2. ExerciseReadiness Assessment Test A.K.A. RAT AS A INDIVIDUAL, look at the detailed requirements for a production process. We will look at the Case Study and Key holder. • What is the operation time for the Key holder at each workstation in a production system? • How is this time related to the time required to produce a key holder? • What is the difference between production time and setup time? Open Book / Open Notes

  3. ExerciseReadiness Assessment Test A.K.A. RAT AS A TEAM, take 3 minutes to provide a written to answer the following questions: • Did all operations require the same time? • What is best operation to focus attention of for the key holder? • Why? Closed Book / Closed Notes

  4. Objectives • To apply the principles of flow to a complex manufacturing system • To design the layout of process, product and cellular manufacturing systems • To implement a pull system in a manufacturing environment • To analyze efficiencies of reduced batch sizes

  5. Exercise (3 – 5 minutes) • Individually answer the following questions • What percent of time does a part spend having “value added” to it while the part is on the shop floor? • What are the top 5 causes of “non-value added” times?

  6. Quick Change Over QCO is used to: • Reduce time needed to change over from one set-up to another. • Improve first time capability. • Improve repeatability of change over operations

  7. Total Productive Maintenance • TPM is a structured approach to maintaining equipment and insuring stable manufacturing processes. • Everybody gets involved.

  8. What to Expect in the Future • Training • Communication • Elimination of Waste (NVA) • Continuous Improvement • Visual Factory • More efficient layouts • Roles & Responsibilities • More involvement / ownership • Long term GROWTH!!

  9. Types of Manufacturing Layout • Process Layout • Product Layout • Cellular Layout

  10. FUNCTIONAL LAYOUTS ARE INEFFICIENT Drilling Milling Lathe D D L M L M D D L L M M Grinding G L L M G M Assembly G G L L A A G G A Receiving and Shipping A PROCESS-TYPE LAYOUT

  11. Process Layout Characteristics • Advantages • Deep knowledge of the process • Common tooling and fixtures • Most Flexible -- can produce many different part types • Disadvantages • Spaghetti flow -- everything gets all tangled up (can not “pull” materials with this layout) • Lots of in-process materials • Hard to control inter-department activities • Can be difficult to automate

  12. L G G L M PRODUCT LAYOUT G D Part #1 M L A A Receiving Part #2 D M L Shipping Part #3

  13. Product Layout Characteristics • Advantages • Easy to control -- input control • Minimum material handling -- frequently linked to the next process • Minimal in-process materials • Can be more easily automated • Disadvantages • Inflexible -- can only produce one or two parts • Large setup • Duplicate tooling is required for all cells

  14. CELLULAR LAYOUT Cell #2 Cell #1 D D M I D I L Cell #3 M M L D L I M

  15. Cellular Layout Characteristics • Advantages • Control is simplified • Common tooling and fixtures • Flexible -- can produce many different part types - a part family?? • Disadvantages • Setup ?? • Need to know about many different processes

  16. Evidence of Progress toward Lean • Smaller lot sizes • Increased capacity / throughput • Higher inventory turns • More available floor space • Improved workplace organization • Improved quality : reduced scrap / re-work • Reduced inventories : raw, WIP, FG • Reduced lead times • Greater gross margin • Improved participation & morale

  17. Lean Mfg Implementation Timeline • LMA – 6 to 12 weeks • (Prototype line/experimentation?) • Management commitment – 4 to 6 months • Prep for implementation – 6 to 8 months • Model line development – 6 months to 1 year • Program expansion – 1 to 3 yrs • Beginnings of the ‘Lean Enterprise’ – 3 to 5 yrs

  18. 3 3 2 2 1 1 Price Increase Price to Sell Bigger Profit Some Profit Cost to Produce Cost + Profit = Price

  19. 1 1 3 3 2 2 Cost Reduction Price to Sell Some Profit Bigger Profit Cost to Produce Price - Cost = Profit

  20. Storing Counting Sorting Moving What value is Added by: Acknowledgments Invoices Expediting Rework Inspecting Loading / Unloading Scrap Returns to Suppliers Receiving Report Repackaging

  21. Toyota Production System Best Quality - Lowest Cost - Shortest Lead TimeThrough shortening the Production Flow by Eliminating Waste Just in Time“The right partat the right timein the right amount” Jidoka“Built in Quality” • Manual / Automatic Line Stop • Labor-Machine Efficiency • Error Proofing • Visual Control • Continuous Flow • Pull System • Level Production (Heijunka) Flexible, Capable,Highly Motivated People Operational Stability Standardized Work Total Productive Maintenance Robust Products & Processes Supplier Involvement

