ch-1-Intro-to-Lean mfg

8/12/2019 ch-1-Intro-to-Lean mfg.

1/26

Introduction to LeanManufacturing


2/26

Intro-To-Lean

Lean Manufacturing Definition

Lean has been defined in many different ways.

A systematic approach to identifying and eliminatingwaste(non-value-added activities) through continuousimprovementby flowing the product at the pullof thecustomer in pursuit of perfection.

By The MEP Lean Network


3/26

Intro-To-Lean

History Timeline for Lean Manufacturing


4/26

Intro-To-Lean

Lean manufacturing is a

philosophyIn 1990 James Womack, Daniel T. Jones, and

Daniel Rooswrote a book called The Machine

That Changed the World: The Story of LeanProduction-- Toyota's Secret Weapon in the Global CarWars That Is Now Revolutionizing World Industry

In this book, Womack introduced the ToyotaProduction System to American.

What was new was a phrase"Lean Manufacturing."


5/26

How to Increase Profit?

Intro-To-Lean

Profit

Cost

ProfitCost

ProfitCost


6/26

Intro-To-Lean

Muda (Waste)

Taiichi Ohno (1912-1990), the Toyota executive who was the mostferocious foe of waste human history has produced, identified thefirst seven types of mudain manufacturing system:

Storage Transportation Waiting Motion

Process Defects Over-production

Mud

ais everywhere.


7/26

Intro-To-Lean

Lean Overview


8/26

Intro-To-Lean

Lean Manufacturing Tools 5S Value Stream Mapping

Standardized Work

Load Leveling

Kaizen Kanban

Visual Workplace

Quick Changeover

Andon Poka-yoke

One-piece flow

Cellular Manufacturing


9/26

Intro-To-Lean

Production Planning System (Push System)


10/26

Intro-To-Lean

Push or Pull?

A push system


11/26

Intro-To-Lean

Push or Pull?

A pull system


12/26

Intro-To-Lean

Kanban Operation

WK(2)PK(1) PK(i+1)PK(2) PK(N)WK(1) WK(N)WK(i+1)WK(i) PK(i)

RM FG

Kanban Stage

1

Kanban Stage

i

Station

1

Station

2

Station

i

Station

i+1

Station

N+1

Figure 3.3. A kanban stage formed by two adjacent stations.

From stage i-1 To stage i+1

12

i

3

Kanban Stage

i

i +1

WKPK

4

KK-1

5


13/26

Intro-To-Lean

Finishedgoods

Raw materials inventory

Semi-finishedparts

PKPK PK WKWKWK

Station 1 Station 2

Station 3

Semi-finished parts

Material

handler Order

receiving

RMRMRM

14

3

2

1

3

4

4

5

6

7

7

7

7

8

8

9

12

13

13

11

10

11

11

11


14/26

Intro-To-Lean

Current State Map of A Case Study Example


15/26

Intro-To-Lean

Future State MapAt which stations, are parts withdrawn?At which stations, are parts scheduled?


16/26

Intro-To-Lean

Which to ChooseMRP

(ERP), or Kanban?Where MRP (ERP) works best:

MRP is by its very nature a forward-lookingsystem.

MRP can be very effective in an environment witha great deal of variability.

MRP is recognized an engine to drive an integrated

enterprise-wide information system. Purchasingand logistics activities were similarly beingintegrated with fundamental internal materialsmanagement principles into an enterprise-wideapproach.


17/26

Intro-To-Lean

MRP or Lean Manufacturing?

MRP is a predictive system. It does not reflect tocustomers demand (easy to get overproduction).

A company takes MRP suggestions and acts on them withouttoo much review is very risky.

MRP wont fully support the cost-cutting.

MRP needs lots of data for production management.

MRP generates high overhead.

MRP builds high work-in-process. MRPs lead times are fixed.

MRP creates potential quality hazard.

Where MRP is not as effective.


18/26

Intro-To-Lean

Which to Choose MRP

(ERP), or Kanban?Where Kanban works best.Kanban is a very reactive system. Very little is planned

ahead. Instead, Kanban causes replacement of material used in a

totally reactive mode. Kanban works best in a highly stable andpredictable environment.

Where it is not as effective.

Kanban can quickly fail in a highly volatile environmentbecause of the reactive nature of the system. Volatility incustomer demand, processing problems, and extensive changesin product designs make it very difficult for a Kanban system towork effectively.


19/26

Intro-To-Lean

Which to Choose MRP(ERP), or Kanban?

