Kalite geliştirmede yeni yöntemler ve uygulamaları

Abstract

Yeryüzünde büyük değişim rüzgarlarının yaşandığı son 50 yılda, bu değişim rüzgarlarından Türkiye' de etkilenmiştir. Küreselleşmenin bir sonucu olan değişimlerden etkileşim, son yıllarda teknolojinin de baş döndürücü bir hızla gelişmesi ile büyük bir sürat kazandı. Günümüzde değişimlere ayak uyduramayan kuruluşlar, kurumlar ve global anlamda da ülkeler çağın gerisinde kalmakta, rekabet edebilme gücünü yitirmektedirler. Rekabet edebilme sırrının artık müşteri memnuniyeti yani kalite olduğu artık tüm dünyanın bildiği ve kabul ettiği bir gerçektir. Bu yüzden firmalar müşteri memnuniyeti ve müşteri isteklerinin karşılanmasını sağlayacak şekilde mal ve hizmet üretimini gerçekleştirecek bir yapı oluşturmalıdırlar. Böyle bir yapının kurulması ise, Toplam Kalite Yönetiminde yatmaktadır. Bu yüzden bu kavramın çok iyi anlaşılması, benimsenmesi ve uygulanması gerekmektedir. Hatta pazarda lider olabilmek için firmanın bir adım önde olup, müşterinin gelecekteki beklenti ve ihtiyaçlarını öngörmesi / belirlemesi gereklidir. Yeni ürün tasarımı veya mevcut ürünün geliştirilmesinde, müşteri beklenti ve ihtiyaçlarının öncelikli olarak değerlendirmede ve tasarım prosesine dahil etmede başarılı sonuçlar getiren bir teknik olarak `QFD-Kalite Fonksiyon Açınımı` dikkat çekmektedir. Kalite Fonksiyon Açınımı ile müşterinin ihtiyacını karşılamada öncelik verilmesi gereken kalite karakteristikleri belirlenir. Bu aşamada müşteri taleplerinin çok yönlü bir şekilde algılanması ve hiç bir hataya meydan vermeden ürün ve hizmetlere dönüştürülmesi gerekmektedir. Hatasız ürün ve hizmetler, bir taraftan müşterileri memnun ederken, diğer taraftan da maliyetleri iniş trendine sokacak, böylelikle işletmenin var olma savaşına destek vereceklerdir. İşte bu noktada da `HTEA- Hata Türü ve Etkileri Analizi` işletmeler için kıymetli bir araç olarak ortaya çıkmaktadır. HTEA bilinen ya da olası hata türlerini belirleyecek, bu tür hataları önleyici ve/veya etkilerini düşürücü önlemler geliştirir. Üretim sisteminin hatalı ürünler de üretebileceğim kabul eden her kuruluş bunların tüketiciye gitmesini önlemek amacıyla bir ayıklama sistemi kurmak zorundadır. Böyle bir yaklaşımda süreç ve girdilerin daha iyi kontrolü ile hatalar oluşmadan önlem alınmaktadır. Bu noktada 'İSK- İstatistiksel Süreç Kontrolü` nün önemi anlaşılmaktadır. İstatistiksel Süreç Kontrolü süreç kontrollerinde, sürecin kontrol altında olup olmadığını anlamak, süreci etkileyen özel faktörlerin var olup olmadığım tespit etmek, süreçteki değişkenliği azaltmak, spesifikasyonların gerçeğe daha uygun bir şekilde tespit edilmesi gibi pek çok alanda yaygın bir kullanıma sahiptir. Tezin ilk bölümünde kalitenin dünü ve bugünü anlatılmıştır. Bugün gelinen noktada asıl hedef müşteri memnuniyetini sağlamaktır. Bu memnuniyeti sağlamak için firmalar rekabet ortamında varlıklarını sürdürebilmek için çeşitli yöntem ve araçlar geliştirmek ve geliştirilen yöntemleri dikkate almak durumundadır. Tezde müşteri beklentileri ile ilişki kurulan mühendislik özellikleri aynı zamanda süreçte numune alınan ve ölçüm yapılan kalite karakteristikleridir.Kalite Fonksiyon Açınımı bize müşteri beklentileridoğrultusunda hangi kalite karakteristiğinin daha çok önem arz ettiğini göstermektedir. Kalite Fonksiyon Açınımı sürecinde, kalite evinin kurulmasından sonra analize devam ederek tüketicinin beklentilerinin imalat süreçlerine taşınması ile Süreç Kalite Evi oluşturulmuştur. Burada en önemli görülen süreç üzerinde Proses HTEA çalışması yapılmış ve İstatistiksel Süreç Kontrolü ile bağlantı kurulmuştur.

