3M and 8 waste in lean manufacturing
3M is a Japanese concept derived to identify and eliminate non-value-added activities present in the manufacturing process. There are 8 types of waste in lean manufacturing. 3M waste is Muda, Mura and Muri. It is called 3M because the first letter starts with “M”.
Muda (waste), Muri (overburden), and Mura (disparity/variation)
Direct blockage of Muda flow as we know there are 8 specific types of Muda which all lead to waiting time and hence lead to longer time in a process. But only removing Muda does not work, usually Muda has to be removed with two of its companions and its two companions are Muri and Mura.
This means that the three enemies of LEAN are interconnected and therefore should be removed from the process together.
MUDA:- Wastage can be defined in 8 types that make up DOWNTIME.
D – Defect
O – Over production
W – Waiting
N – Non-Utilized Skills
T – Transportation
I – Inventory
M-Motion
E – Extra Processing
Defects: – Abandonment or rework of a product due to previously defective work or equipment results in additional cost and delay usually due to the following:
- Improper quality control during production
- Machine breakdown
- lack of proper documentation
- Lack of process standards
- Not understanding the need of the customer
- Incorrect inventory level
Over – Production: – Producing more of a product than it should be results in many forms of wastage, usually these are due to production in large batches. Customer requirements often change during the time it takes to produce a large batch. Over-production is said to be the worst kind of waste usually due to the following:· Incredible process·
- Unstable production schedule
- Market demand of production and lack of current information
- Not understanding the need of the customer
- Absence or malfunctioning of automation
- Longer set-up time
Waiting: – Whenever the product is not in transport or processed, it is waiting usually due to the following:
- Unplanned downtime or unnecessary machine shutdown
- Long or delayed set-up times
- Poor exchange of process information
- Lack of process control
- Output for a forecast
- Unnecessary shutdown of the machine
Non-Utilized Skills: – Often underutilize the skills that our colleagues working on the floor have or are allowed to work within their confines so that knowledge is not shared usually due to the following:·
- Poor exchange of information
- Failure to involve people in workplace design and development
- Lack of policies or inappropriate policies
- Incomplete measures
- Bad management
- Lack of team training
Transportation: – Every time any product is touched or moved unnecessarily there is a risk that it may be damaged, lost or delayed without any added value in the form of cost. Transportation does not add to the value of the product i.e. it is not a change for which the consumer pays usually due to the following:·
- Bad layout – large distance between operators
- Long haulage
- Large batch size
- Multiple storage
- Improper production system
Inventory: – Whether in the form of raw materials, work in progress (WIP) or finished goods, which represent a capital outlay that may not yet produce income. The longer the product remains in this condition, the more wasteful contribution it makes. Ensures smooth, continuous flow of work through each process to minimize excess inventory usually due to the following:·
- Over production
- Production delay or waste of waiting
- Inventory mismatch
- Excessive translocation
Motion: – Unlike transportation which refers to the damage and transaction costs involved in moving the product, here transportation refers to the damage and cost incurred while making the product. This can lead to increased wear and tear of equipment, stress and injury to colleagues working on the floor, or unnecessary downtime usually due to the following:·
- Poor work station layout
- Bad production plan
- Poor process design
- Equipment to be used in multiple processes
- Single operation
- Lack of production standards
Extra – Processing: – To do more than a product requires for end-customer results, which takes longer and costs more to produce. This also includes using components that are more precise, complex, and expensive or of higher quality than absolutely necessary usually due to the following:·
- Poor exchange of information
- Not understanding the customer’s needs·
- Human error
- Slow approval process or excessive reporting
MURI:- When operators or machines are used more than 100% to complete their work they become overburdened, for this safety, design of standards and steps of all standards should be taken care of.
MURA:- Fluctuations in customer demand, fluctuations in per-product process time, etc. come under this. When mura is not reduced then the possibility of mura increases.