关键词: 储层损害, 钻井液, 侵入深度, 预测模型, 暂堵技术

Abstract:

The invasion of solids and filtrate in drilling fluids is the key reason to cause damage of high-permeability sandstone reservoir. A model for defining the invasion radius of solids and filtrate in drilling fluids under the dynamic condition was built up, according to the mass conservation equation and radial friction losses equation.In order to confirm some parameters in the model, the experiences of filtration API and dynamic fluid loss were tested in laboratory, and the results from the API filter test and dynamic fluid loss test were applied to the model. The prediction results indicated that the invasion radius of solids became great when the core permeability increased.The ideal filling temporary plugging technique could reduce the invasion radius of solids in drilling fluids.The pressure difference,filtrate viscosity,permeability and thickness of external and internal mud cakes could affect the filtration invasion radius.

Key words: reservoir damage, drilling fluid, invasion radius, prediction model, temporary plugging technique