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LEAN MANUFACTURING PRINCIPLES. © NCSU IES LEAP Group Rev 3/04. The Connection. North Carolina State University Teaching, Research, Extension and Engagement College of Engineering Industrial Extension Service (IES). Industrial Extension Service.
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LEAN MANUFACTURING PRINCIPLES © NCSU IES LEAP Group Rev 3/04
The Connection • North Carolina State University Teaching, Research, Extension and Engagement • College of Engineering • Industrial Extension Service (IES)
Industrial Extension Service • Lean Enterprise Advancement Program (LEAP) • In-plant applications, manufacturing networks, public training, Shingo Prize • Advanced Performance and Standards (APS) • FORUMS, QS, ISO, Six Sigma, Project management, NC Awards for Excellence • Environmental, Health and Safety (EHS) • Training, technical assistance, needs assessment in ISO, HAZWOPER, HAZMAT, ergonomics and industrial hygiene • Energy and Facilities Management • Energy usage assessments
Lean Enterprise Advancement Program Mission - Improve the quality, cost and delivery of North Carolina manufacturing firms to improve their competitiveness by understanding and implementing lean enterprise business systems based on TPS model.
The LEAP mission is accomplished through - training facilitation manufacturing networks lean assessments
LEAN THINKING Key Principles of Lean Thinking • VALUE - what customers are willing to pay for • VALUE STREAM- the steps that deliver value • FLOW - organizing the Value Stream to be continuous • PULL - responding to downstream customer demand • PERFECTION - relentless continuous improvement (culture) --- Lean Thinking, Womack and Jones, 1996
Defining Lean Lean is: “A systematic approach to identifying and eliminatingwaste (non-value added activities) through continuous improvement by flowing the product at the pull of the customer in pursuit of perfection.” The MEP Lean Network
Lean Goals- TPS “True North” • Zero defects • 100% value-add • Lot size of one • Pull of the customer TSSC
LEAN MANUFACTURING Why Become Lean? • PQCDSM • Improve Customer Satisfaction • Increase Sales and Profits • Insure Long-term Health of Company • Survival • Create Sustainable Competitive Advantage
Percentage of Benefits Achieved 0 25 50 75 100 Typical Results from Lean Conversions Lead Time Reduction Productivity Increase WIP Reduction Quality Improvement Space Utilization Flexibility Skill Enhancement Visual Management
LEAN MANUFACTURING Where has Lean been successfully implemented? • Manufacturing • Automotive • Industrial Products • Furniture • Textiles and Apparel • Printing and Packaging • Consumer Products • Service Industries • Military • Healthcare
Developing a Lean Factory The Goal and Getting There from Here • The Goal - Lean Throughout the Entire Enterprise • Set Aggressive Improvement Goals • Measurements of Existing Operations • Recognize Current Problem Areas • Apply the Lean Production System Concepts • Commit to the Continuous Improvement Process • Just do it!
Value Added/Non-value Added • Value-added: • ANY ACTIVITY THAT PHYSICALLY CHANGES THE MATERIAL BEING WORKED ON (not rework/repair!) • Machining Knitting • Drilling Spreading/Cutting • Assembly Dying • Painting Sewing • Non-value added: • ANY ACTIVITY THAT TAKES TIME, MATERIAL, OR SPACE BUT DOES NOT PHYSICALLY CHANGE THE MATERIAL • Sorting Stacking • Counting Checking
Value added 5% Non-value added Typically 95% of Total Lead Time is Non-Value Added!!! Lean = Eliminating the waste 8 Wastes • Overproduction • Excess inventory • Defects • Non-value added processing • Waiting • Underutilized people • Excess motion • Transportation
Value Stream Mapping A simple diagram of every step involved in the material and information flows needed to bring a product from order to delivery. Value stream maps can be drawn for different points in time as a way to raise consciousness of opportunities for improvement. - Lean Lexicon
Lean Production System Goals - highest quality, lowest cost, shortest lead times • Just-In-Time • continuous flow • takt time/pace • pull system • triggers • Jidoka • separate man & • machine work • identify abnormal • conditions • poka yoke Involvement Heijunka Standardized Work Kaizen Stable Manufacturing Process
Toyota’s Philosophy • Customer first • People are the most valuable resource • Kaizen (continuous improvement) • Shop floor focus
Lean Production System Goals - highest quality, lowest cost, shortest lead times • Just-In-Time • continuous flow • takt time/pace • pull system • triggers • Jidoka • separate man & • machine work • identify abnormal • conditions • poka yoke Involvement Heijunka Standardized Work Kaizen Stable Manufacturing Process
Stability The Four Ms • Operations safely carried out with all task organized in the best known sequence and by using the most effective combination of resources • huMans • Materials • Methods • Machines
Stability The 5S’s • Sort • Keep only what is needed in your area • Stabilize • A place for everything and everything in its place • Shine • Clean up the workplace • Standardize • Develop system (rules) to maintain what has been done • Sustain • Self discipline to maintain established procedures
Stability The 5S’s - Before
Stability The 5S’s
Stability The 5S’s Courtesy of National Textiles
Stability Visual Controls • Visual Controlsare simple signals that provide an immediate understanding of a situation or condition. They are efficient, self regulating, and worker managed. Examples include: • Pictures, diagrams • Color coded dies, tools, pallets • Lines on the floor to delineate storage areas, walk • ways, work areas, etc. • Improved lighting
