Lean was originally developed as a manufacturing concept and, as such, is often referred to as lean manufacturing. However, as has happened with so many quality management-related concepts, the service sector—impressed with the results enjoyed by practitioners of lean manufactur- ing—began to adopt and adapt the concept to this sector. Consequently, we use the term Lean in this book to convey the message that the concept can be applied with good results in the manufacturing and service sectors. The purpose of adopting Lean as a business improvement method is to produce better products or deliver better services using fewer resources. If the concept had a motto, it would be this: doing more with less and doing it better.
1. Lean Defined
Lean as a concept is based on the Just-In-Time Toyota Production System (TPS) developed at Toyota Motor Corporation by Japanese quality pioneer Taiichi Ohno. Ohno’s work incorporated the earlier work of Sakichi Toyoda and Kiichiro Toyoda, the latter being the founder of Toyota Motor Corporation. Lean is a somewhat generic version of the TPS.24 A Lean operation is one in which a better product is developed or a better service is delivered using less of everything required (e.g., human, financial, technological, and physical resources). Lean is about being flexible enough to get the right things, to the right place, at the right time, in the right amounts. At the heart of the concept are the reduction of waste and the improvement of work flow. (For an in-depth study of Just-inTime and Lean, see Chapter 21).
The reduction of waste approach to Lean implementation grew out of Toyota’s desire to eliminate waste in manufacturing processes. Lean focuses on reducing and, ideally, eliminating the following types of waste:25
- Overproduction waste. This amounts to making more of a product or delivering more of a service than is needed or more than is needed at the moment. In a manufacturing setting, this might mean producing 100 parts when only 50 are needed. In a service setting, it might mean pumping 20 gallons of gas for a customer who wanted only 15.
- Inventory waste. This amounts to carrying more inventory than is needed at a given time. The concept ofjust-in- time deliveryhas the reduction of inventory as part of its broader purpose. In a manufacturing setting, this might mean having more parts stack up at an assembly station than can be used for a given production run. In a service setting, this could mean a bookstore carrying more copies of a given book than it is likely to sell.
- Motion waste. This amounts to incorporating unnecessary movement into the production process or into the delivery of services. This was one of the targets of the time and motion studies conducted by Frederick Taylor, who, in 1911, published the classic book The Principles of Scientific Management.In a manufacturing setting, this might mean programming too many motions into a CNC milling machine. In a service setting, it might mean having to move around the office several times to obtain everything needed to complete paperwork.
- Transportation waste. This amounts to excess movement of parts in a manufacturing setting. In a service setting, it typically means excess movement of people. In a manufacturing setting, this might mean that a part is machined at one side of the shop and must be transported all the way to the other side in order to be finished or incorporated as part of an assembly. In a service setting, it might mean having to transport patients to one end of a hospital for a given test and all the way to the other for another type of test.
- Overprocessing waste. This amounts to going beyond customer requirements in ways that create no additional value when producing a product or doing more than the customer wants in a service setting. A manufacturing example would be holding a given part to tighter tolerances than required in the specifications when the application of the part will not be improved by tighter tolerances. The classic service example is the sales representative who holds up a customer by continuing to talk after already making the sale.
- Defects waste. This amounts to creating rejected work or causing rework as the result of production or processing errors. In manufacturing, an example of a defect would be a part that is faulty because it does not meet customer specifications. In a service setting, it might mean having to rewrite an insurance policy because of calculation errors in writing the original policy.
- Waiting waste. This amounts to people, machines, or processes idling because something that is needed is not yet available. In a manufacturing setting, it might involve an expensive machine and its operator sitting idly because the parts they are to work on have not been delivered. In a service setting, the classic example is the airliner idling on the taxiway waiting for clearance to take off.
- Underutilization waste. This amounts to underuse of the talent, skills, and creativity of people and the capabilities of technology. In a manufacturing setting, it might involve failing to include the people who operate processes in brainstorming sessions aimed at improving the performance of those processes. In a service setting, it might mean using a sophisticated word processing system like it is just a typewriter with a visual display monitor.
2. Tools and Techniques of Lean
The tools and techniques of Lean will be familiar to students of quality management. In fact, most of these tools have already been explained at different places in this book. However, Lean is not just about the application of these tools. It is also about how they are applied and in what order. The tools and techniques most commonly associated with Lean are as follows:26
- Five-S workplace organization. The Five-S’s come from five Japanese words that translate into English as sort, store, shine, standardize, and sustain. Five-S as a tool is used to ensure a neat, clean, and orderly workplace, one that is conducive to peak performance and continual improvement.
