Quality Manufacturing Process
QUALITY MANUFACTURING PROCESS 1
Constantinescu Alexandru1,a, Dumitru Sergiu1,b National Institute for Research and Development in Mechatronics and Measurement Technique, Laboratory Automation of Complex Systems and Unconventional Control (MMI3), Sos. Pantelimon, Nr. 6-8, Sector 2, Bucharest, Romania a
[email protected],
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Abstract - The engineering of the manufacturing processes include both conceiving, designing and execution of the systems of manufacturing and being concerned of the quality of the products that will be done with these. The quality of the manufacturing process has a very important place today for large and small enterprises. This is reflected both through the implementation of processes and technologies of production, and by using a variety of sensors of visualization and control of processes. Ensuring quality processes in auto industry involves construction of some dimensional control systems of the parts for each manufacturing technology and the equipment where these are mounted or with which interacts. The field of application of these systems of quality checking is varied from the auto field up to areas such as the pharmaceutical, food, etc. In the auto field, where the quality of the manufacturing process represents an important component, it will present solutions for applications which target dimensional control of the parts used in the construction of motor vehicles. Analyzing dimensional control systems, the mode and the procedure, for their implementation, can be optimized for various parts of the same category, or similar control operations. Keywords: control, verification, auto, solutions, products.
1. Introduction The current industrial context and perspective is characterised through an accelerated dynamics of the manufacturing processes in the conditions in which the quality management exigencies have become a key focus. The increasing complexity of products and the expansion of markets is not possible unless it adopts the concept of quality assurance in all stages of the manufacturing process. In this context, flexibility of manufacturing processes has become a major target for cost reduction and the time required for change Manufacturing „in gusting”, with great diversity, as well as frequent introduction of new models/variants on the lines is a common fabrication processes. In this perspective, the implementation of the concepts of 'total quality', 'zero defects', 'prevention of errors', requires the application of the error-free systems as one of the solutions to satisfy simultaneously requirements for flexible process and strict quality monitoring. In engineering and industry, the concepts of quality and quality control are related to the development of systems that provide products and services that meet or even exceed customer requirements. Quality is a multidimensional concept that refers not only to products and services, but equally to the processes and activities of the business, its relations with its environment.
Quality production totaling the cumulative effect of the following factors: -the quality of raw materials which must comply with the specifications in the design documents; -the quality of the technology conception, resulting in the realization of product parts and subassemblies according to the design documents developed. Maximum reduction of „turns” that are time consuming from the manufacturing process and from the overall optimization of the product, it's a new way of organizing of the conception process of the production to ensure that the increase in productivity. This mode of approach of the development process of new products is called integrated engineering. The integrated engineering is the methodology that allows integrated conception of products and production processes and the associated maintenance. It aims to eliminate all the mistakes of any kind so zero defects and getting top quality products at the lowest price. The concept of the 'error-free systems' device was introduced in Japan by the term ' poka-yoke 'being used as an essential component in strategies of advanced quality management and Lean Manufacturing, Sigma, SMED (quick change of manufacturing).
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Quality Manufacturing Process 2. Quality manufacturing process Within the manufacturing process was pursued the study efficacy of the error-free systems in manufacturing processes and the opportunity of introducing monitoring operations through the embedded configurable integrated systems each workstation, interconnected in systems network coordinated by centralized management systems of the operations. It aims to study the possibilities of establishing integrated systems of every workstation on the production lines for the purpose of monitoring „the error-free systems”, as well as a network of interconnected systems-level production line and coordinated by a flexible software platform for the tracking of manufacture. In Bucharest, within the INCDMTM were designed and put into operation at SC Automobile Dacia Pitesti over 10 monitoring equipment for the error-free system of assembly operations in different assembly stations using solutions adapted to each particular station, which generated the idea of uniform treatment of the error-free systems to identify the mechanisms and implementing solutions to global industrial and in other areas of interest. The implementation of monitoring system for the error-free systems stations which are integrated in a production line is an ideal application for embedded systems. The analysis carried out on the characteristics aspects of error-free systems monitoring allowed the identification of the characteristic component modules present in all situations where the solution can be implemented using embedded systems: -module "identification" for customization in the diversity of concrete situations witnessed station; -module "signaling" to indicate operator for appropriate actions; -module "monitoring" concrete action for surveillance of the operator; -module "Control and Decision" for correlating information from other modules, implementing a decision on the (warning, stop) and communication with the higher hierarchical levels. As a result of the survey is highlights the crucial role it plays in the error-free systems continuous quality improvement processes, while reducing costs and increase flexibility of production processes. Also it can be concluded that the implementation of the processes characteristic classical concepts of type Lean c (with continuous quality improvement) by introducing widely of error-free systems can be achieved using modern technology with intelligent embedded systems without requiring additional human operator. In this way it maintains the concept of simplicity from the point of view of the operator using technical solutions with a high level of complexity.
