Controlo Estatístico de Processo em Contextos “Short Run”: Modelo de Decisão
Controlo Estatístico de Processo em Contextos “Short Run”: Modelo de Decisão
Índice
1. Introdução
2. Revisão da literatura
3. Modelo de decisão
4. Caso de estudo
5. Conclusões
Para além de cada vez mais exigirem produtos com melhor qualidade e ao mais baixo custo possível, os clientes procuram também soluções com maiores níveis de personalização. Face a isto, as empresas industriais procuram adoptar sistemas de produção flexíveis, incluindo estratégias de personalização em massa, o que coloca novos e sem precedentes desafios em termos de procedimentos de controlo da qualidade a adoptar. O controlo estatístico do processo (SPC) abrange um amplo leque de métodos para monitorizar o desempenho de processos e detectar situações anómalas no seu comportamento, mas a sua utilização tradicional não fornece soluções adequadas ao exercício das actividades de controlo da qualidade durante a produção de pequenos lotes, no arranque de um processo, ou quando existe uma grande diversidade de artigos a produzir. Situações como estas encontram-se no âmbito da chamada produção de pequenas séries (“short-run”). Vários métodos de SPC têm sido propostos para lidar com diferentes ambientes de “short run”; cada um com as suas vantagens, limitações e especificidades. Este artigo fornece uma revisão da literatura completa e actualizada sobre o tópico, distingue diferentes classes de abordagens de SPC para pequenas séries e, a partir daqui, apresentar um modelo de decisão conducente à selecção do melhor método de “SPC short run” para uma determinada realidade. O modelo foi testado numa empresa têxtil e incorporado numa solução de software.
Pedro Alexandre Marques, licenciado (2001) e doutorado (2013) em Engenharia Industrial pela FCT-NOVA; Six Sigma Black Belt certificado pela American Society for Quality (ASQ); Consultor Sénior no ISQ – Instituto de Soldadura e Qualidade (2006-); Professor Auxiliar na Universidade Lusófona de Humanidades e Tecnologias (2014-); Professor Assistente convidado na Faculdade de Engenharia da Universidade Católica Portuguesa (2008-2012); Membro do Conselho Editorial de publicações nacionais e internacionais, incluindo o International Journal of Business and Industrial Marketing. Orador convidado em diversos eventos; Autor e co-autor de várias publicações, incluindo capítulos de livros; Coordenador do projecto vencedor do Prémio Equipas de Melhoria atribuído pela Associação Portuguesa para a Qualidade (2015); vencedor do Prémio Boléo Tomé para o melhor artigo publicado na revista Qualidade da APQ (2014).
António de Sousa Ribeiro, Mestre em Engenharia Electrotécnica pela Faculdade de Engenharia da Universidade do Porto, Diretor da SISTRADE, S.A. desde Julho de 2000. Participou em vários projetos de investigação, como por exemplo o MAPPLE e acompanhou os projetos PSI, PTI, I9Source e FADIS.
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Cartas de controlo; Controlo estatístico do processo (SPC); Modelo de decisão; Short-Run.
