The interaction of test methods and failure criteria
A specific example is given in which test methods influence the ability of a component to meet a failure criterion. The example is for self-pressurized products such as aerosol containers. The U.S. Department of Transportation (DOT) regulates aerosol containers with respect to acceptable temperatures and pressures of their contents as well as the minimum burst pressures of the containers. Experiments have shown that the burst pressures of the containers are a function of the test methods used to measure the burst pressures. The paper also presents a method to determine the temperature at which a two-piece aerosol container burst, provided that the bottom of the container can be found and it is not severely deformed by impact. While focusing on the specific examples of aerosols, the broader issue is the relationship between test methods and the results achieved, with the ultimate goal of safer engineering outcomes. The nature of various test methods and their relationships to how a mechanical system is likely to stop functioning properly and safely are also discussed. Aerosols present an interesting case study because they involve several disciplines and concepts and are very familiar to most people.
Keywordsaerosol burst pressure failure criteria test methods
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