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The automotive industry was the key element that led to the concepts development of continuous quality improvement (Lean Manufacturing) and where the error-free systems have a wide applicability. 3. Quality control The objectives are characterized by: miniaturization, flexibility, friendly user interface, modularity and interchangeability, reliability in operation and maintainability. The studies aim at establishing innovative solutions for identification of process/operation/phase using sensory techniques, smart materials, processing of images, virtual tags, embedded memories The necessary requirements were investigated for implementing a wireless network of adaptive modular systems in order to increase the flexibility and the safety Also an important objective of the activities was to clarify the issues related to the use of wireless networks in industrial environment in terms of security and robustness. Innovative solutions aim at the integration of existing activities to a higher level with the standardization and modularization, providing opportunities for application in other areas: security, health; handling; integrated management of drugs, opening a new area of application of information technology in the error-free control. Philosophical principles of Japanese 'kaizen' and 'poka-yoke', have been expanded and the car plants, thus integrating the philosophy of Oriental 'thing that sees the whole production space as a system, in which each process has direct consequences on the other'. The production of large or medium sized series require the contractors to perform various repetitive operations. Permanent and sustained attention to guarantee quality leads to fatigue and negligence. Physical memory of men, thoughtless behaviour, contribute to the drifting of the spirit, to 'fun'. In order to eliminate these inherent human weaknesses, it is necessary to equip the workshop with error-free systems. These error-free devices or systems can be presented in various forms. Thus in the engine assembly line were located about 10 posts in which the operators have to mount different parts depending on the type of engine, the automated systems that allow: -the bar code identification of the type of engine in the post; -optical signaling systems of shelves in a 'live storage' specially built for this purpose in which are found the appropriate type of engine subassemblies identified;
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Quality Manufacturing Process -flagging the correct (incorrect) action of the operator by the use of devices that it detects the presence of the operator's hand in the appropriate sheleves. It has also established similar systems for designated logistics service to prevent inadequate supplies of 'live storage' with subassemblies. In mounting workshop similar installations were placed to assist operators in various posts: -radiators and compensator mounting; -assembly/equipment of wheel in order to choose the weights used to dynamic balance; -mounting of dashboard; -selecting the appropriate car documentation depending on the geographical final destination of the car. A feature of the systems used in the general assembly line is the full identification of the vehicle situated in each post by using a computerized tracking system of manufacture which enables a dialog on the serial line with each post. An error-free system was also placed in piston mounting position post allowing the operator the choice of corresponding pistons depending on the measurement of specific dimensions. In cylinder head assembly line was installed an equipment that automatically determines the value of tappet clearance while assisting the operator for proper installation of these. Another type of error-free systems monitor the operator to the performance of operations in the appropriate order in the post and no omissions. One such system was installed at AutoChassisInternational, a leading provider of Automobile Dacia for checking the weld nuts on the rail. A system commonly used for detection of the presence/ position of holes on different parts and the fact that they are threaded or not. According to these, you can define the directions of modeling of wireless acquisition system In order to assess acquisition systems, performance indices are identified, among the basic cues included: the life, the latency, accuracy, mobility, network size (degree of connectivity, density), coverage, fault tolerance, network layout, scalability, robustness, QoS measurements, costs, etc.
