The Seven Wastes

The Chief Engineer for Toyota during the mid-1900 was Taiichi Ohno. Ohno is given credit for creating the Toyota Production System (TPS) and creating the seven wastes.

Toyota defines waste as being three-form:

• Muri - Overburden
• Mura - Inconsistency
• Muda - Elimination of waste

Muri is a key concept in the Toyota Production System that relates to being overburdened. Muri generally refers to the unreasonable work that management places upon their workers and machines. Carrying heavy weights, performing dangerous tasks, and working at a significantly faster than normal pace, are all examples of Muri. Muri defines this work as pushing a person or a machine beyond their normal limits.

Mura focuses on the inconsistency and unevenness due to human error. Examples of Mura include scheduling conflicts, assembly line problems, and anything that hurts productivity. Typically mura can be directly traced back to human error. Mura is a key step in the Just In Time (JIT) Methodology.

Muda is the final phase in the Toyota Production System and is the most wide-spread concept of TPS. Management is in charge of overseeing Muda to ensure that waste is eliminated from the company. Management should be able to determine if there are deeper causes of muda that are formed during muri and muda.

Muda divides waste into 7 categories:

1. Over-production
2. Waiting
3. Transporting
4. Inappropriate Processing
5. Unnecessary Inventory
6. Unnecessary/Excess Motion
7. Defects

In order to obtain a greater understanding of lean manufacturing, it will help to look at the 7 wastes of muda in depth:

Over-production.

Over-production refers to producing more than what is needed. Far too often a company will manufacture an item before it is needed. Over-production is considered a waste because it costs the company money to produce it and it lowers the quality of the product if it sits on the shelf. Generally over-production occurs due to high changeover times, unreliable equipment, or the process is unreliable. Over-production results in higher costs for storage, excessive lead times, and it makes detecting the defects quite difficult. The solution for over-production is to stop producing materials and only produce what can be immediately sold or shipped. Poor information flow is another reason that over-production occurs, hence why communication is so important in the lean manufacturing process.

Waiting.

Waiting refers to the waste of goods that are not moving. As you already may be aware, much of a product's life is spent waiting for the next phase. The reason this is considered a waste is because the good should never be waiting. If they are waiting it is due to poor material flow, long production runs, or travel distances.

Transporting.

Moving your product from one location adds no value to your product. Many products are damaged or lost, casing a waste of money. Transporting also requires the use of material handlers, and this also adds no value to the product. This is one waste that is difficult to reduce or eliminate. Mapping the flow of your product may be one way you can gain a greater understanding of the transportation phase and learn how to reduce the costs.

Inappropriate Processing.

Several companies purchase high precision equipment to do a simple job. High precision equipment often leads to over-production of goods. This can also encompass using the wrong suppliers or the wrong process to do a job.

Unnecessary Inventory.

Excessive inventory is a direct result of overproduction and waiting. Having excessive inventory will lead to increased lead times, limited floor space, and poor communication. Too much inventory often masks problems from other areas as well. Generally an influx of inventory can be traced to poor communication and batch processing.

Unnecessary / Excess Motion.

This phase is often related to behavior-based safety. It is the unnecessary bending, stretching, walking, lifting and reaching of an employee. Often the motion is not due to the employees behavior, but the machine they are operating may be manufactured poorly and the employee is unable to turn a knob (or something similar) without using poor ergonomics. This waste leads to health and safety issues, which obviously lead to bigger problems.

Defects.

Defects in the manufacturing process are a tremendous cost to a company. Any small defect directly impacts your bottom line and effects inventory, scheduling, inspection, and other factors. A minor defect can cost your company more than the entire manufacturing cost to begin with.

For some companies who use the seven wastes, employees have been added as an eighth waste. Many companies do not employ their staff for their creative skills, only for their muscles and nimble fingers. Several organizations have learned that by capitalizing on their employees creative skills, they can eliminate some of the other wastes all together.

By evaluating the seven wastes, you can determine where your company is lacking and where you can reduce or eliminate waste altogether. Toyota implemented their TPS program and reduced costs and lead-time and improved the quality of their products. Now, Toyota is one of the world's largest companies.

Besides the 7 waste approach of Toyota, there are other approaches to lean manufacturing. Many companies have developed "tools" to assist in the identification and the elimination of waste. These tools are often called value stream mapping, the 5 S Methodology, and Kan-ban. The goal of all the approaches is to reduce waste; the only difference is how you go about achieving the goal and if you can successfully implement it into your organization.

The 5 S Methodolgy is widely used by several companies. The 5 S methodology is another philosophy used as a way to organize and manage the workspace and work flow in your business to improve efficiency by eliminating waste, improving flow, and reducing process variables.

The breakdown for the 5 S Methodology is as follows:

• Seiri - Sorting.
• Seiton - Straighten or Set in Order
• Seiso - Sweep or Shine
• Seiketsu - Standardizing
• Shitsuke - Sustaining

The other popular approach is a Kan-ban system uses visual aids to control the movement of materials between different work stations. The name Kan-ban referred to a Japanese sign shop that used a visual image on a sign to communicate the type of products that were sold. The Toyota Production System implemented Kan-ban into their transport container. It is a card that is attached to the transport and storage containers. The purpose of the Kan-ban card is to identify part number and the container capacity. There is other information on the card as well that provides easy, visual, signals to the employees.

Successful implementation will expose the quality problems which exist within the company and you will be able to identify how to reduce the waste the problems are causing. For some companies, the focus on waste reduction only looks at one small problem at a time instead of a system-wide approach. Depending upon which type of managers you have, both approaches can be successful and both will reduce or eliminate waste.

In the end, lean manufacturing is "focused on getting the right things, to the right place, at the right time, and in the right quantity to achieve perfect work flow while minimizing waste and being flexible and able to change." The concepts of lean manufacturing need to be understood, embraced, and appreciated by the employees who build the products. If the employees do the concepts, they will pass them onto the entire process and deliver the value to the product. Management is again the biggest factor in lean manufacturing.

Weak management will not understand how to implement the tools of lean manufacturing and it will not benefit anyone. Lean manufacturing is simple to understand and easy to do. It is all about making the work simple, easy to manage, and understandable for the employees.

If you would like to take an additional step in the lean manufacturing process, you can adopt the Toyota mentoring process called Senpai and Kohai. Senpai and Kohai are essential elements of Japanese age-based status relationships. They are similar to a family relationship, which is decided upon age. In western culture, Senpai and Kohai can be compared to the concept of a mentor.

This mentoring approach works like this: an older sibling begins a company and mentors their younger sibling; the younger sibling will eventually have enough insight to become the mentor to the older sibling. It is a process of "thinking up and down" the organizational structure. Employee A affects the steps of Employee B who affects Employee C and so on. This process has been taken by Toyota and it has helped their suppliers to improve their production as well. There is another mentoring approach which is similar to Senpai and Kohai; it is called "Lean Sensei". Lean Sensei encourages your company to seek out outside, third-party experts who will provide coaching, advice, and unbiased opinions to your company.

Implementing the seven wastes into your lean manufacturing process will take some time and a complete mindset change on your part and on the part of management to become successful.