APPLICATION OF TOOLS AND METHODS WITHIN LEAN MANUFACTURING. Miroslava MĹKVA, Marta KUČEROVÁ, Pavel VEČEŘA

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1 APPLICATION OF TOOLS AND METHODS WITHIN LEAN MANUFACTURING Miroslava MĹKVA, Marta KUČEROVÁ, Pavel VEČEŘA Slovak University of Technology in Bratislava, Trnava, Slovak Republic, EU, Abstrakt Lean Production or Lean Manufacturing - is a systematic approach that identifies and prevents waste by a continuous improvement of production processes. Waste, in this context is understood as all activities that do not bring additional added value. The article describes the different tools and methods that can be used for elimination or elimination of waste in the workplace. Keywords: Lean production, wasting, tools and methods 1. INTRODUCTION If an organization wants to succeed and be competitive, it must be focused on the customer, it must be flexible to respond to all needs and requirements, such as rapid and unexpected changes in the market. Basically speaking, the organization must provide its customers with high quality products. Quality has thus become one of the key means of a competitive struggle. One of the ways to ensure the quality of products or services is to implement a quality management system according to standards ISO The co-part of this International Standard is constant improvement. At present, we can say that if an organization does not improve, it is like it does not exist. Improvement can be realized in different ways. One way is via small steps of improvement, marked by the word Kaizen, or via rapid improvement, known as reengineering. The Quality Management System uses several tools and methods to improve its operations. In this paper we will discuss the improvement via lean manufacturing. 2. IMPROVEMENT THROUGH LEAN MANUFACTURING Improvement issues related to the development of the global economy gain big importance and is in the forefront of strategic thinking of managers aspiring success in today's demanding markets. Improving the quality should be seen as activities aimed at enhancing the ability to meet customers` requirements and expectations. Meeting the customers` requirements and expectations cannot be understood only in a condensed plane of technical specifications, but the quality is absolutely necessary to understand in connection with such factors as productivity, flexibility, delivery dates, and the minimization of costs. Management has constantly looked for opportunities to improve the efficiency and effectiveness of the processes of the organization, not waiting for a problem which reveals the opportunities of improvement. Improvements may cover a range from small continuous operations to strategic long-term projects of improvement. [1] One possible improvement is the improvement through lean manufacturing. The concept of "lean manufacturing" (lean production, lean manufacturing) comes from the Toyota company, where it originated in the 50 s to 60 s of the 20th century as an alternative to mass production in the environments that require a high level of flexibility and there was a lack of funds for costly investments. During that time the company's management was solving the low productivity of Japanese workers, which was a third of the total number of

2 German workers and a ninth of the American workers. From the idea of removing the useless, the later Toyota production system was born, based on lean manufacturing. [2] Lean Production is a systematic approach which identifies and eliminates all forms of waste from production processes and gradually reaches a synchronized production flow. This includes elements such as value stream mapping, lean workplace, process improvement (kaizen), visualization and standardization of processes, processes of quality assurance at source, manufacturing cells, total productive maintenance, fast casting equipment, teamwork and more. [5] Fig.1: Lean production [5] Lean manufacturing is so concentrated on the elimination of waste in any part of the production. Starting with contact with the customer and accepting his demands, continuing through the supply network, manufacturing process and ending with selling the finished product to the customer, flexibly, economically but at the same time respecting the customers needs. This does not mean that it is self invested reduction of costs. It is all about maximizing the added value to the customer. By the lean manufacturing philosophy, we try to eliminate any waste, called in Japanese - muda. The term muda refers to those activities that do not add value. Muda at a workplace has seven categories [4]: Muda of over-production, when a greater production of products is produced then it is required by customers. Overproduction leads to wasting of materials, energies and human work. Muda caused by unnecessary stock- this type of wasting is caused due to overproduction and purchasing for storage or storage of spare parts, not finished goods and finished goods. These items unnecessarily take space and require additional costs. Muda caused by defects Whenever defects occur, extra costs are incurred reworking the part, rescheduling production, etc. Muda caused by unnecessary movement of employees connected with the efficiency of their work causing a waste of physical power e.g. when removing staff to get spare parts Muda caused by inappropriate processing, use of the wrong technology can cause the deficit because of long production launching times and long working operation times. Muda caused by waiting wasting in consequence of lack of components, consumables and equipment or because of a damaged machine or unstable production Muda caused by transport transport is an inseparable part of the production processes which cannot be removed, however it does not give any value to the final product and this is why the aim is to reduce it to the lowest possible level

