Methods for Determining the Reliability Indicators of Corrugated Perforated Sifting Surfaces

The primary objective of this study is to investigate and substantiate methods for analysing the reliability indicators of perforated sifting surfaces with different hole geometries applied in the separation of loose granular materials. Particular attention is given to the relationship between structural parameters of the sieve, the operating environment, and the mechanisms of wear that determine the service life of such components. The research is aimed at establishing analytical dependencies that link the geometry of perforated openings, material properties, and loading conditions with the degradation processes that occur during prolonged operation. In this context, the study addresses the fundamental engineering problem of extending the durability and operational stability of perforated sieves, which are widely employed in agricultural and industrial separation systems. The work presents a systematic analysis of basic flat sieves with elongated holes and modified surfaces with elongated holes reinforced by volumetric riffles. For both configurations, the influence of geometric characteristics, loading regimes, and external operational conditions on the wear dynamics was examined. Generalised analytical expressions for determining sieve wear were derived, taking into account structural dimensions, material resistance, and stress distribution caused by distributed loads from granular flow. Experimental investigations were carried out for two representative types of loose materials, wheat and corn, in order to validate the theoretical findings. A comparative assessment of wear coefficients was performed, demonstrating clear differences in degradation behaviour between the analysed sieve designs. Furthermore, the introduction of volumetric riffles was shown to effectively reduce localised stress concentrations, delay the onset of crack propagation, and extend the residual life of the sieve. The proposed methodological approach also provides opportunities for engineering optimisation at the design stage as well as for diagnostic assessment of sieve condition during operation. The conclusions highlight that the integration of volumetric riffles into the design of perforated sieves significantly enhances their wear resistance and prolongs operational reliability under varying technological conditions. The research outcomes confirm the effectiveness of the developed analytical expressions in predicting sieve degradation and allow engineers to perform comparative evaluations of durability for different structural modifications. The obtained dependencies for wear dynamics of sieves operating with wheat and corn illustrate the practical applicability of the method and demonstrate its potential for improving the performance of industrial and agricultural screening systems. Overall, the findings contribute to advancing the scientific basis for the rational design of perforated sifting surfaces and open up perspectives for further optimisation of their geometrical configurations in order to ensure increased efficiency, reduced maintenance costs, and improved sustainability of technological processes involving loose material separation.