Abstract: The accurate prediction of the risk of sanding is a key technological measure for sanding prevention. The Bohai Oilfield currently utilizes static methods for sanding prediction, which do not account for changes in ground stress, water saturation, reservoir pressure depletion, and pressure drawdown during oil production processes, and these have dynamic effects on reservoir sanding. This results in significant difference between the sanding predictions of the methods used and reality, and these predictions only provide general guidance for sanding prevention design. In this work, we investigated commonly used well completion methods in the Bohai Oilfield, namely oriented perforating and horizontal open hole wells, and constructed a method for predicting dynamic sanding throughout the lifecycle of an unconsolidated sandstone reservoir in the Bohai Oilfield based on analyses of the factors and mechanisms governing dynamic sanding and mechanical stabilities of wellbores. Our method provides a comprehensive analysis of the dynamic effects of ground stress, water content, pressure drawdown, and pressure depletion on reservoir sanding, thus enabling dynamic predictions and analyses of sanding risks throughout the petroleum extraction lifecycle of a reservoir. In practice, it was shown that our proposed method predicted the sanding of unconsolidated sandstone reservoirs in a more precise, accurate, and realistic manner than existing methods. The findings of this study will therefore contribute to optimization of sanding prevention measures, thus reducing costs and improving productivity.

Key words: sanding risk, dynamic prediction, full lifecycle, sanding prevention, unconsolidated sandstone, Bohai Oilfield