Developing a casing design for the extraction of petroleum in Mannar basin, Sri Lanka

Abstract

To develop an economical casing design program for the Mannar Basin which is safe, and risk minimized, knowledge on Pore Pressure Gradient, Fracture Pressure Gradient, Casing Performance Properties and Casing Design Criteria’s are important. Previous studies present the Hottman and Johnson (1965) method and D-exponent method-Eaton (1975) as accurate methods to predict the pore pressure gradient of the Mannar Basin and the Eaton (1969) method as the most accurate method to predict the Fracture Pressure Gradient of the Mannar Basin. The data extracted from the final well reports and pressure reports of the pearl 1 well of the Mannar Basin are analyzed using the above models to accurately predict the Pore and Fracture pressure gradients of the Mannar Basin. A specific casing design program is developed to suit the conditions of the Mannar Basin by selecting the casing setting depths and sizes and calculating the casing performance properties of Burst, Collapse and Tension, concerning the predicted pore pressure and fracture pressure gradients.