Lean Manufacturing

1
Lean Manufacturing Just-in-Time

• "The most dangerous kind of waste is the waste we
  do not recognize." - Shigeo Shingo

2
Reducing Waste Push versus Pull System
3
Push System

• Every worker maximizes own output, making as many
  products as possible
• Pros and cons
• Focuses on keeping individual operators and
  workstations busy rather than efficient use of
  materials
• Volumes of defective work may be produced
• Throughput time will increase as work-in-process
  increases (Littles Law)
• Line bottlenecks and inventories of unfinished
  products will occur
• Hard to respond to special orders and order
  changes due to long throughput time

4
Pull System

• Production line is controlled by the last
  operation, Kanban cards control WIP
• Pros and cons
• Controls maximum WIP and eliminates WIP
  accumulating at bottlenecks
• Keeps materials busy, not operators. Operators
  work only when there is a signal to produce.
• If a problem arises, there is no slack in the
  system
• Throughput time and WIP are decreased, faster
  reaction to defects and less opportunity to
  create defects

5
Features of Lean Production
6
A Little History!

• Ford Design for manufacturing
• Start with an article that suits and then study
  to find some way of eliminating the entirely
  useless parts. This applies to everything a
  shoe, a dress, a house, a piece of machinery, a
  railroad, a steamship, an airplane. As we cut out
  useless parts and simplify necessary ones, we
  also cut down the cost of making. ...But also it
  is to be remembered that all the parts are
  designed so that they can be most easily made."

7
A Little History!

• Ohno put ideas into practice systematically
• When bombarded with questions from our group on
  what inspired his thinking, Ohno just laughed and
  said he learned it all from Henry Ford's book."

8
TPS Toyota Production System

• A system that continually searches for and
  eliminates waste throughout the value chain.
• Views every enterprise activity as an operation
  and applies its waste reduction concepts to each
  activity - from Customers to the Board of
  Directors to Support Staff to Production Plants
  to Suppliers.

9
Elimination of Waste
Muda
Acronym CLOSED MITT

• Complexity
• Labor
• Overproduction
• Space
• Energy
• Defects

• Materials
• Inventory
• Time
• Transportation

10
Elimination of Waste

1. 5S
2. Group technology
3. Quality at the source
4. JIT production
5. Kanban production control system
6. Minimized setup times
7. Uniform plant loading
8. Focused factory networks

11
Minimizing Waste 5S
Good factories develop beginning with the 5Ss.
Bad factories fall apart beginning with the 5
Ss. - Hirouki Hirano
Japanese Translation English
Seiri Proper arrangement Sort
Seiton Orderliness Simplify
Seiso Cleanliness Sweep
Seiketsu Cleanup Standardize
Shitsuke Discipline Sustain
12
Minimizing Waste 5S

• A place for everything and everything in its
  place
• Not just a housekeeping issue
• Critical foundation for
• Setup reduction
• Pull systems
• Maintenance
• Inventory management

13
Minimizing Waste Group Technology

• Using Departmental Specialization (Job Shop) for
  plant layout can cause a lot of unnecessary
  material movement

Note how the flow lines are going back and forth
Saw
Saw
Grinder
Saw
Grinder
Heat Treat
Lathe
Press
Press
Lathe
Lathe
Press
14
Minimizing Waste Group Technology

• Revising by using Group Technology Cells can
  reduce movement and improve product flow

Grinder
2
1
Press
Lathe
Lathe
Saw
Heat Treat
Grinder
Press
A
B
Lathe
Lathe
Saw
15
Minimizing Waste JIT

• Only produce whats needed
• The opposite of Just In Case philosophy
• Ideal lot size is one
• Minimize transit time
• Frequent small deliveries

???

• Pros
• Minimal inventory
• Less space
• More visual
• Easier to spot quality issues

• Cons
• Requires discipline
• Requires good problem solving
• Suppliers or warehouses must be close
• Requires high quality

16
Inventory Hides Problems
Minimizing Waste JIT
17
Minimizing Waste Quality at the Source

• Do it right the first time
• Call for help
• Immediately stop the process and correct it vs.
  passing it on to inspection or repair

Andon
18
Jidoka
19
Minimizing Waste Kanban

• Signaling device to control flow of material
• Cards
• Empty containers
• Lights
• Colored golf balls
• Etc

20
Minimizing Waste Setup Times

• Long setup times drive
• Long production runs
• Large lots
• Long lead times
• JIT requires small lots and minimum kanbans
• Setup reduction
• Focused efforts
• Problem solving
• Flexible equipment

21
Minimizing Waste Plant Loading
Heijunka
Suppose we operate a production plant that
produces a single product. The schedule of
production for this product could be accomplished
using either of the two plant loading schedules
below.
Not uniform Jan. Units Feb. Units Mar.
Units Total 1,200 3,500 4,300 9,000
or
Uniform Jan. Units Feb. Units Mar.
Units Total 3,000 3,000 3,000 9,000
How does the uniform loading help save labor
costs?
22
Minimizing Waste Focused Factory Networks
These are small specialized plants that limit the
range of products produced (sometimes only one
type of product for an entire facility)
Coordination
System Integration
23
TPS Respect for People

• Level payrolls
• Cooperative employee unions
• Subcontractor networks
• Bottom-up management style
• Quality circles (Small Group Problem Solving)

Keiretsu
24
TPS 4 Rules

1. All work shall be highly specified as to content,
   sequence, timing, and outcome
2. Every customer-supplier connection must be
   direct, and there must be an unambiguous
   yes-or-no way to send requests and receive
   responses
3. The pathway for every product and service must be
   simple and direct
4. Any improvement must be made in accordance with
   the scientific method, under the guidance of a
   teacher, at the lowest possible level in the
   organization

25
Lean Implementation
Total Quality Management
Product Design
Flow Process
Empowered Workforce Problem Solving Performance
Measurement
Stable Schedule
Continual Inventory Reduction
Kanban Pull
Involved Suppliers
26
Summary and Conclusions

• Lean Production is the set of activities that
  achieves quality production at minimum cost and
  inventory
• The flow of material is pulled through the
  process by downstream operations
• Lean originated with the Toyota Production System
  and its two philosophies elimination of waste,
  and respect for people
• CLOSED MITT forms of waste