In the present competitive global markets, a manufacturing company’s survival depends on how rapidly it can respond to changing customer requirements. Currently, the industry standard is to produce the products exactly on time, in the required quantity and quality, and with the lowest cost to be competitive, while generating a certain profit for the company.
To achieve this objective, the company must pay special attention to reducing production costs and the costs of implementation of subsequent operations that add value to manufactured products, thus creating a value stream. The concept and practice that allows these improvements in production processes is lean manufacturing (LM), which began in the 1950s and refers to a series of methods, philosophies and tools to minimize waste and maximize production.
What is lean manufacturing?
In the world of manufacturing, most of the emphasis is put on operational efficiency. Lean manufacturing, also called lean production, was originally created by Toyota in the reconstruction period after the Second World War.
Lean manufacturing is based on the idea of eliminating or minimizing any waste of resources (workers, materials, energy, etc.) in the production value stream of the industry. Any resources, activity or task that does not add value to the product is considered waste. In lean manufacturing, this waste identification, elimination or minimization is considered at every level and each step of the manufacturing process – i.e., design, manufacturing, distribution, customer service and end-of-life disposal.
This article introduces you to what lean manufacturing is, the common lean principles, tools, methods and techniques used by manufacturers that have implemented lean manufacturing into their manufacturing processes, and what you need to do to excel.
Types of waste
The quintessence of lean manufacturing is the elimination of all types of ‘waste’ occurring in the manufacturing organization. The waste elimination or minimization leads to a shortening of the time between idea to finished product to the customer, increases productivity and reduces manufacturing costs. The implementation process of lean manufacturing requires the identification of ‘waste’.
In lean manufacturing, waste is classified into seven types: overproduction, inventory, errors and quality defects, waiting times, over-processing, unnecessary transport, and unnecessary movement.
Overproduction is the production of more products than required. It is the most dangerous type of waste because it translates into high costs in materials, energy and storage, and is the beginning of other wastes.
Inventories refer to the excess stock of raw materials and components, more work in progress and more finished products than the required minimum. Storages of inventories can lead to damage or destruction of materials/products.
Errors and quality defects are probable and have a negative impact on the quantity of completed products.
Waiting time is the time lost in waiting for a product. It may be workers, materials, information or tools in the manufacturing process, and it is a cost.
Over-processing steps are sometimes necessary to add value to meet customer demands. This waste is understood as spending unnecessary time on the implementation of customer demand and the use of complex and expensive technologies without rationalization.
Excess transport is unnecessary movement of materials, semi-finished or finished products within the company. This leads to larger production costs and increases the risk of damage to the product and transportation costs.
Unnecessary movement or non-value-adding motion results most often from the inadequate design of a product and the workspace layout.
The techniques, tools and principles of lean manufacturing offer systematic methods to organizations that can be utilized to minimize waste within a manufacturing system. It allows companies to reach operational efficiency to get ahead of the competition. Industry trends reflect that companies that have adopted lean manufacturing principles tend to be faster in their product development by up to six months and stay 35% closer to products’ target costs than their competitors.
There is an abundance of resources available online about techniques, tools and principles of lean manufacturing, and if you want to excel in the field, you can study these through online courses such as a master’s in lean manufacturing.
Lean manufacturing principles
There are seven fundamental principles of lean manufacturing, with waste management being one of them. In order to excel in lean manufacturing, understanding these lean manufacturing principles is essential for any organization. The seven principles are briefly explained below:
- Optimize the whole
The sequence of activities required to produce a product or provide a service to customers is known as the value stream. The value stream should be optimized to deliver as much value to customers as quickly as possible. In terms of lean manufacturing, this means that the company should create a seamless productive system on the shop floor as well as optimizing efforts across knowledge workers – engineers, developers, and others.
- Eliminate waste
As mentioned above, waste in lean manufacturing is anything that doesn’t add value to the product for the customer. This may be anything that needs investment in the form of money, time or even talent. It can include a process, activity, product or service. If it does not create any value for the customer, it is considered a waste.
Eliminating waste across the value stream helps the manufacturer to create processes that require less human effort. In addition, these new processes also need less space, lower capital, and less time to deliver products and services at less cost and with fewer defects.
- Build in quality
Lean manufacturing focuses on practicing the principle of ‘build in quality’ in the process and product for sustainable growth. This requires standardizing all practices and automating hazardous, tedious and repetitive processes to minimize human errors. This leads to error-proof value streams, reduces risks and time to market, and focuses efforts on creating value for the product.
- Deliver fast
The ‘deliver fast’ principle of lean manufacturing is that the faster delivery to customers provides quicker learning from customer feedback and a better ability to improvise and produce exactly what they want. Reducing development and manufacturing time and delivering new products or features quickly are essential for sustainability.
- Create knowledge
To optimize the whole process, the lean principle of ‘create knowledge’ is important. The organization creates, compiles and analyses the results of small incremental experiments and generates the learnings. According to the lean principle of create knowledge, there must be suitable infrastructure to properly document data and retain valuable learning, and utilize them to not repeat mistakes.
