LEAN production #2: the Three M’s to improve your business
Identify the source of your unproductiveness
In my previous article about Lean, I made a brief introduction of the method and wrote about the different types of wastes that one can reduce to improve productivity.
Moreover, the Lean core can be summarized on a broader set of points [1]:
- Create a continuous flow of products.
- Increase the flexibility of the business to meet the customer demand.
- Make use of quality and quantity control to eliminate waste.
- Establish a pull production through the whole process.
- Maintain a continuous improvement, creating a Lean culture and involvement from everyone. Continuous monitoring and reporting.
“Lean is not a state, it is a process”
In order to reach these objectives, the Lean system introduces three Japanese concepts that help us to understand the origin of the problems in the production: MURA, MURI and MUDA. I will briefly explain these concepts and list some tools to work on them.
MURA
This property of our work processes refers to the inconsistency in the use of resources. From its Japanese origin, it comes from the idea of unevenness or irregularity. In certain contexts, it is a synonym of the word ōtotsu (凹凸), that is formed by the symbols or concave and convex, one next to the other.
It can be produced by several internal or external factors, as for example uneven customer demand, irregular scheduling of work, inappropriate distribution of the workload, or irregular quality of the work equipment.
There are many tools that will help to balance properly the production:
- Process/ Value Stream Mapping
- 5S (Sort, Shine, Set in order, Standardize, Sustain)
- Visual Management
- Takt Time
- Heijunka (Production Levelling)
MURI
Muri or overburden can refer to labor or to the use of machines, tools or procedures.
The word is formed by the symbols of lack (無) and reason (理), creating the concept of something irrational, excessive, incapable.
For example, our process has Muri when people are working too much to keep up with the demand. There is also Muri when people have to work too fast, when the machines are overloaded to get more results, or when the quality processes or the maintenance are skipped to reduce production times.
Some useful tools to focus on the elimination of Muri are the followings:
- 5S (Sort, Shine, Set in order, Standardize, Sustain)
- Takt Time
- Heijunka (Production Levelling)
- Setup Time Reduction
MUDA
Muda is probably the best known of these three properties. Actually, when we talk of Muda we are referring to the waste elimination, that we already covered in my previous article about Lean.
The etymology is quite special since it is a combination of the symbols for lack (無) and horse-load (駄). Both combined create the concept of waste and uselessness as if you were wasting your efforts by carrying your own pack when you could be using your horse. I can be understood as a “lack of efficiency”.
Some additional tools to work over this problem are:
- Setup Time Reduction
- Just-in-Time
- Poka Yoke (Error Proofing)
- Jidoka (Stop & Fix)
Conclusions
Mura, Muri, and Muda are three basic ideas that we must know to identify the source of our inefficiency. We can make use of any of the many known tools to eliminate the source of our production problems, separated into these three parts.
For this, we just need to analyze our processes and our work environment and check if our production system is stable and properly optimized.
All the Three M’s are closely related. The existence of Mura induces periods of time with excessive workload (Muri), and there will be also periods of low activity in which the resources will be wasted (Muda).
Innovation is always spinning forward. Just like a Drill.
References
[1] Grunow, M. and Ott, H. (2018). Lean Production. [online] edX. Available at: https://www.edx.org/course/lean-production-tumx-qpls3x-0 [Accessed 7 Jul. 2018].