3 2.1 Principles and methods of lean production Principles of lean production: We know 5 basic principles of lean production [3]: 1. Understanding the value of the customer s perspective, it is necessary to know what is real value for the end customer and it is important for the organisation. 2. Analyse of the value stream-as soon as we understand the value as it understands the customer it is important to properly define the value flows (again from the perspective of customer) in the production process. It is necessary to determine the steps that add value and to eliminate those which do not add value. 3. Continuous flow- wherever possible it is necessary to establish a fluent flow of material without unnecessary stores and semi finished production. 4. Application of a tension system- an organisation does not produce to create stock; the production is subject to the requirements of customer. 5. Perfection- it is necessary to reduce or completely eliminate wasting, creation for the end customer should be equal or greater than his expectations. Tools and methods of lean production To eliminate sources of wasting, within the concept of lean production, various tools and methods are used that serve not only for searching difficult parts but also to remove them. Individual tools are interdependent; often the success of the implementation of one tool is conditioned to the implementation of another tool. Tools and methods can be divided into several areas (Fig. 1): Value Stream Mapping: identifies processes and process steps, adding value to the product from the customer's perspective and shows us the processes that do not add value and displays the processes that need to be eliminated; optimization of material and information flows - process maps, optimization of production deployment - layout, reducing of stocks and intermediaries, introduction of Kanban - replenishment of stores according to need.; SMED (Single Minute Exchange of Dies) - method ensuring the flexibility of production so that it can be able to produce, in small amounts, according to actual requirements of customers; methods for improvement of product quality - Poka - Yoke, PDCA, Kaizen, Just-In-Time, Six Sigma, and the like. The next section describes the selected tools that are most often applied in Slovak organisations. We approached this on the basis of long- term experience of the analysis of individual organizations that are performed by students' final papers and on the basis of a survey, which we conducted in the framework of the research project. Kaizen This is the most popular method of continuous improvement based on the creative thinking of workers. Kaizen philosophy is based on two words that describe the significance of this method: KAI - Improvement (everything can be improved, each product, work activity, production system) ZEN - Improvement is constant, it reacts to each new opportunity, changing of conditions, and each operative can participate in it. Kaizen means improvement in the production, focused on customers, improvement of all processes in the value chain of business activities with concurrent cost reduction. Its base is a mass initiative of operatives supported by an effective staff motivation system. The overall effectiveness of the management of the company is based just on the achieved productivity of work, which is monitored through staff performance. Due to this fact, it can be stated that the Kaizen method is focused primarily on operators and their performance, because the operators are co-creators and bearers of the company values. The aim of this method is to eliminate the faults, which Japanese managers call as "3MU" (MURI, MUDA, MURA). [8]

4 Just in Time The concept of production management Just in Time was created and applied in the management of production since the early seventies in Japan, the USA and Western Europe. It shows Effort primarily the effort to eliminate wasting throughout the whole production process, from the purchase of materials and semi-finished products, to the distribution of finished products. Production using the principles of Just-In- Time means to produce required types of products in the required quantities, in a required time, while ensuring "one hundred percent" quality, so that it is possible to remove the reasons for which the inventory must be maintained. [6] TPM - Total Productive Maintenance TPM focuses on the involvement of all employees in activities that aim to minimize disagreements and misfits. It is also about overcoming the traditional way of dividing staff into who works on the machine and who repairs it. It is considered that the worker who operates the machine has a chance to capture abnormality in his work and potential sources of future equipment failures via TPM operational teams in the workplace. [9] Method of 5S improvement 5S method comes from Japan. It was first implemented in the Japanese automotive industry, where it was used to support Lean management tools. This method represents the introduction of high-efficiency, order and cleanliness in the workplace. The workplace may be a workshop or it may be something that does not manufacture components for the organization - office. By using the 5S we identify unnecessary waste in the organization and then it is easier to detect problems in the workplace. The workplace is safer and easier to organize, workers perform their jobs more effective in a clean environment, stocks are smaller and this allows faster control. [7] F i g. Fig. 2: Sequence of steps during 5S method (online) The 5S method is based on the assumption that the organization, order, cleanliness, standardization and discipline in the workplace are essential conditions for the production of high quality products and services. It is characterized by little or no waste and high productivity. 5S Methodology stands on several basic principles [7]: the cleaner a workplace is the sooner problems can be identified, a cleaner workplace is more safe, a frequent and well organized environment is more predictable, workplace organization is simpler and visually clearer if the workplace is clean,

