Wellbore instability

The completion of a well in an unconsolidated sandstone is more complicated than in a consolidated sandstone because of wellbore instability and the need to install solids control. Perforation geometry is an important consideration (3). At low fluid production rates, small quantities of solids may be produced, whereas at high fluid production rates, large quantities of solids may be carried in the production stream. 

Tan, C.P., B.G Richards and S.S. Rahman.(19%b). Managing Physico-Chemical Wellbore Instability in Shales with the Chemical Potential Mechanism. SPE Asia Pacific Oil and Gas Conf, Adelaide, Australia. (1996b). 

Zeynaly-Andabily, E.M., Chen, H., Rahman, S.S. and Tan, C.P. (1996). SPE 36396 Management of wellbore instability in shales by controlling the physical-chemical properties of muds. SPE Asia Pacific Drilling Technology Conf, Kuala Lumpur, Malaysia, pp. 253-261. 

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