3M is a Japanese concept derived to identify and eliminate non-value-added activities present in the manufacturing process. 7 types of waste in Lean manufacturing are comes under Muda.
3M Waste are Muda, Mura and Muri.
It is called 3M since the first letter starts with “M”.
These are the three major waste that is firstly identified by Toyota Production system-TPS
3M Waste are:
- MUDA means Waste
- MURA means Inconsistency/Unevenness/Imbalance
- MURI means Strain/Overburden/Fatigue
MUDA means Waste
MUDA stands for eliminating waste or non-value-added activities from the manufacturing process. It can be anything that does not add value from the customer’s point of view.
There are 7 types of MUDA or 7 types of Waste identified in the lean manufacturing process which is as follow:
- MUDA of Overproduction
- MUDA of Process Itself/Over Processing
- MUDA of Inventory/Stocks
- MUDA of Transport
- MUDA of Waiting
- MUDA of Motion
- MUDA of Defects
>Click the link to explore the “7 types of waste.” How to reduce waste in Lean Manufacturing?
MURA means Inconsistency/Unevenness/Imbalance
Two things or activities that have large variation result in losses thereby increase the cost of operation. The Losses can be reduced by balancing or reducing Variation.
e.g. Allocation of unequal work to operators.
Countermeasure: Share workload to operators, Line balancing, Match skill of persons.
MURI means Strain/Overburden/Fatigue
MURI stands for any activity that exceeds the capacity of 4M (man, machine, method, and material) against the actual requirement.
This is the excessive burden/load/stress that we create on machines, vehicles, and employees due to lack of knowledge, poor work instructions/practices.
e.g. Truck of 4 Ton capacity carrying 6 Ton material. Strain due to poor design, Operator getting over-tired by working in strained posture, Increased workload due to shortage/non-availability of manpower.
Countermeasure: Follow Ergonomics on workplace-minimum arms movement, head movement, and body movement, Follow standard operating system-SOPs.