Total Quality Management is a concept to improve quality of the production or services given by the company in order to fill the customer expectations. This concepts continuously worked in order to improve business process. Total quality is an approach to doing business that attempts to maximize the competitiveness of an organization through the continual improvement of the quality of its products, services, people, processes, and environments. The key elements of total quality.. Customer Focus. In a total quality setting, the customer is the driver. This applies to both internal and external customers.. Obsession with Quality. This means all personnel at all levels approach all aspects of the job from the perspective of `How can we do this better?` When an organization is obsessed with quality, good enough is never good enough.. Scientific Approach While it is true that people skills, involvement and empowerment are important in a total quality setting, they represent on a art of the equation. Another important part of the equation is the use of the scientific approach in structuring work and in decision making and problem solving that relates to the work.. Long term Commitment Organizations that implement management innovations after attending short-term seminars often fail in their initial attempt to adopt the total quality approach. This is because they approach total quality as just another management innovations rather than as a whole way of doing business that requires a whole new corporate culture.. Teamwork Internal competition tends to use energy that should be focused on improving quality, and, in turn external competitiveness.. Continual Improvement of Systems In order to continually improve the quality of products or services: which is a fundamental goal in a total quality setting: it is necessary to continually improve systems.. Education and Training Education and training are fundamental to total quality because the represent the best way to improve people on a continual basis. In a total quality organization, everyone is constantly learning.. Freedom through Control Involving and empowering employees is fundamental to total quality as a way to simultaneously bring more minds to bear on the decision making process and increase the ownership employees feels in decisions that are made. The freedoms enjoyed in a total quality setting are actually the result of well planned and carried out controls.. Unity of Purpose In order to apply the total quality approach, organizations must have unity of purpose. Collective bargaining is about wages, benefits, and working conditions, not about corporate purpose and vision. Employees should feels more involved and empowered in a total quality setting than a traditionally managed situation, but the goal of total quality is to enhance competitiveness not to eliminate unions.. Employee Involvement The basis for involving employees increases the likelihood of a good decision, a better plan, or a more effective improvement by bring more minds to bear on the situation on the situation: not just any minds, but the minds of the people who are closest to the work in quest. It also promotes ownership of decisions by involving the people who will have to implement them. Empowerment means not just involving people but involving them in ways that give them a real voice. To ensure uniformity of quality, it is necessary to have uniform standards. In this way, what is considered a quality product in one country will also pass muster in another country. This is an important aspect of international trade. To date the most successful attempt to develop an international uniform quality standard is ISO 9000. ISO 9000: a set of universal quality standards: provides a uniform framework for quality assurance that can be used worldwide. In effect, ISO 9000 has codified into a single system the essential principles common to diverse quality management and assurance standards. In a total quality setting, quality is defined by the customer. A reliable customer defines quality. The customer must be the organization's top priority. The organization's survival depends on the employee. Customer satisfaction is essential. Customer satisfaction relies upon meeting the needs of the customer which relies upon understanding the needs. And understanding the needs relies on knowing who the customers are.. Determine your external, internal, and residual customers. If you do not know who they are, you can never determine what they want.. Learn all you can about your customers, their needs, their wants, and their desires.. Determine specifically what customers expect from you. Then determine which of their needs your product or service can meet.. Identify the potential customer. This can provide a new perspective about what is important in your product or service.There are many strategies for understanding who your customers are. It isn't terribly difficult. It is simply important. Quality Function Deployment - QFD was developed to ensure that products entering production would fully satisfy the needs of their customers by building in the necessary quality levels as well as maximize suitability at every state of product development. It is an integrated approach to product development and quality in all production activities. QFD is actually a model for incorporating customer input and feedback into product development. It establishes an operational structure for the concept of building quality in. The underlying philosophy is that even a perfectly manufactured product may not satisfy the customer because it may be nothing more than a perfect example of what the customer does not want. To thrive in the worlds' business, growth and creating new markets is a critical strategy. And while growth can be achieved in many different ways- selling through different channels, selling more to existing customers, acquisitions, geographic expansion- nothing energizes a company more than creating new products. Quality Function Deployment (QFD) is a strategic planning technique for new product development. QFD is a team tool which captures customer requirements in the planning stages of product development. It provides a method for communicating planned product requirements into manufacturing. The origins of QFD come from Japan. In 1966, the Japanese began to formalize the teachings of Yoji Akao on QFD. Since its introduction to America, QFD has helped to transform the way businesses: - plan new products - design product requirements - determine process characteristics - control the manufacturing process QFD uses some principles from Concurrent Engineering in that cross functional teams are involved in all phases of product development. Each of the four phases in a QFD process uses a matrix to translate customer requirements from initial planning stages through production control. A QFD process involves: Phase 1 -Product Planning (The House of Quality) Phase 2-Product Design Phase 3-Process Planning Phase 4-Process Control Each phase, or matrix, represents a more specific aspect of the product's requirements. Binary relationships between elements are evaluated for each phase. Only the most important aspects from each phase are deployed into the next.Phase 1-This phase is usually led by the marketing department. Phase 1, or product planning, is also called The House of Quality. Many organizations only get through this phase of a QFD process. Phase 1 documents customer