Stability Visual Controls
Stability Plant Layout Shipping Q C Receiving Raw Stock Q C Screw Machine Shear Stamp Drill Lathe Assembly Brake Mill Weld Grind Finish Parts Stock
1 2 3 4 5 Lathe Drill Mill Mill Inspect 27 Seconds 27 Seconds 6 27 Seconds Drill 10 9 8 7 Pack Inspect Drill Test Stability Cellular Layout Market Demand = 220,000 Units Per Year Takt Time = 27 Seconds
Stability Cellular Layout Courtesy of Duff-Norton, Charlotte, NC
Stability Total Productive Maintenance • Total Productive Maintenance (TPM)is a series of methods to keep equipment running • The goals of the TPM process include: • Develop people who are equipment-knowledgeable • Create well-engineered equipment: building in safety and quality • Create an environment where enthusiasm and creativity flourish • Maximize equipment productivity and capacity as measured by Overall Equipment Effectiveness (OEE)
Stability OEE = Availability × Performance Efficiency × Rate of Quality Rate of Quality Do you manufacture quality products? Are your processes repeatable? Availability When or how often do you lose total availability of your equipment? How long are your set-ups? Does your equipment break down frequently? Performance Efficiency Does your equipment start and stop a lot? Does your equipment run at 100% of its designed speed? The Six Big Losses that downgrade Machine Effectiveness: • Related Losses • Setup and Adjustment • Breakdowns • Related Losses • Idling and Minor Stoppages • Reduced Speed • Related Losses • Startup • Defects and Rework
Sample Daily Operator PM Daily Operator PM 1. Check coolant level through clear Plexiglas 2. Check heat exchanger fans(strings should be moving) 3. Check servo drive fans (string should be moving) 4. Check heat exchanger air filter(change when dark) 5. Check servo drive air filter(change when dark) 6. Check way lube reservoir(add when low) 7. Check main motor air filter(change when dark) 8. Check main motor cooling fan(string should move) 9. Check mist collector motor and air filter(change when dark) 10. Check bar feeder hydraulic motor air filter 11. Check bar feeder hydraulic oil level(add when low)
Developing a Lean Factory Summary – Stability in Manufacturing Processes • 4Ms • 5S • Visual Controls • Plant Layout • Total Productive Maintenance
Lean Production System Goals - highest quality, lowest cost, shortest lead times • Just-In-Time • continuous flow • takt time/pace • pull system • triggers • Jidoka • separate man & • machine work • identify abnormal • conditions • poka yoke Involvement Heijunka Standardized Work Kaizen Stable Manufacturing Process
Just-in-Time Pull System • Pull System is a flexible and simple method of controlling/balancing the flow of resources. • Eliminating waste of handling, storage, expediting, obsolescence, repair, rework, facilities, equipment, excess inventory (work-in-process and finished). • Pull System consists of: • Production based on actual consumption • Small Lots • Low inventories • Management by Sight • Better Communication
Just-in-Time Pull System • Kanban • - A signal to indicate when more parts are needed • (Order or Produce) • - Card, empty Bin, In Process Kanban (IPK) on plant floor
Just-in-Time Pull System Courtesy of Ingersoll-Rand Co., Southern Pines, NC
Just-in-Time Supermarket Analogy • A carton of milk is removed from shelf • A stock person restocks the empty location, • but only brings what shelf can accommodate • the supermarket combines visual control, pull system, • Kanban, 5S
Just-in-Time Quick Changeover (Set-up Reduction) • Single Minute Exchange of Dies (SMED) • a series of techniques for changeovers of production machinery in less than ten minutes (single digit minutes) • Set-up Reduction Program Goals • To achieve smaller lots • To maintain consistent quality • To minimize inventory • To reduce lead times • To address frustration of setup personnel
Just-in-Time Basic SMED Principles • Identify internal vs. external changeover tasks • Analyze each task’s real purpose and function • Focus on no/low cost solutions • Aim to eliminate changeover time
Just-in-Time Positioning Pins Positioning Pins
Just-in-Time No/Low Cost Solution: One-Turn Methods Pear-Shaped Hole Method Tighten Here Attach and Remove Here
Just-in-Time No/Low Cost Solution: One-Turn Methods Speed Nut
Just-in-Time No/Low Cost Solution: One-Turn Methods Wing Nut Method
Just-in-Time No/Low Cost Solution: One-Motion Methods Cam Method
Just-in-Time Quick Changeover Not quick: Must heat molds and plates before changeover Quicker: Test stand with hot plates to pre-heat molds and plates Courtesy of Playtex Panama, Santo Domingo, DR
Just-in-Time Continuous Flow - Batch Size Reduction • The best batch size is one - one piece flow, or make one and move one! • Benefits: Reduces WIP, lead time, cycle time, etc. and improves quality
Process Process A B • Continuous Flow Processing Process Process Process A B C 12 min. for total order 3 min. for first part Just-in-Time • Batch & Queue Processing Process C 10 minutes 10 minutes 10 minutes Lead Time: 30+ minutes for total order 21+ minutes for first piece
Takt Time = Just-in-Time Takt Time = Demand Rate WorkTime Available Number of Units Sold GOAL: Produce to Demand
Developing a Lean Factory Summary - Just-in-Time • Pull Systems/Kanban • Point Of Use Storage • Quick Changeover/Setup Reduction • Continuous Flow • Takt Time