- Defer commitment
The lean principle of ‘defer commitment’ is based on utilizing up-to-date, relevant information available to make informed decisions. With this, lean manufacturers can have higher agility and the lean organization functions as a just-in-time system.
- Respect people
The ‘respect people’ principle is concerned with all stakeholders. The respect for the customer brings in decisions that will minimize waste; the respect for employees-employers creates an environment that allows everyone to give their best at work; and the respect for co-workers optimizes processes that allow everyone to contribute the most they possibly can.
Global manufacturing organizations often have people belonging to different cultures and backgrounds and speaking different languages. For creating a healthy, safe and innovative workplace, it is essential to keep respect at the forefront of every interaction. This way, organizations will be able to retain and attract the best talent in the field.
Methods and tools of lean manufacturing
Details about some of the lean manufacturing tools are given here. To excel in their use, you can pursue a master’s in lean manufacturing or utilize the online resources that are available. By learning these tools and methods, it is possible to excel in lean manufacturing.
- VSM (value stream mapping)
VSM is a tool widely used in manufacturing enterprises for graphically mapping material and information flow for a production system. VSM shows all the tasks undertaken in the manufacturing process, starting from the procurement of supply materials and finishing with the delivery of completed products to the customer. With this analysis, companies can identify all the types of possible waste in the process. They can also offer suggestions for further action in order to eliminate them. It is useful for identifying overproduction and inventories. For VSM, a software package is there, which is a visual lean tool to help organizations optimize manufacturing and production.
- 5S (Five S) method
Another method used for the analysis of production processes in lean manufacturing is 5S, which focuses on workstations. The name 5S comes from the first letters of the five Japanese words Seiri, Seiton, Seiso, Seiketsu and Shitsuke, which translate to organize, tidy, clean, standardize and sustain, respectively. It is a step-by-step method to increase productivity efficiency, improve safety and reduce waste. The 5S steps help to minimize multiple types of waste and are as follows:
Seiri (organize/sort): The first S implies eliminating clutter and unnecessary items from the workspace to ensure better use of the working space. Manufacturers can organize in such a way that movement is minimized, and all the tools and equipment are placed in areas close to where they’re required.
Seiton (tidiness/set in order): The next S states that “there is a place for everything, and everything is in the right place”. This will reduce unnecessary movements that may be performed when things are not in the proper place and will eliminate errors resulting from mistakes of using the wrong item.
Seiso (clean/shine): This S relates to cleanliness and sets out the standards to maintain clean workstations. Cleanliness can identify and eliminate the causes of machine and product failures, reveal any hazards, create a better working environment, and increase productivity. Safety at the workplace is directly related to workstation organization and cleanliness.
Seiketsu (standardize): Standardize all work processes and implement them so that any worker can step in and perform the job. This sets rules for the first three Ss. A standard systematic procedure ensures repeatability.
Shitsuke (sustain): The final S is the discipline to constantly maintain and reinforce the previous four Ss and act in accordance. It is considered difficult and long term because this requires changing the habits of both production workers and management.
The 5S method does not require a large financial investment, and it allows the creation of the working environment. It is the first step in giving employees a sense of ownership in the workplace. Implementing 5S reduces costs through getting rid of unused materials, tools and equipment, and organizing, which frees up space. Less storage space not only reduces space costs but also improves material organization and decreases the costs of cleaning, maintenance and space conditioning.
- TPM (total productive maintenance)
TPM is a tool that lean manufacturing uses to eliminate waste associated with manufacturing machines. It integrates all employees to maintain production continuity. It focuses on increasing the efficiency and productivity of machinery by a marked decrease in the number of failures, reducing short downtimes and idle time. The 5S system is the basis of total productive maintenance.
- Kanban
Kanban is a Japanese method of production control. To detect and avoid any problem in the process, lead time and cycle time are measured in different sections of the process. A digital Kanban board is a visual production system, a lean tool that helps visualize and improve processes so as to eliminate waste.
- Kaizen philosophy
Kaizen philosophy is the concept of continuous improvement, with a constant search for ideas to improve all areas of the organization. It requires the involvement of all employees and operators up to the highest level of management. In practice, Kaizen is collecting and implementing ideas of employees, which serve to improve the organization and the production process.
- Poka-Yoke
Poka-Yoke is a method of preventing errors arising from mistakes. It is considered as a tool that guides operators to avoid mistakes. It reduces or eliminates product defects.
- The five whys
This is a simple but effective thinking tool that helps to make sure that the true root causes are accurately identified.
- Andon
This lean tool is for visualizing information and empowering people to act upon that information.
In conclusion
Modern manufacturing value streams are more and more software-dependent, and lean manufacturing refers more to the deployment of knowledge workers, using lean principles to work smarter, innovate faster, and deliver more to customers. Lean manufacturing is making manufacturing companies more attractive places to work.
