Muda Mura Muri | 3M Wastes in Lean Manufacturing

What is Muda Mura Muri in Lean Manufacturing?

→ The 3M technique in Lean Manufacturing is mostly used in the Toyota Production System.

→ The 3M stands for Muda, Mura, and Muri. This is a Japanese Concept.

→ The goal of Lean Manufacturing is to deliver increased value to the customer with the help of eliminating all kinds of wastes from processes.

→ Now we will understand this concept with the help of examples and case studies.

What is Muda?

→ Muda means waste or we can say that any activity that consumes resources but not creating value for the organization or customer.

7 Types of Muda (Wastes) In Lean Manufacturing

→ The 7 types of Muda in lean manufacturing are mentioned below.

→ Refer to this article for a detailed presentation with the infographics of 7 Types of Wastes in Lean Manufacturing.

→ Nowadays one more waste is added into muda that is un-utilized talent or skill set.

Transportation
Inventory
Motion or Movement loss
Waiting
Overprocessing
Overproduction
Defective Parts

→ We can eliminate all these wastes with the help of Various Kaizen Activities.

What is Mura?

→ Mura means unevenness in any process or schedule.

→ Unevenness can be eliminated by Line Balancing or Level Scheduling for any process.

→ We can also say mura means variation or fluctuation in any process.

→ Sometimes there are many fluctuations in product demand so it will directly reflect on the production planning fluctuations. This is the very basic example of Mura.

➨ Refer to the below basic examples of Mura

⇢ Uneven Customer Demand

⇢ Uneven Production Speed

⇢ Uneven Work Load Distribution

⇢ Product Quality is not consistent

What is Muri?

→ Muri means overburden on the equipment or on the person.

→ In other words, we can say that if we are running equipment on a higher load for a long time that is called overburden or muri.

→ Also, if we tell the operator to work long period of time without taking any breaks that are also overburdened.

→ We can see this kind of wastes when the product demand is increased at that time machine and operators are working on overburden like in extra shift.

→ So it will create the problems like breakdowns, defect generation, etc.

➨ Refer to the below basic examples of Muri

⇢ Working in overtime or for a longer time due to uneven customer demand

⇢ Noise level is very high in the working area

⇢ The machine is running out of capacity due to high customer demand

⇢ Overloading of truck

Example of Muda Mura Muri Wastes:

→ Let us take one real-life example for understanding this concept.

→ One logistic company needs to transport 6000kg of material from Location A to B.

→ So there are many transportation scenarios that are possible, out of that we will take three different cases for understanding the concept.

Case 01:

→ Transportation company load 6000kg material in a truck and make a single trip.

→ But the truck's load caring capacity is 3000kg.

→ So it is Muri types of waste. It is overburdened on the truck.

→ So truck might be leading to breakdowns.

Case 02:

→ We can take a second case If the truck makes two trips of 2000kg in the first trip and the second trip of 4000kg.

→ This is the case of Mura because there is the unevenness of materials arriving at the destination location.

→ Due to the unevenness of material sometimes it creates problems of handling and storage.

→ Also, it is an example of Muri - overburden on an operator to multiple time loading and unloading activity need to do that is due to two trips instead of a single trip.

→ So these wastes are not adding any value to the supplier or customer.

Case 03:

→ In the third case, we make three trips of loading 2000kg material on a single trip.

→ So this is an example of underloading of trucks.

→ So it is a Muda means waste.

→ The only way to eliminate all types of waste we need to arrange two trucks having a capacity of 3000kg and make two trips of 3000kg each.