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Copyright © 2009 Art of Lean, Inc.
Fundamentals of Lean Production
Creating Stability in the 4M’s
Author: Art Smalley
Copyright © 2006 Art of Lean, Inc.
The need for stability
Process Process Process
Customer
Ideal!
Availability 100%
Quality 100%
C/O Flexibility 100%
Of course an ideal process would have no problems but who has that
situation in their facility?
Reality!
Availability 70%
Quality 93.5%
C/O Time = 1 hour
Copyright © 2006 Art of Lean, Inc.
Question
• What type of instability do you face in your facilities?
Copyright © 2006 Art of Lean, Inc.
Sample answers
• What type of instability do you face in your facilities?
Sample past answers
-Machine breakdowns
-Varying work methods
-Quality problems
-Employee turnover
-Lack of material when needed
-Process instability
-Many others as well
Conclusion: This can be a major problem for anyone attempting to improve!
Copyright © 2006 Art of Lean, Inc.
4M Framework*
Problemsin anyProductionProcess
ManMachine
MethodMaterial
*Can of course be expanded to include Measurement, Environment, etc. as needed
Copyright © 2006 Art of Lean, Inc.
Sufficientstability
MethodMaterial
Machine
Man
Key points we’ll discuss…
Copyright © 2006 Art of Lean, Inc.
Why is manpower sometimes a form of instability?
Copyright © 2006 Art of Lean, Inc.
Sample Answers
•Sometimes not enough (or sometimes too many!) resources areassigned to the job
•Sometimes people are not trained sufficiently in how to do the job
•Often people don’t get along with each other
•There are poor methods for documenting jobs, training people, andmaking small improvements
•Supervisors don’t have the right set of skills to effectively manage thesituation
•Other reasons.
Believe it or not but Toyota had all of these problems in the1950’s. One of their first priorities was to improve first linesupervisor skill sets in the plant
Copyright © 2006 Art of Lean, Inc.
1. Knowledge of work-(e.g. how we do things)
2. Knowledge of responsibility-(e.g. what we need to do by when)
3. Skill in improvement-(e.g. how can we do this better)
4. Skill in leadership-(e.g. why we do things this way)
5. Skill in teaching-(how to pass along our skills to others)
Toyota’s expectations of a leader in manufacturing
Copyright © 2006 Art of Lean, Inc.
TWI 3J Courses
• JI
• JR
• JM
How do people in companies typicallylearn today?
Copyright © 2006 Art of Lean, Inc.
How to teach an employee to do a particular job
-Safely
-Correctly
-Conscientiously
JI Motto –
If the employee has not learned,then the instructor has not taught!
JI Training Goal
Copyright © 2006 Art of Lean, Inc.
1. Telling-Explaining verbally
2. Showing-Demonstrating how it is done
3. Illustrating-Explaining with written material or pictures
4. Question & Answer-Asking about and discussing the contents
Typical teaching methods…
Each of these methods used in isolation has inherent flawswhich can be demonstrated during a JI training session.However, the four ways used together in a standard manner canbe a highly effective method for transferring basic knowledge
Copyright © 2006 Art of Lean, Inc.
JI Ineffective Teaching Demonstration
Copyright © 2006 Art of Lean, Inc.
JI Effective Teaching Demonstration
Copyright © 2006 Art of Lean, Inc.
JI Basic Major Steps
Step 1: Prepare the learner
Step 2: Present the operation
Step 3: Try out the operation
Step 4: Follow Up
Copyright © 2006 Art of Lean, Inc.
Job Instruction Basic Teaching Pattern
Major Steps
Major Steps + Key Points
Major Steps + Key Points + Reasons Why
Silently
Major Steps
Major Steps + Key Points
Major Steps + Key Points + Reasons Why
2. Present
3.Try out
4. Follow up
Trainer
Learner
1. Prepare
Copyright © 2006 Art of Lean, Inc.
•Put the learner at ease
•State the job
•Find out what they already know
•Get the team member interested in learning
•Put the learner in the correct position
Create an informal atmosphere conducive to learning.Motivate the learning to master the contents.
