1. Class 24: Process Integration: Lean Operations Chapter 10.1-10.4
OPSM301 Spring 2012
Class 24:
Process Integration: Lean Operations
Chapter

2. Announcements
Class on Thursday May 10 in SOS 180

3. Paradigm of Lean Operations: In Search for the Holy Grail
The ideal Process =
Synchronization of all flows
production on demand
defect free
At lowest possible cost
Waste = Gap between ideal and actual
How do we sync at lowest cost?  Lean Tools
How do we set up a system to continually reduce waste ?
J.A. Van Mieghem/Operations/Lean Ops

4. The architect behind Lean Operations:
The architect behind Lean Operations: Toyota’s Taiichi Ohno and waste elimination
Taiichi Ohno: “Toyota Production System: Beyond Large-Scale Production”
Sources of waste at Toyota:
1. Overproduction
2. Waiting
3. Inessential handling (transportation)
4. Non-value adding processing
5. Inventory in excess of immediate needs
6. Inessential motion
7. Correction necessitated by defects
Lean operations has been defined as “a business system for organizing and managing product development, operations, suppliers, and customer relations that requires less human effort, less space, less capital, and less time to make products with fewer defects to precise customer desires, compared with the previous system of mass production.”
J.A. Van Mieghem/Operations/Lean Ops

5. Is lean dead?
The just-in-time approach to manufacturing, which has swept the world's factories over the past two decades, has made a virtue out of keeping inventories lean. But some manufacturers think it has gone too far, and that having a little extra padding might be a healthier option.
Wall Street Journal (Apr 29, 2011).

6. Some Japanese Kaizen-continuous improvement Muda-eliminate waste
Jidoka-quality at the source, root cause
Heijunka-level production, mix model
Kanban-JIT (just intime)-a mechanism to “pull” production

7. Lean Tool #1: cut batch sizes An illustrative example
Consider the following 4-step process:
What is:
The bottleneck:
The process capacity or maximal R:
The theoretical flow time Tth
The minimal amount of inventory needed to run at capacity:
Ith
Call this scenario 1, the best. Let’s now consider what happens if we have (transfer) batches A
1 min/job
Resource 1 B
Resource 2 C
Resource 3 D
Resource 4
J.A. Van Mieghem/Operations/Lean Ops

8. Lean Tool #1: cut batch size ABCD example continued
Batch Shop (Batchsize = 4)
Flow Shop (Batchsize = 1) A B C D
Elapsed Time 1 T 2 3 4 5
T = I = R =
= scenario ? A B C D 1 2 3 4 6 5 8 7 1 2
Elapsed Time 3 4 9 6 5 8 7 1 2 1 3 2 4 4 3 6 5 9 6 5 8 7 1 2 1 3 2 4 T 8 7 9
T = I = R =
J.A. Van Mieghem/Operations/Lean Ops

9. High-Inventory Manufacturing
Order :
1000 units
4 months (24 hrs a day, 7 days a week)
A : 1/2 hr/unit
inventory
B : 1/10 hr/unit
avg.
inventory
C : 1 hr/unit
B : 1/10 hr/unit
D : 3/4 hr/unit
Time (hours)

10. Low-Inventory Manufacturing
Order :
1000 units
2 months
Move batches of 200
Release materials according
to the bottleneck
A : 1/2 hr/unit
B : 1/10 hr/unit
C : 1 hr/unit
inventory
B : 1/10 hr/unit
avg.
inventory
D : 3/4 hr/unit
Time (hours)

11. When do you detect quality problems?
Quality control A B C B D
Damage done

12. How do you incorporate engineering changes?B C B D
Engineering change one month
after start of order

13. Shorter Lead time - High margins
Quoted lead time of the order is 3 months A B C B D
overtime
No overtime

14. Lean Tool #2: process on demand = pull Just-In-Time operations
JIT = have exactly what is needed, in the quantity it is needed, when it is needed, where it is needed.
J.A. Van Mieghem/Operations/Lean Ops

15. Lean Tool #2: Synchronization with demand:
Lean Tool #2: Synchronization with demand: customer demand pulls product
Supplier
inputs
outputs
Process
Customer
PUSH: Inputs availability triggers execution
Supplier
inputs
outputs
Process
Customer
PULL: Outputs need triggers execution
J.A. Van Mieghem/Operations/Lean Ops

16. Lean Tool #2: Pull Implementation: Kanban Production Control Systems
Processing center i
Processing center i + 1
WIP
Job
J.A. Van Mieghem/Operations/Lean Ops

17. Lean Tool #3: Quality at the Source
Stage: At Source Next Process End of Line Final Inspection End User
Cost:
Impact: • Little • Minor • Rework • Much rework • Warranty
delay • Reschedule • Delivery delay • Complaints
• Inspect more • Reputation
• Market share

18. Reducing Waste: Quality at the Source
Fool-proof/Fail-safe design (Poka-Yoke)
Inspection
Self
Automated (Jidoka)
Line-stopping empowerment (Andon)
Line-stopping empowerment
Poka Yoke and Jidoka
Trouble!
Approach for operators
• Preventative
• If trouble, STOP!
• If defective don't pass
Approach for machines
A mistake-proofing system prevents errors and defects
Stop line when defects are detected or machine breaks down
J.A. Van Mieghem/Operations/Lean Ops

19. Lean Tool #4: Flexible Resources & Standardized Work
Cross training of workforce allows resource pooling
Use of IT in services
Standardisation helps a system be highly flexible to respond to variability – ball boys and girls have very standardised processes but the ball can go anywhere …
Copyright © 2013 Pearson Education Inc. publishing as Prentice Hall
J.A. Van Mieghem/