Kanban and MRP Combination

The combination of these two systems is becoming quite

common. An MRP system is used for advanced planning,including long lead-time purchased materials, adding resources,and implementing product design changes. Once the MRP has thematerials and resources linedup,however, Kanban is used asan execution system, bringing with the characteristics of rapid

response to customer order and reduced inventory levelsthroughout the process.

Hybrid Systems


20/26

Intro-To-Lean

The Objections to Lean

How should you deal with these objections to lean?

It is very hard to deal with raw material suppliersif we fully depend on customer order.

It takes too much discipline.It takes too long to implement.

My process is too complex; I have to deal withtoo many uncontrollable variables, like late suppliershipments, sick people, etc.

My process requires a large batch size.

It doesnt make sense in my industry.

Its unclear to me how lean will work with my

MRP system.


21/26

Intro-To-Lean

Lean and Green

The environmental impacts due to

production and waste generation

have made its way into every day

society.

Consumers are becoming more

environmentally conscious.

With the Earths limited resources,

companies are more conscious of

their carbon footprint, and there has

been a movement to create moreenvironmentally friendly decisions.

Green engineering is the systems-level approach to product and

process design where environmental attributes are treated as primary

objectives or opportunities rather than simple constraints.


22/26

Intro-To-Lean

lean manufacturing is a link

to green engineeringLean manufacturing is the business model and collection of tactical

methods that emphasize eliminating non-value- added activities

(waste) while delivering quality products at lowest cost with greater

efficiency. In conjunction, six goals of green engineering are:

1. Select low environmental impact materials.

2. Avoid toxic or hazardous materials.

3. Choose cleaner production processes.

4. Maximize energy and water efficiencies.

5. Design for waste minimization.

6. Design for recyclability and reuse of material.


23/26

Intro-To-Lean

lean manufacturing is a link

to green engineeringPopulation growsWastes increase

Fossil fuels are diminishing and there is nothing replenishing them.

Consumers are becoming more aware of the environment and

prefer environmentally friendly companies.Being lean and green is so important now to reduce the

consumption of natural resources and the CO2 concentration

in the Earths atmosphere.

The only real difference between lean and green manufacturing is

that green actually designs the product or process with the

environment as a constraint while lean creates a process with the

view of the environment as a valuable resource and not a

constraint.

Key Steps in Transforming


24/26

Intro-To-Lean

Key Steps in Transforminga Company to the Lean

Approach1. Establish a steering teamconduct strategic planning session2. Train the steering team and the model line team in the

disciplines of lean

3.Perform PQR (product-quantity-routing) analysis

4. Identify value streamsselect a value stream5. Calculate model line takt time6. Value stream map the model lineassemble current state map7. Balance the lineassign standard work

8. Establish standard WIP (inventory levels)9. Test the system (virtual cell)document results10. Setup reduction event

Key Steps in Transforming


25/26

Intro-To-Lean

Key Steps in Transforminga Company to the Lean

Approach11. Conduct 5S eventapply TPM techniques12. Establish visual signalsreduce paperwork13. Explore alternative flow patterns

14. Develop block layout15. Develop detailed layout16. Execute move17. Select next value stream and repeat

Gary Conner, President of Lean Enterprise Training, Newport, OR, Road Map to

Lean for the Smaller Shop, Society of Manufacturing Engineers, LeanManufacturing 2007, Supplement to Manufacturing Engineering, 2007. pp. 27-29.


26/26

References

Society of Manufacturing Engineers, Lean Manufacturing 2007,Supplement to Manufacturing Engineering, 2007.

Society of Manufacturing Engineers, Lean Manufacturing 2008,Supplement to Manufacturing Engineering, 2008.

Garrett Brown and Dara ORourke, LeanManufacturingComestoChina: A Case Study of its Impact on Workplace Health and Safety,

International Journal of Occupational and Environmental Health (IJOEH),

13(3), JUL/SEP 2007.

Challenges in Applying Lean Manufacturing in China, McKinseyQuarterly, 2006 Special Edition available at Jackson Library. Friday,

October 12, 2007 | Posted by Simone Yuin International

Intro-To-Lean
https://www.stanford.edu/group/jacksonlibrary/cgi-bin/jacksonblog/author/simoneyu/https://www.stanford.edu/group/jacksonlibrary/cgi-bin/jacksonblog/category/international/https://www.stanford.edu/group/jacksonlibrary/cgi-bin/jacksonblog/category/international/https://www.stanford.edu/group/jacksonlibrary/cgi-bin/jacksonblog/author/simoneyu/

Documents

ch-1-Intro-to-Lean mfg