Eight Wastes of Lean

Eliminating wasteful activities is one of the most important prerequisites for building a successful company. This concept is an integral part of Lean Thinking and it helps increase productivity.

Lean manufacturing is a methodology derived from the Toyota Production System that focuses on minimizing waste within manufacturing systems while simultaneously maximizing productivity. Lean aims at eliminating the three types of deviations that show an inefficient allocation of resources. The three types are: ? Muda (無駄, Waste) ? Mura (斑, Unevenness) ? & Muri (無理, Overburden)

Waste [Muda]

Waste is any action or step in a process that adds cost but negates the value. Muda takes into account the wastes and aims to integrate each step of production into a holistic, efficient process that reduces costs and improves overall revenue. The original seven wastes (Muda) was developed by Taiichi Ohno, the Chief Engineer at Toyota, as part of the Toyota Production System (TPS). The seven wastes are Transportation, Inventory, Motion, Waiting, Overproduction, Over-processing and Defects. They are often referred to by the acronym ‘TIMWOOD’. The 8th waste of non-utilized talent or ‘Skills’ of workers was later introduced in the 1990s when the Toyota Production System was adopted in the western world. As a result, the 8 wastes are commonly referred to as ‘TIMWOODS’

1. Transport

Transport refers to the movement of people, tools, inventory, equipment, or products further than necessary in between processes.

It refers: A cost incursion, Adds no value to the product, Wastes time and energy § Can end up damaging the products themselves. Excess transportation may be caused by: Poor layouts, Large distance between operations, Lengthy, or complex material handling systems. Working to a faster rate than customer demand, Multiple storage locations

Optimal Practices

Utilizing most efficient routes (most obvious route may not be most efficient)

Staging processes as close together as possible

Optimizing material handling systems and consolidate storage areas

Avoiding lengthy or complex material-handling systems Transport

2. Inventory

Inventory waste is stock in excess of the requirements necessary to produce goods or services ‘Just In Time’ Excess inventory increases lead times, consumes productive floor space, delays the identification of problems, and inhibits communication.

Excess inventory can be caused by: Over-purchasing, Inventory Build-up between Processes, Large Batch Sizes. Stagnant Materials

Optimal Practices

Purchasing raw materials only when needed and in the quantity

Reducing buffers between production steps

Adjusting the production process to create a smooth flow of labor

Observing the First-In-First-Out principle regarding stagnant materials

Creating a queue system to prevent overproduction.

Use Just-in-Time (JIT) inventory techniques Inventory

3. Motion

Any unnecessary movement of people, equipment, or machinery which includes walking, lifting, reaching, bending, stretching, and moving. It can include repetitive movements that do not add value to the customer, reaching for materials, walking to get a tool or materials, and readjusting a component after it has been installed. Wasteful motion is caused by: Poor Workstation Layout, Poor Workplace Organization, Large Batch Sizes, Reorientation Of Materials

Optimal Practices

Improving workstation layouts to prevent excessive walking, bending, or reaching Arranging methods to allow parts to transfer smoothly from one hand to the other Redesigning the workplace layout to allow for less reorientation of materials

Placing equipment near the production location

Putting materials at an ergonomic position to reduce stretching and straining.

4. Waiting

Waiting involves any idle time produced when two interdependent processes aren't completely synchronized. This can be caused by machines, products, people, and information that forces operators to wait or work inefficiently. A lot of our time waiting for various reasons that may include:

Previous operations running over their expected time

Deliveries failing to arrive

Unreliable people and machines

Poor Man/Machine coordination

Need for batch, instead of a single product, completion

The time required to rework a product

Optimal Practices

Designing processes to ensure continuous flow or single piece flow

Synchronizing processes (machine & human) as best as possible

Leveling out the workload by using Standardized Work Instructions

Increasing reliability of processes

Reducing downtime by improving efficiency

Developing flexible multi-skilled workers who can quickly adjust in the work demands

