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Publicação
Estudo da melhoria do desempenho dos processos de manutenção de embalagens de gases a alta pressão
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Resumo(s)
O presente estudo tem por objetivo a melhoria dos processos de manutenção de embalagens de gases de alta pressão. Em concreto, pretende-se melhorar a humidade no interior das garrafas e o processo de pintura da parte superior das mesmas, denominada ogiva. Com o objetivo de identificar modos de falha e as suas potenciais causas, foram realizadas duas FMEA (Failure Mode and Effect Analysis).
Na FMEA relativa à humidade, identificaram-se 212 modos de falha, dos quais 6,6% foram considerados muito críticos. Para a FMEA referente à pintura da ogiva, identificaram-se 90 modos de falha, entre os quais se verificou a existência de 17,8% muito críticos. Para cada uma das análises de risco, foram considerados 4 níveis de RPN (Risk Priority Number) médios.
Em relação à humidade contida na garrafa, o maior número de causas para os modos de falha está relacionado com o processo de secagem. Para tal, foram reconhecidas as oportunidades de melhoria. A influência das condições atmosféricas na humidade é relevante e propõe–se uma revisão do sistema para embalagens de produtos que têm uma especificação de humidade abaixo dos 10 ppm e o isolamento destas após a secagem, com maior importância nos meses de inverno. Adicionalmente, foi melhorada a dinâmica de secagem, através da implementação de peças de impacto de jatos e do isolamento da tubagem de ar quente comprimido.
A pintura da ogiva está associada ao tipo de gás que a garrafa deve conter. Averiguou-se que o maior número causas para os modos de falha está relacionado com a pintura da ogiva. Após a identificação das oportunidades de melhoria, desenvolveu-se um projeto para nova peça de proteção da gola da garrafa, com a sua implementação e estudo da sua viabilidade. Esta medida resultou na redução muito significativa da dimensão e do número de partículas de impurezas, particularmente, de granalha, o que se traduz numa diminuição clara da probabilidade de haver contaminação no interior da garrafa, bem como na facilitação de processos de finalização a jusante. Para a melhoria da pintura da ogiva, com base na medição das temperaturas ótimas de aplicação e na análise do processo, foi proposta a alteração do local da pintura da ogiva, na cadeia aérea automática, de forma que esta fosse a última etapa ocorrida e identificou-se a necessidade de aumentar a altura da banda de proteção da ogiva na etapa da pintura do corpo da garrafa.
This study aims to improve maintenance processes for high-pressure packaged gases. Specifically, the purpose is to improve the cylinder’s moisture content and the cylinder’s upper part, known as the shoulder, painting process. To identify failure modes and their potential causes, two FMEA (Failure Mode and Effect Analysis) were performed. In the moisture FMEA, 212 failure modes were identified, of which 6.6% were considered very critical. For the FMEA referring to the shoulder painting, 90 failure modes were identified, among which 17.8% were found to be very critical. For each of the risk analyses, 4 levels of average RPN (Risk Priority Number) were considered. In relation to the cylinder’s moisture content, the greatest number of causes for failure modes are related to the drying process. To this end, opportunities for improvement were recognized. The influence of atmospheric conditions on moisture is relevant and it is proposed a review of the system for packaging products that have a moisture content specification below 10 ppm and their isolation after drying, with greater importance in winter months. Additionally, the drying dynamics were improved, through the implementation of jet impingement nozzles and the insulation of heated compressed air piping. The shoulder painting is associated with the type of gas that the cylinder contains. It was found that the largest number of causes for failure modes are related to shoulder painting. After identifying opportunities for improvement, a project was developed for a new protective piece for the cylinder’s collar, with its implementation and feasibility study. This measure resulted in a very significant reduction in the size and number of impurity particles, particularly from shot blasting, which translates into a clear reduction in the occurrence of contamination inside the bottle, as well as facilitating downstream finishing processes. For the improvement of the shoulder painting, based on the measurement of the optimal application temperatures and the process analysis, it was proposed to change the location of this painting process, in the automatic chain, so that this was the last step that occurred, and it was identified that there is a need to increase the height of the shoulder protection band in the cylinder’s body painting step.
This study aims to improve maintenance processes for high-pressure packaged gases. Specifically, the purpose is to improve the cylinder’s moisture content and the cylinder’s upper part, known as the shoulder, painting process. To identify failure modes and their potential causes, two FMEA (Failure Mode and Effect Analysis) were performed. In the moisture FMEA, 212 failure modes were identified, of which 6.6% were considered very critical. For the FMEA referring to the shoulder painting, 90 failure modes were identified, among which 17.8% were found to be very critical. For each of the risk analyses, 4 levels of average RPN (Risk Priority Number) were considered. In relation to the cylinder’s moisture content, the greatest number of causes for failure modes are related to the drying process. To this end, opportunities for improvement were recognized. The influence of atmospheric conditions on moisture is relevant and it is proposed a review of the system for packaging products that have a moisture content specification below 10 ppm and their isolation after drying, with greater importance in winter months. Additionally, the drying dynamics were improved, through the implementation of jet impingement nozzles and the insulation of heated compressed air piping. The shoulder painting is associated with the type of gas that the cylinder contains. It was found that the largest number of causes for failure modes are related to shoulder painting. After identifying opportunities for improvement, a project was developed for a new protective piece for the cylinder’s collar, with its implementation and feasibility study. This measure resulted in a very significant reduction in the size and number of impurity particles, particularly from shot blasting, which translates into a clear reduction in the occurrence of contamination inside the bottle, as well as facilitating downstream finishing processes. For the improvement of the shoulder painting, based on the measurement of the optimal application temperatures and the process analysis, it was proposed to change the location of this painting process, in the automatic chain, so that this was the last step that occurred, and it was identified that there is a need to increase the height of the shoulder protection band in the cylinder’s body painting step.
Descrição
Palavras-chave
Secagem de garrafas Pintura da ogiva Embalagens de alta pressão Manutenção Gases industriais