Breaking Through to Flow

Lean Enterprise Academy 2005

Ian Glenday and Rick Sather


Breaking ThroughTo Flow


What is

LEAN?


LEAN =

• Creating flow in the value stream

• Eliminating waste (=muda)


Toyota Lean Model


Production Levelling or Heijunka

mixed sequence one piece flow matched to market pullthroughTAKT time

= PERFECT FLOW


Production Levelling or Heijunka

= Foundation of Lean

Therefore essential to beinga truly Lean Enterprise

BUT HOW TO DO IT ?


• Final step in the process, not how Toyota started

• What you see is different to how it was achieved

• Need to know the “secret” of how it was done


Supply Chain Logic IssueBuffer Tank


Supply Chain Logic Issue

Result:

• A different plan every time


Supply Chain Logic IssueConsequences:

• Increased fixed costs• Increased communication • Increased risk

High chance somethingwill go wrong resulting in:



Does your businessesever make

short term plan changes?


What impact do short term plan changes have on:

- People- Continuous improvement- Customer service- Efficiencies & costs


Supply Chain Logic IssueDifferent

plansThings

go wrong

More

wasteMore

Change-overs

Finish Good

shortages

Unplanned

changes

Loss of

capacity


Current supply chain logic:• Creates peaks & troughs

Also responsible for creating:• Different plans• Short term plan changes

Yet still the fundamental supply chain Yet still the fundamental supply chain logic used in many (most?) logic used in many (most?)

companiescompanies

Summary


• Real buffer tank

• Same logic as:– SPC– SQC

Alternative logic


• Continuously produce all products• Not see level in buffer tank

Implications?

Clearly RIDICULOUS !

Alternative logic


PARADIGM

What today seems impossible to do

but

if it could be done

would fundamentally change what you do.


PARADIGM SHIFT

A change from one of thinking to another.

It’s a revolution, a transformation,a sort of metamorphosis.

It doesn’t just happen but is driven byagents of change.


• Understanding levelled production– Steps of heijunka


Steps for implementing Heijunka

- starting point Monthly Production

• One batch per month per product

• Min. change overs• Max. batch sizes



- step 1 Twice Monthly Production

• Halve batch sizes• Identical sequence• Two cycles• Every Product

Every Cycle



- step 2 Weekly Production

• Halve batch sizes• Identical sequence• Every Product

Every Week



- step 3 Daily Production• One batch per day• Identical sequence• Every product

every day



- step 3 Daily Production• One batch per day• Identical sequence• Every product

every day

Continuous production of all products


SUSPEND YOUR SCEPTICISM !!

• That’s all very well for Toyota

• Wonderful in theory but not practical

• It would never work in our business

• Every Product Every Cycle – ridiculous when we make over a thousand SKU’s



Remainingsteps of heijunka



- step 4 Fixed Volume Production

• Daily multiple batches of same product at a fixed size

• Fixed sequence broken



- step 5 Synchronised Production• Batch sizes of one =

One piece flow• Mixed stream • Synchronised to

market pull through takt time


mixed sequence one piece flow matched tomarket pull through TAKT time

However:

Every Product Every Cycle=

Supporting structure to achieve it

Objective of Levelled Production is:

Summary


EVERY PRODUCTEVERY CYCLE

- Counter-intuitive

- In conflict with “traditional” views of efficiency


ECONOMIES

OF

REPETITION

Making the apparently impossible

POSSIBLE !


Economies of Repetition

• Repetitive Flexible Supply game

• Happens in actual implementation

• Reason why EPEC has to be EVERY

• Three separate aspects


Economies of Repetition

• Learning Curve

• Routines

• Clear objective– Stimulate skills & inventiveness – Clear goals are motivating – “Just do better” is de-motivating


Consequences & BenefitsEconomies of repetition• Higher efficiencies• Better product quality• Less waste• Greater teamwork• Clearer responsibilities• Less fixed costs

EPEC• Routine JIT deliveries• Lower stocks• Creating mtl flows easier• Reduced lead-time• Better TPM• Greater flexibility• Increase customer

service


Economies of RepetitionFasterEPEC

- Learning curve- Routines- Clear objectives

Economiesof

Repetition

NaturalContinuous

improvement

AboveExpectation

results


Economies of Repetitionfine in theory, but………

can’t do Every Product Every Cycle with current plant & equipment

therefore…….

won’t get Economies of Repetition !


Getting started with

Every Product Every Cycleand

Levelled Production

Education

Breaking Through to Flow