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Gaskets are used to provide sealing in bolted joints that function under a wide range of assembly and loading conditions. Tolerance distributions of the gasket and flange components as well as assembly load variation will cause the gasket sealing stress to vary. In some cases, this variation is significant. In these cases, gasket designs based on nominal dimensions and loads may not function properly unless one or more engine test and design modification cycles are carried out. A probabilistic technique has been developed to evaluate gasket designs under a range of assembly conditions. The output is a prediction of the statistical distribution of key dimensions such as compressed thickness or parameters such as percent compression. Analysis of these distributions can be used to determine the number of occurrences where a gasket design would be expected to function improperly.

A bolted joint mathematical model is presented which includes flange bending effects. The approach simulates the behavior of a system of elastic flanges, a one component non-linear gasket, and linear elastic bolts subjected to assembly and pressurization loadings. Flange distortion is introduced to the joint diagram to predict the overall, midspan, and under the bolt gasket loads.

An embossed single layer of rubber coated metal is a technology that is being applied to the sealing of gasketed joints in internal combustion engines. This technology has the stability of steel, the sealability of rubber, and the control of stiffness through emboss geometry. The sealing performance of this technology is a function of many parameters involving material properties, gasket geometry, surface finish, and joint loading. The relationship between coolant sealability and these parameters was measured. In this paper, results are presented for half emboss configurations where emboss height, surface finish, and clamp load are varied. The data shows that emboss height and flange surface roughness have little effect on the sealing performance of the material studied. The data can be used to select gasket designs which require less expensive flange finishes and lower assembly loads while providing good sealing performance.