  22. Just in Time Manufacturing Produce according to customer demands: • What is needed • When it is needed • In the quantity it is needed Utilize - Continuous flow processing - Pull system

  23. Push System Lot arrival triggers production Material Information MRP Schedule triggers Production Example: MRP

  24. Pull Systems Material Withdrawal of material triggers production Information Production schedule is issued only to final assembly line. Production schedule for each of the preceding process is determined by transfer of parts Parts are pulled through the system from the end of the line to the start

  25. Parts are produced only when needed (or just in time) • less delay or lead time, lower inventory • KANBAN - is the manual system to implement the pull system • JIT - refers to the whole system, the material flow and management philosophy

  26. JIT Systems • Combines both the production control component and a management philosophy • 4 basic tenets for the success of JIT • Elimination of waste • Employee Involvement • Supplier Participation • Total Quality Management

  27. Kanban • Manual information system to control production. Material transportation, and inventory • Literally means “visible record” or card • In the the broad sense it is a communication signal from a downstream process (customer) to a upstream process (producer)

  28. Kinds of Kanban • Two most common kanbans • production kanbans (P- Kanban) • authorizes a process to produce a fixed amount of product

  29. Kanban continued • Transportation kanban (T- Kanban) • authorizes transporting a fixed amount of product downstream

  30. JIT Element - Continuous Flow Processing Batch Processing 10 minutes 10 minutes 10 minutes Total Batch A processing time : 30 minutes Continuous Flow Processing Total Batch A processing time : 12 minutesOnly 3 minutes for 1st part • Product requires three processes that take one minute each • Processing first batch in batches of 10 requires 30 minutes • Processing first “batch” one-at-a-time requires only 12 minutes

  31. A B C D E F G H I J K L M N O P Q Store JIT Element - Pull System • Following processes withdraw what they need when they need it. • Preceding processes replenish what is taken away. Production Kanban Withdrawal Kanban Upstream Processes Downstream Processes Pull New Product Needed Product

  32. Production Scheduling Assumptions • Production Schedules will always change • Production will never go according to schedule.

  33. Takt time Takt time - takt, is a German term for rhythm. Takt time is the allowable time to produce one product at the rate customers are demanding it. This is NOT the same as cycle time, which is the normal time to complete an operation on a product (which should be less than or equal to takt time).

  34. Takt Time Time (Available seconds per working day) = Takt Time Volume (Daily production requirement) Sets pace of production to match pace of sales. Actual time required for a worker to complete one cycle of his process = Cycle Time

  35. Takt Time (1 min.) 1 min. Cycle Time Operators A B C D E Takt Time (1 min.) 1 min. Operators A B C D E Balanced Cycle Times

  36. Left Hand Left Hand change over change over Right Hand change over Right Hand Left Hand change over Right Hand change over change over Left Hand Left Hand change over Right Hand change over change over Left Hand Right Hand change over Right Hand change over change over Very Frequent Change-over 8 hours

  37. Building in Quality JIDOKA Machines intelligence to be self-operating and self-stopping People served by machines, not vice versa Quality built-in, not inspected-in Efficiency human work separated from machine work, people freed to do value-added work

  38. Quality Processes Yield Quality Results Inconsistent Process Inconsistent Results Traditional = People doing whatever they can to get results Consistent Process Desired Results Lean = People using standard process to get results

  39. Impact on You!! First Time Quality • Standardized Work • Error Proofing • Root Cause Analysis • Problem Solving • Change Request Forms • Predictable Processes • Machine Reliability • Total Productive Maintenance • Improved up-time • Reduced scrap & repairs • People • Skilled, multi-function workers • Training • Employee development • Small Group Activity • Quality • Safety • Productivity • Cost • Structured feedback meetings • Empowerment • Involvement • Accountability • Responsibility • Authority • Safety & Ergonomics • Just in Time • Kanban production • Min / Max levels • Smaller Lots • Quick Change Over • Less inventory • Less reliance on schedules

  40. Exercise – (3 – 5 minutes) • As a group, discuss a situation that you are familiar with where continuous flow would improve a systems performance. • Is this flow limited to manufacturing? • Prepare to respond to the entire class?

  41. Questions?There are no stupid questions!

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