Step 1: Prepare the Learner
Copyright © 2006 Art of Lean, Inc.
1. Instructor does the job and describes the operationone Major Step at a time
2. Instructor does the job, states the Major steps, andstresses each Key Point
3. Instructor does the job, states the Major Steps, KeyPoints, and explains the Reasons
Instruct clearly, completely, patiently.Present only what the learner can master
Step 2: Present the Operation
Copyright © 2006 Art of Lean, Inc.
4. Learner does the job silently. Instructor correctserrors as needed.
5. Learner does the job - explains each Major Step
6. Learner does the job - explains the Major Steps,& Key Points behind each step
7. Learner does the job - explains the Major Steps,Key Points, & Reasons Why
The learner demonstrate the operation 4 timesfor a combined total of 7 repetitions overall
Step 3: Try out the Operation
Copyright © 2006 Art of Lean, Inc.
• Put learner on own
• Encourage questions by the learner
• Designate for whom to go for help
• Check back frequently at first
• Taper off and provide coaching as needed
If the employee has not learned, the instructorhas not taught!
Step 4: Follow Up
Copyright © 2006 Art of Lean, Inc.
• Level 1 – Can they do the job safely and correctly?
• Level 2 – Can they do the job also to takt time (pace)?
• Level 3 – Have they done the job over an extended period of time
with no problems?
• Level 4 – Can they use JI methods to train others?
Evaluation
Copyright © 2006 Art of Lean, Inc.
TWI 3J Courses
• JI
• JR
• JM
What is a good supervisor?
Copyright © 2006 Art of Lean, Inc.
SUPERVISOR
Job Relations
ManagerPeer group from
other departments inthe plant
Other parties(engineers,
administrative staff,etc.
Customers internaland external
Union or shoprelated parties
Training Production
Cost
SafetyQuality
Maintenance
DeliveryPeople
Copyright © 2006 Art of Lean, Inc.
A supervisor getsresults through people
SUPERVISOR
Training Production
Cost
SafetyQuality
Maintenance
DeliveryPeople
Job Relations
Foundations forgood relations
1. Let each worker knowhow he or she isperforming.
2. Give credit when due.Recognize andreward.
3. Tell people inadvance aboutchanges that affectthem.
4. Make best use ofeach person’s ability.
People must betreated as individuals
Health
Background
Family
Job
Individual
OtherEducation
Copyright © 2006 Art of Lean, Inc.
The primary concept behind JR is that a supervisor gets resultsthrough people. Good relations = Good results!
Job Relations (JR) Intro
Foundations for Good Relations
•Let each worker know how he or she is doing-Figure out what you expect from him-Point out ways to improve
•Give credit when due-Look for extra or unusual performance-Tell him while it is still fresh
•Tell people in advance about changes that affect them-Tell them why if possible-Get them to accept change
•Make the best use of each person’s ability-Look for ability not now being used-Never stand in a person’s way
People must be treated as individuals!
ProactiveDimensions
Copyright © 2006 Art of Lean, Inc.
How to handle a job relations problem (2-3 case studies)
JR – 4 Steps
Determine the objective
1. Get the facts
2. Weigh and decide
3. Take action
4. Check results
ReactiveDimensions
Copyright © 2006 Art of Lean, Inc.
JR Discussion Worksheet
1. Get the facts 2. Weigh and decide 3. Take action 4. Check results
1. When to follow up?2. How often?3. Did it help?4. Effect on output,
attitude, & relationship
1. Fits the facts together2. What possible actions?3. Check policies4. Consider effect on
individual, group, &company
1. Review record2. Check with others3. Get the whole story4. Obtain feelings5. Get whole story
1. Handle yourself?2. Need any support?3. Verify policies4. Watch timing5. Don’t put it off
Objective:
Copyright © 2006 Art of Lean, Inc.
Question on Supervisor – Team Problems
Copyright © 2006 Art of Lean, Inc.
TWI 3J Courses
• JI
• JR
• JM How do you improve work?
Copyright © 2006 Art of Lean, Inc.
