Toyota’s Chief Engineer, Taiichi Ohno identifies the following seven wastes while developing the Toyota Production System.
MUDA is a Japanese term which means that un productive or wasteful. It does not add value. An effective way to increase profitability is reduce waste. It is one of the key wastes adopted by Toyota in its Production system apart from Mura(Unevenness) and Muri (overburden).
1. Over Production
Over production is To produce Manufacturing too much sooner, too early or “Just in Case” faster or in greater quantities than the absolute customer demand. This discourages a smooth flow of goods or services, Takes the focus away from what the customer really wants, Leads to excessive inventory
What are the causes of Over Production?
Large batch sizes, Poor people utilisation, Lack of customer focus
What are the effects of over production
It Costs money, Consumes resource ahead of plan, Creates unnecessary inventory
Hides inventory/defect problems and leads to excess Space utilisation
2. Inventory
Excess inventory is defined as “Any raw material, work in progress (WIP) or finished goods which are not having value added to them”
what are the causes of this waste?
un even production schedule, Inaccurate forecasting, Excessive downtime/set up Large batch sizes and Unreliable suppliers
what are the effects of Inventory
It Adds to costs. It needs extra storage space. It takes extra resource to manage Can become damaged and losses due to expiry of shelf life
3. Motion
Motion in this context is the movement of “man”. Waste motion occurs when individuals move more than is necessary for the process to be completed
What are the causes of this waste?
The Main reasons are non availability of standard operating procedure, Poor housekeeping, Badly designed work area, Inadequate training
What are the effects
It adds to costs and increases the production time. It interrupts production. Can cause injury.
4. Waiting
This waste is defined as People or parts that wait for a work cycle to be completed
What are the causes?
Ineffective production planning, Shortages & unreliable supply chain, Lack of multi-skilling/flexibility, Downtime/Breakdown, Quality,design,engineering Issues. Shortage of capacity
What are the effects
Poor workflow continuity, Stop/start production, Causes bottlenecks, Long lead times, Failed delivery dates.
5. Transportation
Unnecessary movement of parts between processes
What are the causes?
It can be caused by badly designed process/work place, Poor value stream flow, Complex material flows, Sharing of equipment
What are the effects
It consumes resource & floorspace, Increases production time, Poor communication, Increases work in progress, Potential damage to products.
6. Over-Processing
This is defined as processing beyond the standard required by the customer
By improving processing efficiency we ultimately use less resource to achieve the same customer satisfaction
What are the causes?
Out of date standards, Attitude , Not understanding the process, Lack of innovation & improvement, Lack of standard operation procedures
What are the effects
It consumes resource, It increases production time, It’s work above and beyond specification, Can reduce life of component
7. Non-Right First Time (Scrap, Rework and Defects)
A defect is a component which the customer would deem unacceptable to pass the quality standard
Do it Right first time is the key
What are the causes
Out of control/Incapable processes, Lack of skill,training & on the job support, Inaccurate design & engineering, Machine inaccuracy,
What are the effects
It adds to costs, It interrupts the scheduled. It consumes resources .It creates paper work. Reduces customer confidence if it happens in field. Skipped deadlines.