20. Lean Tool #5: Heijunka Mixed Level/Balanced Production
Batch Production Schedule Mixed Production Schedule
(AAAABBBB..) (ABAB...)
Product April April A B
FGI
FGI
Stress:
this is only for multi-product settings
Role of setup/changeover time reduction
Role of frozen schedules
Role of mixed pickups/logistics
time
time
J.A. Van Mieghem/Operations/Lean Ops

21. Lean Tool #6: From Functional Layout to Product Cell organization
Production
Control
Roof
Cut
Base FA
Assy
Department 1
Production
Control
Production
Control
Production
Control
Cell 1
Department 2
Department 2
Roof
Cut
Roof
Cut
Roof
Cut
Base
Cut
Base
Cut
Base
Cut
Production
Control
Roof
Cut
Base FA
Assy
Production
Control
Roof
Cut
Base FA
Assy
Department 2
Department 2 FA FA FA
Base
Assy
Base
Assy
Base
Assy
Cell 2
Cell 3
J.A. Van Mieghem/Operations/Lean Ops

22. Towards a system of continuous improvement: Increase Problem Visibility– River Analogy
Scrap &
Rework
Missed Due Dates
Too Much Space
Late Deliveries
Poor Quality
Machine Downtime
Engineering Change Orders
Long queues
Too much paperwork
100% inspection
Inventory
Copyright © 2013 Pearson Education Inc. publishing as Prentice Hall
J.A. Van Mieghem/Operations/Lean Ops

23. Copyright © 2013 Pearson Education Inc. publishing as Prentice Hall

24. Visibility: Time plays the role of Inventory in Lean Service Operations
Instead of I, look at promising 2 weeks to customers
But
Track internally whenever T > 13 days,
+ Investigate + Reduce sigma.
J.A. Van Mieghem/Operations/Lean Ops

25. Towards a system of continuous improvement: Kaizen Tools
Reduce variability
Standard operating procedures
Increase visibility of waste and quality at source
Line-stopping empowerment (Andon)
Quality inspection: Self & Automated (Jidoka)
Fool-proof/Fail-safe design (Poka-Yoke)
Targeted improvements: root cause analysis (5 Why’s)
Active worker involvement
Time for experimentation
Supplier involvement
Exploratory stress
Human infrastructure & process measurement and review (visual management)
J.A. Van Mieghem/Operations/Lean Ops

26. Learning Objectives Lean Operations
Paradigm of Lean Operations:
Strive for the ideal by eliminating waste
This is a total business management system
Synchronization Tools
Reduced batch sizes
Pull production control systems (vs. push)—JIT & Kanban control
Quality at the source
Resource pooling
Level loading (Heijunka)
Layout: Cellular operations
Set up a System for Continuous Improvement
Reduce variability (standard operating procedures)
Increase visibility (river analogy)
Improve human infrastructure
J.A. Van Mieghem/Operations/Lean Ops

27. How about the workers?
Modern Times by Charlie Chaplin

28. Worker s’ Response to TQM Implementations in Turkey
A study in Brisa Factory,1998:
Positive Results of TQM:
44% reduction in accidents, 50% reduction in absenteeism and turnover rate
Worker education levels increased
Job security increased- this is regarded as the most important issue by the workers
There were also complaints:
More intense work, need to work more

29. Quotes from Workers:
Reference: Engin Yıldırım: “Modern Management Techniques in the Developing World: The Case of TQM and its Impact on Workers in Turkey”
Work, Employment, Society, 1999, vol. 13, no. 4, pp

30. Not only controlling actions bu also ideology
A critisism of Lean Management System: From despotic management to hegemonic management*
Not only controlling actions bu also ideology
control by creating a commonality of interests where conflict is replaced by mutual interest and co-operation.
Toyotasa attempts to establish hegemony in the factory, which would not leave the worker’s brain in a state of freedom, allowing for the possibility of non-conformist thoughts
Reference: Gamze Yücesan-Özdemir: “Hidden Forms of Resistance among Turkish Workers: Hegemonic Incorporation or Building Blocks for
Working Class Struggle?” Capital and Class, no. 81, Autumn 2003, pp

31. Some quotes from workers on how they feel about working environment:
Reference: Gamze Yücesan-Özdemir: “Hidden Forms of Resistance among Turkish Workers: Hegemonic Incorporation or Building Blocks for
Working Class Struggle?” Capital and Class, no. 81, Autumn 2003, pp

32. Improvement as a process
OPNS454 Week 9: Improvement and Innovation
4/18/2018
The Ideal Operation
perfectly synchronized with demand
at lowest cost
D = deviation from ideal
= waste, variability, inflexibility
= opportunity for improvement
The Actual Operation
Continuous
Improvement
Process
Increase visibility of D
Andon pulls, workplace organization
Exploratory stress
Process measurement, visual management
Remind them of lean ops philosophy discussed in the core class + role of visibility (later, automation may reduce this) and employee involvement in kaizen (standardization will reduce this)
Reduce D
Root cause analysis & problem solving mindset
Waste reduction (Lean tools)
Variability reduction (Six Sigma, TQM)
OPNS454 © Van Mieghem

33. Ongoing objectives Improve process flows Increase process flexibility
Efficient plant layout
Fast and accurate flow of material and information
Increase process flexibility
Reduce changeover times
Cross-training
Decrease process variability
Flow rates
Processing times
Quality
Minimize processing costs
Eliminate transportation, inspection, rework

34. How? Improve process flows Increase process flexibility
Cellular layouts
Demand pull mechanisms
Increase process flexibility
Fast changeovers
Smaller lotsizes, level production
Decrease process variability
Standardize
Improve supplier reliability and capacity
Safety capacity, preventive maintenance
Fast feedback and correction
Minimize processing costs
Improve quality, eliminate non-value-adding activities