- Visual workplace systems. This tool is used to promote ease of communication. It amounts to using visual aids such as signs, lines, labels, and color coding so that no one has to guess where to go or what to do.
- Layout. This tool is used to achieve the optimum plant layout so that motion and transportation waste are minimized. The idea is to get work that is input for another process as close as possible to that process to reduce unnecessary motion and transportation.
- Standardized work (SW). This tool is used to ensure that processes involving repetitive tasks are being done in the most efficient and productive manner and that all who operate the processes do them in the same way. This prevents the introduction of human and process errors.
- Point of use storage (POUS). This tool is used to ensure that the tools and parts needed at a given workstation are stored conveniently near that station. POUS helps minimize movement and transportation waste.
- Batch size reduction. This tool is used to achieve efficiency for the entire system rather than for a given process within the system. It helps ensure that work flows smoothly and continuously from one process to the next rather than bunching up at any given workstation or any part of a given process.
- Quick changeover (QCO). This tool is used to make process conversions as rapidly as possible. It might involve changing tools quickly in a manufacturing setting or changing a room for a different purpose in a service setting. Regardless, this tool helps eliminate time wasted in making process changes.
- Poka-yoke. This tool is used to error-proof a process to the extent possible. Poka-yoke is especially important for situations where there is the potential for human error. It amounts to asking the question “What could go wrong here?” when setting up a process and then finding ways to eliminate or at least minimize the potential errors identified.
- Self-inspection. This tool involves having personnel check their own work rather than just passing along errors to the next step in the process. In order to apply this tool, individual employees must be trained, provided with inspection standards, given the necessary inspection equipment, and allowed the time necessary to complete inspections.
- The word itself means “automation with a human touch.” This tool is used to build automatic alarms/process notifications into the system so that when a problem of any kind arises, a human being is notified and can intervene to solve the problem. For example, a robot that experiences some type of malfunction might shut down, thereby setting off an alarm that will notify a human operator of the need to intervene.
- Pull systems/kanban. This tool is used to provide a visual method—kanban is the Japanese word for “sign”— that lets one step in the process know that the next step is ready for its output. The sign or other type of notification is the “pull” that asks for the output.
- Cellular and flow. This tool is used to ensure a steady and consistent flow of work through the system’s cells. When the output of one cell in the process sits idly waiting to be used in the next cell, time is wasted. A steady, continuous flow of work is more efficient. This is the opposite of the old “hurry up and wait” phenomenon.
- Just-in-time (JIT). This tool is used to ensure that items are delivered to the next cellular step in the process just in time to be used. JIT is the antidote to work piling up at one station while another station has nothing to work on.
- Total productive maintenance (TPM). This tool is used to ensure that all equipment in a system and all parts of all processes that make up the system are in good condition and ready for use when called on. With TPM, equipment maintenance becomes a normal part of the process. TPM uses process operators in many maintenance procedures.
- Value stream mapping (VSM). This tool uses symbols to describe a value stream. It is implemented in four steps: (1) identify the process groups (of tasks), (2) develop a map of the current state, (3) develop a map of a desired future state, and (4) develop a plan to achieve the future state map. VSM is a continual process, since every process can and should be improved continually. This is the Japanese concept of
- Change management. Continual improvement is fundamental to Lean, and improvements do not happen unless changes are made. This tool is used to effectively manage change so that human resistance is minimized. An effective approach to managing change is as follows: (1) create a comprehensive word picture of how things will be different and better after the change (write it from the perspective of the process operators—those who will be affected most by the change and who will have to implement it); (2) communicate the change picture to all stakeholders; (3) give stakeholders opportunities to ask questions, make comments, voice concerns, and vent; (4) ask process operators to identify any roadblocks to successful implementation of the change that you might not have anticipated, and take the steps necessary to eliminate or mitigate these roadblocks; (5) implement, monitor, and adjust; and (6) incorporate the change into the process so that it becomes the normal approach until it is changed as the result of a subsequent process improvement.
- Teamwork. This tool is used to ensure that all other aspects of Lean can be implemented effectively. Lean, like all quality management concepts, is by its nature a team- oriented enterprise. The better teamwork is working in the organization, the better the results of Lean will be.
Source: Goetsch David L., Davis Stanley B. (2016), Quality Management for organizational excellence introduction to total Quality, Pearson; 8th edition.
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