•JM is a practical method to help you produce greater quantities ofquality products in less time, by making the best use of manpower,machines, and materials now available
Job Methods (JM) Intro
JM consists of 4 main steps
1. Step I – Break down the job
2. Step II – Question every detail
3. Step III – Develop the new method
4. Step IV – Apply the new method
Copyright © 2006 Art of Lean, Inc.
JM Step 1 – Break down the job
1. List all the details of the job exactly as done by the present method
2. Be sure to details include all:
a. Material handling
b. Machine work
c. Hand work
Copyright © 2006 Art of Lean, Inc.
Sample JM Sheet For Work Analysis
Operation: Product: Department:
Date:Name:
No. Work Elements ConsiderationPoints*
Why
What
Where
When
Who
How
Ideas (E, C, R, S)
*Safety, Distance, Dimensions, Quality, Ease, etc.
Copyright © 2006 Art of Lean, Inc.
JM Step 2 – Question every detail
1. Use these types of questions:
a. Why is it necessary?
b. What is its purpose?
c. Where should it be done?
d. When should it be done?
e. Who is best qualified to do it?
f. How is the best way to do it?
2. Also question the materials, machines, product design, layout, workplace, safety, and house keeping
Copyright © 2006 Art of Lean, Inc.
JM Step 3 – Develop the new method
1. Eliminate unnecessary details
2. Combine details when practical
3. Rearrange for better sequence
4. Simplify all necessary details
a. Make the work easier
b. Pre-position materials, tools, and equipment at the best places inthe proper work area
c. Use gravity feed hoppers and drop chute delivery
d. Let both hands do useful work
e. Use jigs and fixtures instead of hands for holding work
5. Work out your ideas with other
6. Write up your proposed new method
Copyright © 2006 Art of Lean, Inc.
JM Step 4 – Apply the method
1. Sell your proposal to the persons necessary
2. Sell the new method to the operators (involve them is best!)
3. Get final approval of all concerned on safety, quality, quantity, cost
4. Put the new method to work. Use it until a better way is developed
5. Give proper credit where due.
Copyright © 2006 Art of Lean, Inc.
JM Review
Eliminate!
Step IIQuestion
Step IIIDevelop
Why?What?Where?When?Who?
Combine!
Rearrange!
Simplify!How
Step I. Break down the job.List all details
Step IV. Apply the new method.Sell-Approvals-Use-Credit
Copyright © 2006 Art of Lean, Inc.
Sufficientstability
MethodMaterial
MachineMan
Key points we’ll discuss…
Copyright © 2006 Art of Lean, Inc.
Why is equipment sometimes a source of instability?
Copyright © 2006 Art of Lean, Inc.
Sample Answers
•Equipment breaks down too often
•Repair time is too long
•Not enough capacity on some machines
•Change over process is too long or non-standardized
•Lots of minor stops
•Poor operator training
•Lack of spare parts
•Shortage of trained people in maintenance
All of these items happen to companies in manufacturing and need tobecome the focus of improvement efforts.
Copyright © 2006 Art of Lean, Inc.
Six machine losses
Machinelosses
Availability
Performance
Quality
Breakdowns
Changeover
Cycle time
Small stops
Scrap & rework
Categories Types
Yield or start- uplosses
Typically machines experience losses in these main categories.Each one often needs to be measured in detail
Copyright © 2006 Art of Lean, Inc.
Actual losses for an operation
GC1444Capacity
648
Break-downs
ChangeOver
CycleTime
MinorStops
Scrap Rework ActualAverageOutput
400
Net lossPer shift38.3%
61.7%
Units pershift
100
2065
3020
13
248
Illustrative Example
Losses!
Copyright © 2006 Art of Lean, Inc.
1. Breakdowns
(%)
Pareto’s Curve Graph
Problem
MachineMan
MaterialMethod
Cause and Effect Diagram
# of incidents
Type of incident
The same type of rigor that is used in “quality” problem solving should beapplied to “machine breakdown” problem solving…
Copyright © 2006 Art of Lean, Inc.
Original 5 Why’s in maintenance
Symptom: The machine stopped!
