The Lean House

There are three problems inherent in any production system:

• Waste (Muda),
• Instability,
• Variability (Mura).

These problems reduce system efficiency by exerting a negative effect on quality, costs and delivery times. The end result is a lower return on investment.

The Lean-Manufacturing house

The Lean house is the symbol used by its founders to explain the coherence and harmony of the Lean system (Lean Manufacturing).

Stability is the foundation of the Lean house. Applied to an organisation, we refer to team stability, method standardisation, strategy monitored over time, etc.

The base of the house, on which all the rest is built, has 2 elements: Kaizen attitude - or continual progress - and elimination of Mudas: both set the system in motion.

The 2 pillars of the Lean house (JIT and JIDOKA) are based on:

Heijunka: smoothing and sequencing of production.

Standard work: reduced variability of the pace and processes of work: A system designed to absorb sudden demand fluctuations as well as possible.

The tools used in the walls of the house to support its roof - the objective of the method - are:

• For the JIT pillar: Pulled flow, Takt time and continuous flow.
• For the Jidoka pillar: man-machine separation (one operator manages several machines) or autonomation (one operator manages several machines).

The roof, or objective of the Lean Manufacturing method, is summarised by CQD, reduced production costs, improved quality level, matching delivery times to customer needs.