LEAN MANUFACTURING: KAIZEN, HOSHIN and TPM The differences and advantages of these improvement processes

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- Objectives of either continued or emergency improvement processes,
- Differences between them.

The common factors

Productivity gains with these methods:
- Increased customer confidence
- Less social problems
- Reduction in costs associated with poor quality
- Less accidents in the workplace
- Involves everyone
- Avoids investment in new machinery

The objectives?

To be kept visible:
- Zero stock
- Quality
- Continued improvement

Hidden, complementary:
- Effective from the outset,
- Work standards,
- Work in a pull system.

Points of note:

"0 stock" without "pull flow":
- 56% of factories are dissatisfied with their stock levels
- 14% work in JIT with their suppliers,
- the majority work according to their stock and sales forecasts and not on the flow line
- Lack of confidence in the methods: many run trials without taking them far enough

Good outset:
- 82% of factories put a cooperative work tool in place
- 90% set up a reporting system
- 41% do not have an immediate alert system
- They tighten their quality levels, but they do not concentrate on reactivity, or finding the root cause, or the implication of the management,
- Most do not put basic LEAN principals in place.

Carrying out these steps does not depend on the size of the business, but on the sector.

The fundamental principals of Lean Manufacturing:

- happen in "Gemba" or "Genchi-Gembutsu" with the products
- try to improve product quality
- allow a standard to be defined

KAIZEN: continued improvement.

In Japanese, the word "KAIZEN" means: small improvements involving everyone from director to worker above all, using common sense.

The process is based on:

- small improvements made day by day
- but constantly
- at low cost
- involving everyone
- using common sense
- with a non-elitist character, available to everyone, all the time

It is a gradual and gentle step that goes against the more Western concept of brutal reform where "we throw everything out and start again from scratch"

2 principals to respect: "Gemba" and elimination of "Muda"

Gemba means a real place where added value is produced
in other words, where the action takes place, where the added value is created and where the customer finds satisfaction. In production, Gemba is often synonymous with the "work station", or the shop floor.
Therefore, we work with the teams at their work stations.

Muda means waste, but on a large scale:
- Any operation not generating added value,
- Having to look for a tool that is not immediately available,
- Overproduction and stock
- Accumulation of things that are not immediately necessary
- Defective products needing repair or destruction,
- Usless movements,
- Procedures demanding inefficient or useless tasks
- Non synchronisation of systems
- Inactivity during line changes, tool changes or equipment breakdown,
- Logistics: inadequate timing, excessive movement or bad deliveries

Principal of making problems visible: "visual management"

Traditional approach Kaizen approach
Hiding tasks Making tasks visible

the principal also very applicable to stock with visual minimum levels: Kanban : outil de visual management en Lean.

LEAN is a system:
- made up of known tools: SMED, FMEA, 5S, etc...
- linking these tools with one another
- a philosophy of perfection,
- but also a management methodology.
- works with:

  • Six Sigma,
  • ISO 9000,
  • ISO TS.

- differences from Six-Sigma :

  • just one special team: Green / Black Belts bring the projects to the factory and demonstrate the methods of solving them
  • in Lean, the projects come from the basics: it is a change in management.

Measuring the progress:
Each LEAN task has to have a measurable effect on one or several physical indicators. For example:

- 30% on the rejects and quality
- time saving of up to 50% during a line change
- in 3 to 12 months.

What Lean Management does not do:
- Restoring,
- Fire fighting.

To complement this step in the long term, there is:

LEAN HOSHIN or KAIKAKU campaign, or Kaizen Blitz: rapid action breakthrough
In order to initiate the LEAN and to prolong it by Kaizen, it is important to give an unsimulated kickstart and to give an example that is as quick as it is visible.

As with Kaizen, it brings together:
- participative character / group work
- a measure of the stakes for the business and its employees

The characteristcs of a Hoshin project:
- campaign on an unrestricted shopfloor,
- short term: one week,
- place of added value important, where the current results are weak but the potential gains are big.

The key success factors of Kaikaku / Hoshin methods:
- a clear limit of the task
- a collection of data helping to know the direction to take: helping in rapid analysis
- a tool capable of managing tension in the team to lead it to the objective

as errors are not allowed: its success sets the example to continue with the Kaizen task.

Be careful not to make the mistake of continuing to apply this kind of action throughout as it will inhibit the participation of the operators who are working to the Kaizen process of continued improvement.

Differences between the steps: prerequisits of selection

Start upLean KaizenLean HoshinTPM
Global domain Factory Shopfloor Machines
Has global workshop indicators No No
OEE Unstable Stable Unstable
Autonomous teams Few Few Yes
Number of production stages >3 1 to 2 1
Machine park Good Good Re-check
Innovation need No No Yes
Duration 1 year 1 week to 1 month 6 months to 1 year
Targets Workforce + Machines Workforce + Machines Machines, process, maintenance
Objectives Stabilise, progress continually Increase rapidly Increase rapidly and stabilise

Common tools versus procedures

ProcedureLean KaizenLean HoshinTPM
Proactive indicators at the workstation and for management O O O
Management indicators and 5 min summary O O O
SMED (Setup reduction) O O O
5S O N
Preventative and predictive Maintenance O O O
Experimental plansPlans d’expérience O N O
Kanban, pull flow O N N
Red bins - Stop 1st flaw O O N
VSM : Value Stream Mapping & Management, Mapping of Flow Values O O N
Takt Time / Work balancing O O N
Batch size reduction / One-Piece-Flow O O N
Poka Yoke - Jidoka- Automation - Source quality O O N
Line reorganisation, Work in cells O O N
Work standards O O N

Therefore, in summary, step by step, to implement Lean:
- link the Quality control manager with the Lean manager,
- be in a growing position in order to absorb surplus staff
- identify a part of the shopfloor in a well defined area that will serve as a model and use Lean Hoshin,
- use Lean Kaizen training on the shop floor
- persuade suppliers and customers to follow your example : propose them to play with you at the Lean play.