Lean production, a term used interchangeably with Lean manufacturing, aims to eliminate waste, maximize efficiency, and improve quality by adopting a mindset of continuous improvement. The methodology of Lean production was first developed by the Toyota Motor Corporation in the 1950s and 1960s who titled their revolutionary manufacturing principles the Toyota Production System.
Taiichi Ohno, considered the father of the Toyota Production System, established seven common types of wastes in mass manufacturing, processes and resources that do not add any value for the customer:
- Non-utilized talent
- Excessive processing
Today, many Lean professionals include an eighth waste: non-utilized talent, or skilled employees whose experience is not adequately utilized by management.
TPS was built upon two foundational philosophies to address these wastes as well as the waste of mura (uneven or irregular production levels) and muri (overworked employees or machines):
- Just-in-Time systems are a type of production control system operating under the philosophy of producing only what is needed (actual customer demand), when it is needed, and in the amount needed instead of trying to predict customer demand.
- Jidoka means automation with a human touch and is one of the earliest concepts developed, first being used in 1924 with the Toyoda Automatic Weaving Loom. Also known as autonomation, Jidoka is the concept that equipment should stop immediately when a problem arises as to prevent the production of defective products.
Toyota found great success with this new way of manufacturing becoming one of the top leaders in the automobile industry. The combination of Toyota sharing TPS with other organizations in the 1990s and the 1990 publication The Machine That Changed the World introduced the rest of the world to these groundbreaking concepts, effectively setting the stage for Lean production.
Lean productions systems use many of the tools and strategies developed by the Toyota Motor Corporation:
- Kaizen is a continuous improvement mindset. It is the belief that processes can always be improved and making continuous small improvements will have a major impact over time.
- Heijunka is a Japanese term meaning production or production smoothing. Essential for Just-in-Time production and an effective Kanban system, heijunka eliminates waste by manufacturing batches as small as possible and leveling production either by olume or product.
- Kanban is the operating component of a just-in-time production system. Kanban cards and bins are sent down the line to streamline processes and keep batch sizes small and production only happens when the visual cue is sent to trigger an action.
- 5S is sometimes thought of as a housekeeping strategy for facilities, factories, and warehouses. Although at its core 5S is based on organization, it is a strategy that works to meet the Lean goals of eliminating waste and
- Gemba walks and genchi genbutsu are two principles that fall under the same philosophy, the concept that the most effective way management and leaders can understand issues, or their production line is by going and observing the process up close.