Cause: 1)The circuit overload tripped
2) The shaft was worn down and seized up
3) Metal cutting chips penetrated the area
4) Chips passed through the lubrication system
5) There was no strainer on the inlet pipe from the tank
Why?
Why?
Why?
Why?
Why?
This may not actually be the final root case but at least at this
level a countermeasure can be put in place to stop the problem
from recurring again.
Copyright © 2006 Art of Lean, Inc.
2. Set Up Reduction For Changeover
Line Name
Part Name
Process Name Machine Name Part Number
Set Up Reduction Worksheet(Work element analysis, time study, problem identification sheet)
Main Set Up Work Elements
1
2
3
4
5
6
No.Time Study
Start End Total Int. Ext.
Category
Problem Point Countermeasure
7
8
9
10
11
Copyright © 2006 Art of Lean, Inc.
3. Machine Cycle Time Study
1. Automatic doors open2. Remove part from machine (or auto eject, etc.)3. Load next part4. Clamp part / Coolant on5. Table index6. Grinding wheel on (or tool rotates, etc)7. Rapid feed advance8. Air cut9. Rough cut10. Dwell11. Finish cut12. Air cut13. Rapid feed retract14. Table return / Coolant off / Air blow15. Unclamp part16. Automatic door open – Repeat cycle
2”2”2”3”3”4”4”2”18”2”20”2”4”4”2”76”
Usually only50% of the machinecycle timeis value add…
Copyright © 2006 Art of Lean, Inc.
4. Minor Stops (Machining example)
1. Cutting chips on fixtures2. Limit or proximity switch problems3. Part jamming4. Operator adjusting “something”5. Confusion of on-line and off-line work for operator6. Etc.
Copyright © 2006 Art of Lean, Inc.
5 & 6. Scrap and Yield Losses (Machining Example)
1. What is the actual capability of the process?2. Which dimension is in trouble? By exactly how
much? Since when?3. How is the condition of the tool?4. How is the tool holder condition?5. Where is the datum? What is its condition?6. How is the part located and clamped?7. How is the part measured and gauged?8. What is the condition of the various fluids (coolant,
oil, grease, etc.)9. What is the actual machining cycle program?10. What mechanical interference might be occurring?11. What is misaligned in the machine – how much?12. What is the condition of the spindle head / bearing
unit (e.g. run out)13. How good is the incoming material?14. What else is worn that can cause variation?
Process Capability
Copyright © 2006 Art of Lean, Inc.
Sufficientstability
Method
Material
MachineMan
Key points we’ll discuss…
Copyright © 2006 Art of Lean, Inc.
Why is material sometimes a form of instability?
Copyright © 2006 Art of Lean, Inc.
Sample answers
Material
1. Availability
2. Quality
Right part
Right quantity
Right time and place
Scrap
Rework
Yield Loss
Topic
Typical Answers
Toyota basic focus points
Copyright © 2006 Art of Lean, Inc.
CustomerScheduling Dept. Order
Heijunka box
WIPWIP FG Inv.
CustomerHeijunka Box
Order
FIFO FIFO
Production
Sequence
Scheduling
Process Process Process
Process Process Process
1. Replenishment Pull
2. Sequential Pull
All pull systems have a “pacemaker” & markets(MIFA)
Supplier
Raw
Raw
Copyright © 2006 Art of Lean, Inc.
Basic inventory logic
Cycle stock
Buffer stock
Safety stock
Down time losses
Quality losses
Inventory required to
fulfill average demand
Inventory to buffer
against fluctuations in
orders
Inventory to buffer
against variability in
internal mfg. processesMarket
Inventory
Average demand
x
Lead time to replenish
Standard deviation*
x
1 (covers 67% of deviation)
2 (covers 95% of deviation)
3 (covers 99% of deviation)
+
+
+
= Market inventory level
*Assuming a normal distribution
Stocking markets based upon average demandalone often will lead to shortages…
Inventory stocking logic matters…
Qty.
Time
Copyright © 2006 Art of Lean, Inc.
Sufficientstability
Method
Material
MachineMan
Key points we’ll discuss…
Copyright © 2006 Art of Lean, Inc.
Why are methods sometimes a form of instability?
