Lean methodology originated from the Toyota Production System (TPS) which revolutionised the manufacturing of goods back in the 1950s, also known as Just In Time (JIT) production. Toyota encouraged employees to be part of the production process, such as introducing quality circles which was a group of workers who meet to discuss improvements in the workplace.
Lean is the relentless pursuit of IDENTIFYING & ELIMINATING WASTE in all of its forms in order to improve business performance and customer satisfaction and supports organisational excellence. Waste is categorized into 8 wastes;
Waste in Transport refers to the movement of people, inventory, tools and products further than necessary. Excessive movement of products and materials increases the risk of defects. Improving the layout ensure processes are closer together can help reduce transport or in an office environment, ensuring colleagues who need to collaborate should be closer together.
Having more inventory than is necessarily needed can lead to problems such as material defects, increased lead times, more time to find what is needed and problems can be hidden, such as detecting production-related problems as defects have time to accumulate before they are discovered, resulting in more time being used to correct these problems. Some countermeasures for reducing excess inventory can be to purchase raw materials only when needed and in the quantity needed and reducing buffers in between processes.
The unnecessary movement of people, equipment or machinery is defined as motion waste, such as walking, lifting, stretching, bending and reaching. Tasks that require excessive motion should be redesigned to enhance the work of the personnel and also improve the health and safety levels.
A well-organised work workplace is one of the countermeasures to reduce motion waste or placing equipment near the production area and materials in ergonomic positions to reduce the need for stretching or reaching.
The waste of waiting can include people waiting on material, equipment or idle equipment. An unevenness within the production processes can cause waiting times.
Designing processes to ensure continuous flow, balancing the workload and using standardised work instructions can help reduce or eliminate waiting.
5. Over Production
Manufacturing a product before it is required or being asked for causes overproduction waste. This can be easily done when a worker or equipment is idle or if the direction is to produce for a “just in case” situation which then can lead to more problems such as high inventory, resulting in higher costs for storage and preventing a smooth flow of work.
There are a number of countermeasures for overproduction, the use of “Takt Time” can ensure that the rate of manufacture between stations is even, reducing set up times to enable single-piece flow and small batches, using “Kanban” as a pull system to control the amount of WIP.
6. Over Processing
Adding more work, components or more steps in a process or product than what is required by the customer leads to the waste of over-processing. For example, using equipment that has higher precision than what is needed, running more analysis than is needed, over-engineering a solution or adjusting a component after it has already been installed. As a countermeasure, fully understanding the requirements from the customer in terms of quality, quantity and expectations and only working to these customers desires.
When a product is not fit for use, this is classed as a defect and results in components either being reworked or scrapped, both of which are wasteful activities as they add no value to the customer and increases costs to the operations. Collecting data on defects is key to enhance the use of Practical Problem Solving (PPS) to establish the “root cause” of defects and eliminate them from happening again. Also, the use of standardised work is important to ensure a consistent manufacturing process is defect free.
This 8th waste isn’t part of the original Toyota Production System (TPS), but many organisations are aware of this waste as unused human talent and ingenuity. By not engaging the front-line worker's knowledge and expertise, it is very difficult to improve processes as these are the people doing the work and are the ones who are more capable of identifying problems and developing solutions for them.
This waste can also be seen when employees haven’t been trained properly, given the wrong tools for the job and not being challenged to come up with ideas to improve the work. The use of a “Skills Matrix” is a fantastic tool that can determine the skills required for a process, or role and identify where the organisation needs to focus on training.
There are some general misconceptions of what Lean is by those that are less familiar with its principles and tools such as;
· Less Employees Are Needed – This is not the case, Lean thinking can maximise utilisation and output of employees by increasing value-added activity and employee development.
· A set of tools to provide a quick fix – Lean is about the long-term sustainable fixes.
· A top-down approach – The approach of Lean is equal across the whole business, from the shop floor up to management as team-based activities.
· A single event – A Lean journey is about continuous improvement that should never end.
Lean is essentially a continuous journey to systematically identify and eliminate waste (non-value-added activity). It promotes the relentless pursuit of perfection through a PDCA (Plan Do Check Act) cycle with the support of employee ideas and involvement.
Lean is a powerful and proven set of principles and methods which can be used in any environment and setting.