Revision About Accelerated Testing And Application In A Software For The Data Graphics Analysis

This work presents a revision on different types of tests that are compatible with the nature of the data. They can be used to evaluate or to determine the reliability of equipment's and components in the different design stages of the design. The classification of the tests takes into account the type of censoring in the tests or the criteria to interrupt them. A classification of accelerated tests used in the industry is presented, along with the objectives and considerations of the most used models. Last of all, a software is presented for the processing of the accelerated tests data with constant stress and simple failure mode, for right censored data and with multiple censored data. The Weibull, Log-Normal and Normal distributions, combined with the most used models (Arrhenius and Inverse Power Law), are used. The software allows the processing of the accelerated tests' data by two methods: Minimum Square and Maximum Likelihood. The first offers the initial values to apply the method of Maximum Likelihood, and to assure the convergence of the Newton-Raphson method. The software offers graphs of residual, probabilities vs. time, stress vs. percentiles where it is possible to make an evaluation of the model of the distribution and of the variation or not of the failure mechanism. Statistical tests are used for the validation of the tests, allowing the possibility of using different confidence levels to accomplish the calculations.262/(1981) Rio de Janeiro. NBR-5462. Confiabilidade - Terminologia, , Rio de Janeiro, 17 p(1986) Rio de Janeiro. NBR-9320. Confiabilidade de Equipamentos, Recomendações Gerais - Procedimento, , Rio de Janeiro, 34 pBai, D.S., Optimum simple ramp- tests for the weibull distribution and type- I censoring. Stress (1992) IEEE Transactions on Reliability, 41 (3), pp. 407-413. , SeptCondra, L.W., (1993) Reliability Improvement with Design of Experiments, , Marcel DekkerHamada, M., Using statistically designed experiments to improve reliability and to achieve robust reliability (1995) IEEE Transactions on Reliability, 44 (2), pp. 206-215. , JuneHirose, H., Estimation of threshold stress in accelerated life- testing stress (1993) IEEE Transactions On Reliability, 42 (4), pp. 650-657. , DecKhamis, H.I., Higgins, J.J., Optimum 3-step step-stress tests (1996) IEEE Transactions On Reliability, 45 (2), pp. 341-345. , JuneLeemis, M.L., Beneke, M., Burn-in models and methods: A review (1990) IIE Transactions, 22 (2), pp. 172-180. , JuneLin, Z., Fei, H.A., Nonparametric approach to progressive stress accelerated life testing (1991) IEEE Transactions On Reliability, 40 (2), pp. 173-176. , JuneMeeker, Q.W., Escobar, L.A., A review of recent research and current issues in accelerated testing (1993) Int' 1 Statistical Review, 61, pp. 147-168Meeker, Q.W., Hamada, M., Statistical tools for the rapid development & evaluation of high- reliability products (1995) IEEE Transactions On Reliability, 44 (2), pp. 187-195. , JuneMeeker, Q.W., Hahn, G.J., How to plan and accelerated life test (1985) The ASCQ Basic References In Quality Control, Statistical Techniques, p. 10Nácer, C.A., Dedini, F.G., Uma revisão sobre ensaios acelerados e sua aplicação num programa para a análise gráfica dos dados (1998) V CEM-NNE 98, Congresso de Engenharia Mecânica Norte Nordeste, 1, pp. 33-40. , OutNácer, C.A., (1999) Accelerated Tests. Processing and Collecting of Data for Reliability Studies in Cases of Simple Failure Mechanism, , Campinas,: Faculty of Mechanical Engineering, State University of Campinas, 152 pp. Dissertation (MSc)Nelson, W., (1990) Accelerated Testing: Statistical Models, Data Analysis and Test Plans, , John Wiley & Sons, 230 pPallerosi, C.A., (1997) Confiabilidade: Metodologia de Ensaios e Normas, 2. , Campinas. Inédito. 279 pRamakumar, R., (1993) Engineering Reliability Fundamentals and Applications, , Prentice Hall International Editions. 482 pSotskov, B., (1972) Fundamentes de la Teoria y del Calculo de Fiabilidad, , Editorial Mir, Moscú. 261