Copyright © 2006 Art of Lean, Inc.
4. Act 1. Plan
3. Check 2. Do
(Standardizeor revise)
(Definition &Analysis)
(Confirmresult)
(Trycountermeasure)
*Originally known as the Shewart cycle developed by Walter Shewart in his 1939 book entitled“Statistical Methods From The Viewpoint of Quality Improvement” and later popularized by Edward Demming
Key Point:
Constantly repeat the cycle as aproblem solving tool andmanagement routine
Toyota starting point for qualityimprovement in 1960’s
1) Basic PDCA* Cycle
Copyright © 2006 Art of Lean, Inc.
PDCA – Basic Problem Solving
What
WhyPlan
Do
Check
Action
How
1. Definition of the problem
2. Analysis of root cause
3. Set Goal / Plan solutions
4. Implement countermeasure
5. Confirm results
6. Follow Up / Standardize
Place specialemphasis here!
Copyright © 2006 Art of Lean, Inc.
2) 7 QC Tools
1. Data Collection / Check sheets
2. Cause-and-effect diagram
3. Graphs / flow charts
4. Pareto chart
5. Control chart
6. Histogram
7. Scatter diagram
The 7 classic QC tools are essential in gathering data andanalyzing problems, they also help make relevant informationvisible.
The term “7 QC tools” is named after theseven tools of the famous warrior Benkei.Benkei owned seven weapons which he usedto win all his battles. Similarly from my ownexperience you will find that you will be ableto solve 95% of the problems you face if youproperly use the 7 QC tools.
Ishikawa KaoruProfessor EmeritusUniversity of Tokyo
*Different lists contain seven or eight different tools
Copyright © 2006 Art of Lean, Inc.
Benkei’s Seven Tools
Benkei’s Tools
1. Broad Axe
2. Rake
3. Sickle
4. Wooden Mallet
5. Saw
6. Iron Rod
7. Spear
*Benkei had a sword plus seven tools!
Copyright © 2006 Art of Lean, Inc.
% ofproblems
50
100
Easy25%
Medium70%
Difficult5%
• Simple5 Why
• More structuredproblem solving
• 7 classic QC tools
• Design of experiments• Taguchi method
For maximumefficiency in problemsolving learn to use theright method at theright time.
Not all problems require the same method…
Copyright © 2006 Art of Lean, Inc.
Generic A3 Report Format Example
Background
Current Situation
Goal
Root Cause Analysis
Countermeasures
Effect Confirmation
Follow Up Actions
Plan
(Left Half) (Right Half)
Do, Check, Act
Copyright © 2006 Art of Lean, Inc.
Background
Current Situation
Goal
Analysis
Action Items
Check
Follow - up
Historical context of the situation
Define where we are – what’s theproblem or opportunity?
Establish where we want to be – targetstate.
What is causing the current situation?
What other requirements, constraintsand alternatives need to be dealt with?
What are the specific actionsproposed? Who will do what bywhen? What is the intended effect?
How do we know if the action itemsare having impact?
What else should be done?
3) Basic A3 Framework
Copyright © 2006 Art of Lean, Inc.
Background• Product: stamped-steel steering brackets (left- and right-hand drive).• 18,400 brackets/month; daily shipments in pallets of 10 trays of 20 brackets.•Customer State Street Assembly is requesting price cuts and tighteningdelivery requirements.
Current Situation•Production Lead time:23.6 days•Processing time: only 188 seconds.•Large inventories of material between each process.•Long changeover times; downtime in welding.
Countermeasures :•Create continuous flow in through Weld and Assembly•Establish Takt Time: Base the pace of work through Weld and Assembly oncustomer demand•Set new Weld-assembly cell as pacemaker for entire value stream•Establish EPEX build schedule for stamping based on actual use ofpacemaker cell and pull steel coils from supplier based on actual usage byStamping.•Reduce Changeover time in Stamping and Weld•Improve uptime in Weld•Establish material handling routes for frequent withdrawal and delivery•Establish new production instruction system with Leveling Box
Analysis•Each process operates as isolated islands, disconnected from customer.•Push system; material builds up between each process.•Each process builds according to its own operating constraints (changeover,downtime, etc.•Plans based on 90 and 30-day forecasts from customer. Weekly schedule foreach department. System is frequently overidden to make delivery.