5 standardization and workplace organization enables faster responses stock levels are easier to control, communication on the state of manufacturing is easier. The 5S method is the application of the 5 steps following each other (see figure 2). [7]: 1. Seiri (Sort): department of unnecessary things in the workplace and their removal 2. Seiton (Stabilize): the arrangement of all the things that remain in the workplace after the first step in a transparent manner, 3. Seiso (Shine) maintaining a clean working environment, 4. Seiketsu (Standardize): implementation of standards and the continuous implementation of the previous steps 5. Shitsuke (Sustain): building self-discipline. In the frame of research task solving, in which we discussed the application of quality management in various sectors of industrial practice, we have investigated the application of different methods and tools that organizations apply in their practice. In the questionnaire survey, which involved 128 organizations, we have investigated the methods and tools applied in improving processes at different stages of the product within the PDCA cycle. Results of the 5S method are shown in Fig. 3.In the questionnaire; we have also investigated the application of "3MU" in individual organizations. Unfortunately, this question remains unanswered, whereby we assume that it has probably not been clearly established as to what is going on, or the organizations do not know how to address weaknesses under this name. 2.2 Lean production in relation to other concepts Along with the concept of lean production other concepts are also applied in the organizations, especially the Theory of Constraints (TOC) and Six Sigma methodology. The next section describes what the concepts add to each other [5]: Lean focuses on the systematic elimination of waste from business processes and the maximizing of added value. TOC focuses on a systematic search of bottlenecks in the enterprise, the maximizing of flow and the minimizing of stock and operating costs. Flow is basically the added value created in the process per unit of time. Lean and TOC thus have a tendency to maximize the speed of making money in the processes. Focusing on the bottleneck is very important in the deployment of elements of the lean enterprise. Lean, Six Sigma and TOC are looking at the business through the eyes of the customer and try to meet his requirements for minimum costs. Six Sigma seeks to systematically reduce process variability and to increase their yield. It is about stabilizing the times and other parameters that are necessary to synchronize business processes in a slim company. Six Sigma and TOC provide a sophisticated system for managing changes, which is usually provided by the Lean Hoshin Kanra system. In Six Sigma is a sophisticated project management system and the system of problem-solving DMAIC. In the TOC is a sophisticated system of logical analysis of

6 problems and their causes, conflict resolution, defining objectives and constraints, preparation of an action plan and project of change (thinking process), and a system of continuous improvement. The mutual interrelated of concepts is shown in Fig. 4, where it is seen that all of these concepts are important to the customer. At the beginning it is important to define the exact requirements of our customers and that then end customers are mostly satisfied. Fig. 4 Lean, Six Sigma a TOC [5] 3. CONCLUSION The aim of the article is to show the lean production as a form of improvement in organizations. The system of lean production focuses on the elimination of waste in any activity within the organization. No organization manages only with the lean production, but leaning has to be gradually transferred to all activities, therefore the concept of a lean enterprise appeared, and also the concept of lean thinking. A Lean Enterprise is mainly created by people, their potential, knowledge, self-realization and motivation for continuous improvement of processes. Continuous improvement is the goal of every organization. LITERATURE [1] PAULOVÁ a kol.: Perspektívy rozvoja manažérstva kvality v súvislosti s požiadavkami trhu Slovenskej republiky. 1. vyd. - Trnava : AlumniPress, s. - ISBN [2] BORDÁS, Robert: LEAN company Historie [online].[cit ]. Dostupné na internete: [3] KOVÁČOVÁ, Ľubica: Porovnanie štíhlej a agilnej výroby [online]. [cit ]. Dostupné na internete: [4] BEŇO, Rastislav: Plytvanie (Muda) na pracovisku z hľadiska ergonómie. In: Nové trendy v manažérstve kvality [elektronický zdroj]: 4. ročník medzinárodného vedeckého seminára, apríl 2011, Trnava- Trnava: AlumniPress, ISBN S [5] KOŠTURIAK Ján: Štíhly podnik móda alebo nevyhnutnosť? [online]. [cit ]. Dostupné na internete: [6] MIČIETA B.: Prosperujúci podnik. Žilina: Slovenské centrum produktivity, 2000, ISBN [7] SINAY, J. a kol: Nástroje zlepšovania kvality. Prešov: ManaCon, 2007, ISBN [8] TEPLICKÁ Katarína: Kaizen kvalita versus 3 MU [online]. [cit ]. Dostupné na internete: [9] KOŠTURIAK, J., FROLÍK. Z., Štíhlý a inovativní podnik. Praha : Alfa Publishing, s.r.o., 2006, ISBN