requirements, competitive opportunities, product measurements, and the technical ability of the organization to meet each customer requirement. Getting good data from the customer in phase 1 is critical to the success of the entire QFD process. Phase 2-This is product design phase which is led by the engineering department. Product design is where the creativity and innovation of the team are realized. Product concepts are created during this phase and part specifications are documented. Phase 3-Process planning comes next and is usually headed up by the manufacturing department. During process planning, manufacturing parameters are set in order to meet product design specifications. Phase 4-And finally, in the production planning, performance indicators are created to monitor the production process, maintenance schedules, and skills training for operators. Phase 4 is led by the quality assurance department. QFD is a systematic means of ensuring that customer or marketplace requirements are accurately translated into relevant technical descriptors throughout each stage of product development. Meeting or exceeding customer demands means more than just maintaining or improving product performance. It means building products that delight customers and fulfil their unarticulated desires. Companies growing into the 21st century will be enterprises that foster the needed innovation to create new markets. Failure mode and effects analysis (FMEA) technique is a systematic analysis technique which provides a means of identifying potential defects which could occur during product service. For industrial products, this analysis is carried out for both the design and the manufacturing process. That which distinguishes a Design FMEA from a Process FMEA is the subject of analysis: - Design FMEA deals with the component or part produced - Process FMEA deals with the various stages of the manufacturing process The two types of analysis are complementary, and are both intended to eliminate the causes of product failure occurring during customer use. Failure Mode and Effect Analysis (FMEA) is a technique to find the weaknesses in designs before the design is realised, either in prototype or production. The technique is an applied form of problem solving, and can be used in a large range of engineering disciplines.The FMEA Activities are designed to: 1. Recognise and evaluate the potential failure of a product/process and its effects; 2. Identify actions which could eliminate or reduce the chance of the potential failure occurring; and 3. Document the process. The objective of FMEA activities is to enhance the design process and provide greater assurance and satisfaction to the customer. FMEA' s when properly conducted will produce the following benefits:. Better Knowledge of the product. An FMEA uses a variety of experts to examine the product from all sides. Better knowledge of the product leads to its improvement.. Time Savings If failure modes and their causes are identified before prototype parts are made and assembled, much time can be saved testing poorly designed or built parts.. Cost Savings Poorly designed prototype parts are quickly replaced by better designs as the weaknesses are revealed. By eliminating poorly designed parts, the high cost of several levels of gradually improving prototype parts can be avoided.. Reduced warranty repairs and recall Improvements in design and manufacturing will reduce the number and severity of warranty repairs and product recalls. This will help to reduce the overall cost of the product, and improve the manufacturer's and product's reputation.. Quality The items listed above all add up to a better product. Products are better because of their quality. Customers are always looking for better quality and quality products result in an increase in customer satisfaction..History A properly conducted and documented FMEA provides a record of the developing design of the product. It prevents past mistakes from being repeated by well intentioned but inexperienced engineers. The record of problems encountered and the solutions found will be of great benefit at the next design phase. It is also a useful document for newcomers to the team, enabling them to quickly come to grips with the product and its characteristics. Statistical Process Control (SPC) is a statistical method of separating variation resulting from special causes from natural variation in order to eliminate the specialcauses, and to establish and maintain consistency in the process, enabling process improvement. The rationale for Western manufacturers to embrace SPC is not only to improve product quality and simultaneously reduce cost but also to improve their product image in order to successfully in the world's markets. Variation in any process is the enemy of quality. Variation results from two kinds of causes, special causes and natural causes. Both kinds can be treated, but they must be separated so that the special causes: those associated with the Five M*s: can be identified and eliminated. After that is done, the process can be improved, never eliminating the natural variation, but continually narrowing its ange, approaching perfection. It is important to understand why the special causes must first be eliminated. Until that happens the process will not be stable, and the output will include too much product that is unusable, therefore wasted. The process will not be dependable in terms of quantity or quality. In addition, it will be pointless to attempt improvement of the process, because one can never tell if the improvement is successful: the results will be masked by the effect of any special causes that remain. Many organizations do not have the in-house expertise in statistics that is necessary for SPC. As SPC is being introduced, and decisions are being made on where to sample, how much to sample, what kinds of control charts to use, and so forth, a good statistician is necessary to assure the validity of the program. If the organization does not employee such an expert, it should either hire one or retain the services of an consultant for the early phases of the SPC implementation. The danger inherent in not having statistical expertise is developing an SPC program that is statistically invalid: a fact that can easily escape non-statisticians. When that happens, the SPC implementation may send messages that make the process control situation worse than it was before. It is important that the initial design of the SPC program be valid. This requires someone with more than a passing knowledge of statistics. If there are any doubts, get help. There must be a management commitment because there will be start up cost associated with implementation. Only management can establish the production quality level. Second, SPC and the continuous improvement that results from it will transcend department lines, making it necessary for management involvement. Third, budgets must be established and spent, something else that can be done only by management. With SPC, the total-quality tools have a dual role. First, they help eliminate special causes from the process, so that the process can be brought under control. Only then can the control charts be developed for the process and the process monitored by the control charts. The second role comes into play when, from time to time, the control charts reveals a new special cause, or when the operator wants to improve a process that is in control.