Follow-upConfirm reviews and involvement of related departments:Production Control and Material Handling, Purchasing,Maintenance, Human Resources, Finance.
Goals: Improve profitability while meeting tougher customer demands:•Reduce lead time – 23.6 days to <5 days•Reduce inventories: Stamping – <2 days
Welding – EliminateShipping – <2 days
II I I I I
ProductionControlMRP
Weekly ScheduleDailyOrder
23.6days
Lead Time
Supplier Customer
ProductionControl
DailyOrder
4.5daysLead Time
Supplier Customer
Future State Map
Current State Map
CCF at PacemakerKaizen each c/t to <TTWeld uptime to 100%c/o reduction to <TT
Pull at PacemakerFG = 2 daysKBMt’l handlingLeveling Box
Pull from StampingWIP = 1 dayc/o < 10 min
Pull from SupplierInfo flowDaily deliveryRM = 1.5 days
1 2 3 4 5 6 7 8 9 10 11 12DELIVERABLES RESPONSIBLE REVIEW
Assy Spvr
Mt’l HndlgSpvr
Mt’l HndlgSpvr
Prod CtrlSpvr
Plt MgrVSMgr
Plt Mgr,MH MgrVSMgr
Plt MgrMH MgrVSMgrPC MgrPlt MgrVSMgr
Copyright © 2006 Art of Lean, Inc.
Sufficientstability
MethodMaterial
MachineMan
Final Review…
Copyright © 2006 Art of Lean, Inc.
TPS Summary 1973
First TPS Manual.1973 Education & TrainingDepartment
1. TPS is a series of related activities aimed atelimination of waste in order to reduce cost,improve quality, and improve productivity.
2. Scientific Mindset: On the shop floor it is importantto start with actual phenomenon and search for theroot cause in order to solve the problem. In otherwords we must emphasize getting the facts..
3. In problem solving the purpose must bemade clear…in terms of Kaizen the needs mustbe made clear.
“Practice over theory”
Managing Director
Ohno Taiichi
Copyright © 2006 Art of Lean, Inc.
Let’s review some basic TPS questions
1. How will yousatisfy thecustomer andobtain a profit?
2. What are yourmain problemsin production(or elsewhere) ?
3. How will youachieve 100% JIT?
4. How will youbuild in 100%quality?
5. How will youstabilize theoperation 100%?
6. How will youstandardized work100%?
7. How will youdevelop naturalwork team leaders?
8. How will yousustain andimprove?
•On-time delivery•Inventory•Lead-time
•Customer defects•Scrap•Rework
•Capacity losses•Downtime•Scrap & Rework
•Labor productivity•Scrap & rework•Safety
•Team morale•Skills development•Small improvements
•Recurring problems•Firefighting•Poor problem solving
Typical Problems
Countermeasuresor analysis tools
•VS Mapping•Flow of product•Pull system / kanban
•Abnormality detection•Stop the machine•Process Cpk
•6 losses•OA / Maintenance•Problem solving
•Job Instruction•Standardized work•Motion analysis
•TWI/JR•TWI/JI•TWI/JM
•PDCA•Root cause analysis•Recurrence prevention
Key TPS Questions
Copyright © 2006 Art of Lean, Inc.
TPS is built on the scientific way of thinking*…
TPS Basic Problem Solving / Kaizen1. Define the problem / opportunity2. Analyze the causes3. Set a goal4. Implement the action items5. Check the results6. Follow up / Standardize
General Scientific Method1. Define the question / make observations2. Gather information and facts3. Form hypothesis4. Perform experiment and collect data5. Analyze data6. Interpret data and draw conclusions7. Summarize results
*Quote by Taiichi Ohno. Graphic and comment byHajime Ohba Toyota Supplier Support Center
Copyright © 2006 Art of Lean, Inc.
•How might following the discussed methods helpimprove process stability?
•What areas are of the most interest to you?
Final Questions