International Journal of Mechanical Engineering and Technology (IJMET) Volume 8, Issue 7, July 2017, pp. 498–509, Article ID: IJMET_08_07_057 Available online at http://iaeme.com/Home/issue/IJMET?Volume=8&Issue=7 ISSN Print: 0976-6340 and ISSN Online: 0976-6359 © IAEME Publication Scopus Indexed A LEAN SIX-SIGMA MANUFACTURING PROCESS CASE STUDY Hari Supriyanto and Diesta Iva Maftuhah Department of Industrial Engineering, Faculty of Industrial Technology, Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia ABSTRACT Lean Six-Sigma – LSS is an approach that has been proven and applied in many manufacturing floor. Initiated in the automotive industry, continuous improvement were implemented to improve the manufacturing process change. LSS is used to elaborate a case where lean six-sigma principles can be adopted for the improvement process. Benefits of LSS are to reduce production lead time and to decrease work in process inventory. Six-sigma focuses on process flow and pressures to minimum variations. Value Stream Mapping-VSM is one of the lean tools used to recognize and to reveal problems lean, such as the sources of waste and find the hidden waste. VSM describes all activity of process, both value added and non-value added activity. Therefore, a new VSM is corrected to redesign a new lean process flow through process improvement with elimination of the root causes of waste. This paper proves the using of LSS principles and its application in case study for a product (gas stove). Key words: Lean Six-Sigma (LSS), Continuous improvement, Value Stream Mapping (VSM), Waste, Manufacturing. Cite this Article: Hari Supriyanto and Diesta Iva Maftuhah. A Lean Six-Sigma Manufacturing Process Case Study. International Journal of Mechanical Engineering and Technology, 8(7), 2017, pp. 498–509. http://iaeme.com/Home/issue/IJMET?Volume=8&Issue=7 1. INTRODUCTION Six-sigma concept was introduced by Bill Smith in 1986, a senior engineer and scientist within Motorola’s communication division in response to problem associated with high warranty claims. Six-sigma is a now widely applied program for company quality improvement. The first of organization to use six-sigma was Raytheon, Allied Signal, Polaroid, and Texas Instrument, but the amazing incident occurred after further developed by General Electric, in the mid. 1990s, and was followed by another organizations structure such as Sony, Dow Chemical, Bombardier and GlaxoSmithKline-GSK [1-3]. The success of the efforts at Motorola was not just achieving sig sigma quality level rather the focus was on reducing defect rate in process through the effective utilization of powerful and practical statistical tools and techniques. This would lead to enhance quality of service, improve productivity and customer satisfaction, reduced cost of operations or cost of poor quality, and so on. The quality improvement developed by Motorola can be seen in the http://iaeme.com/Home/journal/IJMET 498 [email protected] Hari Supriyanto and Diesta Iva Maftuhah following Table 1. Furthermore, six-sigma, as a quality improvement methodology, has gained considerable attention [4]. Application of the six-sigma methods allowed organization to sustain their competitive advantages by integrate the process with engineering, statistics and project management [5]. Numerous articles and books provide the basic concepts and benefits of the six-sigma methods [6-7]. Six-sigma applications in the service sector are still limited although it has been embraced by many big service oriented companies such as Lloyd, American Express, J.P. Morgan, ESB, Egg, Financial Services, Zurich, BT etc. The last decade has seen many service organizations such as Bank of America, Citibank, Caterpillar, Mount Carmel Health System and Baxter Healthcare in USA and Europe, success by sig sigma implementation [8-10]. Table 1 Motorola’s (six steps to six-sigma) Quality Improvement Manufacturing Non-Manufacturing (Manufactured Product) (Administration, Office, Service) 1. Identification of the product or service 1. Physical and functional identification from that is created and given to internal and voice of the customer external customers 2. Identify a product or service from the 2. Determine the essential characteristics of customer, and determine what customers the product consider important 3. Determine for each characteristic, whether 3. Identify your needs (including needs of it can be controlled by the process, part or the supplier) to provide products or controlled by both services so satisfy the customer 4. Determine the maximum coverage for 4. Define the process for doing work (a each characteristic process mapping) 5. Determine the variation on the process for 5. Mistakes-proof processes and eliminate each characteristic delays