Gemba is a Japanese Term, and literally means gathering of the people/actual place. In lean terms it is the place you add value in your workplace. For manufacturing, the Gemba is the factory. It is used to describe a meeting or event where all of the necessary people are involved simultaneously to resolve a problem or issue. The five golden rules of Gemba management are:
- When a problem (abnormality) arises, go to Gemba first
- Check the gembutsu (relevant objects)
- Take temporary countermeasures on the spot
- Find the root cause
- Standardize to prevent recurrence
The idea is to focus improvement activity at the place where people do the work that adds value to the customer, based on actual observed facts.
The major thrust of this approach is its emphasis on common sense. Successfully implemented on the floor, participants will be able to identify and eliminate the major equipment losses at their facility and improve Overall Equipment Effectiveness (OEE), which is a measure that shows the proportion of time a piece of equipment manufactures good, quality product against its potential capacity.
OEE = %Availability x %Performance x %Quality (x %Yield)
All data should be collated for the same period of time. Within these parameters are further calculations based on different factors:
Availability = Operating Time/Planned Production Time
Performance = (Ideal Cycle Time x Pieces Produced)/Operating Time
Quality = Good Pieces/Pieces Produced (breakdowns, setup, toolchange, yield, minor stoppages, cycle time inefficiency and defects/rework)