Procedimento de estimação da confiabilidade dos resultados obtidos em sistemas de medição. Estudo de caso da confiabilidade do equipamento de medição do número de Swirl.

Abstract

The measuring systems are designed to achieve a capability according to the requirements from the end customer or engineering specifications. This capability must be maintained through preventive maintenance and calibration. This study presents a procedure, where the measurement system capability is determined using the MSA (Measurement System Analyzes). After obtaining the capability of the measurement system, its reliability is estimated, considering as failure the loss of the capacity obtained. Failure times are obtained in accelerated life tests using the temperature increase as an overloading. The failures times are extrapolated to use condition through the Arrhenius-exponential, Arrhenius-Weibull and Arrhenius-lognormal models. The MTTF (mean time to failure) is calculated to estimate the maintenance and calibration times for the measurement system. An application of the proposed procedure is carried out on a prototype equipment to measure the Swirl number developed with a new measurement technology faster and more accurate than others available on the market. The study evaluates the capability of equipment to measure the Swirl number and then estimates failure times to obtain the reliability of measurements obtained and the time required for their maintenance.