the work and efforts wasted 6. Always continuous improvements by measuring, analyzing, and controlling the 6. If the process capability (Cp) is less than process improvements (build quality and two then do improvements on materials, cycle time measurement and improvement products and processes required goals. Metrics commonly used is the number of defects per unit) Sources: Motorola Material, Fukuda The program presented in Table 1 describes that improvement action will be implemented in a project by project. It provides a clear organizational structure, in which improvement project are led by belt as black belt and green belt. To guide black belt and green belt activity, the program provides a methodology consisting of a collection of tools and stepwise strategy consist of five phase improvement cycle – DMAIC, within six-sigma companies has become increasingly common [11]. The goal of this paper is to review and examine lean and six- sigma practice and identify the key factors influencing successful lean and six-sigma. Therefore, this paper integrated lean and six-sigma project and potential applications in managing traditional projects. Wider application to the organization will succeed through senior management involvement, organizational commitment and culture change. 2. RESEARCH METHODOLOGY The six-sigma method is often imagined as the breakthrough with five phases of DMAIC: Define-D, Measure-M, Analysis-A, Improve-I, and Control-C. It represents a problem solving methods “specifically designed to lead a six-sigma black belt to significant improvement within a defined process” [12, 7]. Thus, the aim of this paper is to identify the issues facing http://iaeme.com/Home/journal/IJMET 499 [email protected] A Lean Six-Sigma Manufacturing Process Case Study and implement the lean and six-sigma in organization. In order to achieve the objective, the researcher used secondary data such as journals and documents, books, thesis, and scientific websites specialized in eliminating wastes. Two sources were used to collect the primary data. First, wastes identification was implemented through a brainstorming session with some managers to answer seven wastes questions. The illustration and analysis are based on literature review and the answers of the brainstorming groups. Second, a questionnaire was distributed to the management of all of the manufacturing division having more than some employee, and member of the research team offloaded and analyzed the results and resolution through the use of the statistical procedure. The data collection in this study involves quantitative and qualitative methods. Using this approach, information can be generated from the practical issues in implementation of lean six-sigma. Some qualitative data were set on ten point scale, where 9 = extremely important, 7 = very important, 5 = important, 3 = somewhat important, and 1 = not important. Furthermore, the last step is to determine the weighting to calculate the ranking of importance. 3. LITERATURE REVIEW 3.1. Six-Sigma Six-sigma is a systematic approach for improving manufacturing or service processes. Strengthen of six-sigma lies in its framework to facilitate the application of tools and techniques in a build data driven to support decision making [14-15]. The application of six- sigma was predominant in manufacturing process improvement. Recent developments show that its application is increasing in non-manufacturing operations such as transactional processes [16]. In order to apply six-sigma more broadly, need to introduce non- manufacturing that also involve processes. Identification of process parameters is one of the key to implementation of six-sigma in nonmanufacturing or service [17-18]. The success of six-sigma depends on certain success factors such as, top management commitment; tools and techniques; application of six-sigma methodology in DMAIC; and identification of KPIs such as financial impact measurement [19, 14]. Meanwhile, the statistical aspects of six-sigma must complement business perspective and challenges to the organization to implement six-sigma. Various approaches to six-sigma have been applied to increase the performance of different business sector. Integrating data and six-sigma processes in to organization still has room for improvement. Culture changes require time and strongly commitment before implanted into the organization [18]. Effective six-sigma principles and practices will more succeed by refining the organizational culture continuously. Six-sigma is a business improvement approach that seeking to find and eliminate causes of defects or mistakes in business processes by focusing on process output which critical in the eyes of customers. Six-sigma principles can be used to shifts the process average,