5. Overproduction

 Overproduction is to manufacture an item before it is actually required. As it is tempting to produce as many products as possible when there is idle worker or equipment time. Overproduction costs are high to a manufacturing plant as it not only prohibits the smooth flow of materials but actually degrades quality and productivity. This creates excessive lead times, results in high storage costs, and makes it difficult to detect defects. Overproduction works in two forms: Producing something before it is needed § Producing too much of a product, resulting in work-in-progress and surplus stock

Optimal Practices

Balancing Supply and Demand

Producing per actual demand rather than forecasted sales

Adopting Just-in-Time (JIT) manufacturing philosophy

Creating more reliable processes

6. Over Processing

Over-processing refers to doing more work, adding more components, or having more steps in a product or service than what is required by the customer. Which includes: Using higher precision equipment than necessary

Using components with capacities beyond what is required

Running more analysis than needed

Over-engineering a solution

Adjusting a component after it has already been installed

Having more functionalities in a product than needed

Generating more detailed reports than needed

Having unnecessary steps in the SOPs

The duplicate entry of data in multiple documents

Optimal Practices

Clarifying Customer’s standards and expectations ahead of time

Producing to the level of quality and expectation that the customer desires, and make only the quantities needed

Only performing the processes necessary to meet these standards and expectations Using appropriate processes (Avoid overly complex machinery or processes if possible) §

Standardizing best techniques for workers to follow

Setting clear specifications and quality acceptance

7. Defect

Defects occur due to variation in the standard operating process & leads to the manufacturing of product which is not fit for use, resulting in either Reworking or Scrapping the product. Both results are wasteful as they add additional costs to the operations includes Quarantining Inventory, Re-inspecting, Rescheduling & Capacity Loss, without delivering any value to the customer. Defects are caused by: Inadequate Training, Skills Shortage, Incapable Processes, Incapable Suppliers, Operator Error, Excessive Stock & Transportation

Optimal Practices:

Developing a world-class quality assurance program

Focusing on preventing defects rather than resolving problems post-production § Seeking for the most frequent defect and focus on it.

Designing a process to detect abnormalities and do not pass any defective items along the production process.

Standardizing work to ensure a consistent manufacturing process that is defect-free. Routine Training, Capable Suppliers, Reduce Excess Stock, etc.

Implementing a Poka-Yoke ("Mistake-Proofing") system to reduce defects

8. Unutilized Talent

This waste occurs when organizations separate the role of management from employees. In some organizations, management’s responsibility is planning, organizing, controlling, and innovating the production process. The employee’s role is to simply follow orders and execute the work as planned. By not engaging the frontline worker’s knowledge and expertise, it is difficult to improve processes. As people doing the work are the ones who are most capable of identifying problems and developing solutions for them. non-utilized talent includes: Insufficient Training, Poor Incentives, Not asking for employee feedback, Placing employees in positions below their skills and qualifications

Optimal Practices

Appropriate TNI & Sufficient Training to Employees

Talent Based Incentives

Routine employee feedback

Placing employees in positions as per their Talent, Skills, & Qualifications

The first step to reducing waste is recognizing its existence & having an effective process for identifying them Value Stream Mapping (VSM) is a Lean management method for analyzing the current state and designing a future state. It shows the flow of information and material as they occur. It effectively maps out the processes involved, displaying the relationship between production processes in a visual manner separating value-added and non-value-added activities

Using the VSM and start with the end customer in mind

Working backward from the end customer to the start of the production processes

Documenting instances of the 8 wastes in the processes and develop a plan for eliminating or reducing them

Continuing challenging the team to find more wastes and continuously improve your processes

Engaging with the front-line workers and elicit their ideas for improvement

As the team begins reducing efficiency they will gain more confidence in their problem-solving capabilities and over time reducing waste becomes a part of their daily routine Identifying and Eliminating the Wastes

References: Leanmanufacturingtools.org l leanop.com l en.wikipedia.org l leanmanufacturingtools.org l www.kainexus.com