Using the methods of identification of parts/phases/processes it aims to ensure their quality in fact, so avoid errors in manufacturing processes. Large scale software integration is specific to the analytical redundancy which is based on the notion of pattern. The system parameters can be identified on the basis of input and output, and then issue the conclusions about the existence or absence of defects. A process is considered to be efficient if it is able to provide facilities that meet quality requirements, to be more precise, if the number of scrap resulting from the process is practically null. By a technical process is done or change some characteristics of the product. Products may be in this case so rough, raw materials, intermediate or finished products and services. The result of a process (the outputs, the product) is influenced by means of influencing factors of the process. Preventing mistakes is better than their detection, and better than detecting defects. In a situation when a mistake is not detected and become defect, an additional processing is required (so called `return') or get a scrap. Therefore, we follow the manufacturing flow , as far as possible to detect or to control the mistakes before it gets to a fault. Similarly, it is more effective to prevent errors rather than to detect them. It is therefore appropriate that a trader to use all practical means to prevent, detect and correct errors that appear in the various stages of the manufacturing process of the products. In order to achieve effective control of quality, it should be keptunder control the variables that can affect the quality and that are the result of human action, the nature of the materials or equipment performance. Because on the main or causal reasons, the errors in the manufacturing process are not the guilt only of the people involved in the technical process. The result of a process, Figure 1 (outputs, product) is a function of staff working within the process, materials, and methods used, process equipment and the environment in which they work
Figure 1. Variables The Romanian Review Precision Mechanics, Optics & Mechatronics, 2014, No. 46
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Quality Manufacturing Process 4. Conclusions The long experience accumulated in projects developed in collaboration with the Automobile Dacia and with other enterprises in the automotive industry, during which specialists INCDMTM- Bucharest came into contact with a wide variety of situations where the conception and installation of error-free system allowed significantly reducing costs and increasing quality. Current and future industrial context is characterized by a accelerated dynamic of manufacturing processes in the condition where the quality management exigent has become a key concern In this context, the flexibility of manufacturing processes has become an important target for reducing the cost and time required for change. Critical analysis conducted and correlated with the experienced of our partners in the field have highlighted the opportunity to apply flexible and modular systems for monitoring the error-free system on the production flow lines, with great diversity, using wireless connected embedded systems. Were identified solutions, methods, embedded systems architecture with modular character for
monitoring and flexible cells with wireless connected error-free systems. This allowed the passage to the next stage of design embodied by the developing of effective execution documentation for the monitoring module. Manufacturers must meet the challenge of a competitive market in terms of price - quality. Quality levels that must achieve requires the use of video inspection systems. Companies are convinced that measuring parts in the primary stages improves product quality, not to mention reducing time control. Companies wishing to obtain maximum quality, should targeted the removal of the error. Although many techniques have been developed to prevent and control mistakes, they are largely ineffective. Effective Elimination of errors can not be achieved without a good understanding of their real characteristics. An error occurs when the required action is not performed or is performed incorrectly, it takes an action prohibited or essential information is not available or is misinterpreted. Eliminating error occurs when the approach do not comply with the steps from the figure 2.
Figure 2 Acknowledgment This paper has been financially supported within the project entitled „SOCERT. Knowledge society, dynamism through research”, contract number POSDRU/159/1.5/S/132406. This project is co-financed by European Social Fund through Sectoral Operational Programme for Human Resources Development 20072013. Investing in people!” 5. References [1] Dr. ing. Paun Anisoara*, Ing. Sergiu Dumitru**, Dr. ing. Vlăduţ Valentin*, Dr. ing. Găgeanu Paul**I.N.M.A.; ** I.N.C.D.M.T.M. Reducerea ,,întoarcerilor" consumatoare de timp din procesul de fabricaţie prin utilizarea sistemelor anti-eroare, Bucureşti;
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[2] Dr. ing. Paun Anisoara*, Ing. Sergiu Dumitru**, Ing. Anghel Constantin** Dr. ing.Vlăduţ Valentin*, Ing. Zaica Alexandru* -*I.N.M.A.; ** I.N.C.D.M.T.M – Sisteme de monitorizare antieroare înglobate pentru procese de fabricaţie- modul celulă flexibilă-modul monitorizare [3] Shigeo Shingo., Zero quality: source inspection and the poka-yoke system, ISBN 0-915299-07, 0-91529907-0 ,1986, Portland, Oregon [4] Mistake & erorr proofing -Managementul calităţii. Evitarea erorilor şi reşelilor “,,Către excelenţă prin performanţă” editia 2004 Quali AS [5] Draghici G. - Conceptia de noi produse, metode si mijloace, “Politehnica” University of Timisoara, Department of Manufacturing Engineering.
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