Casing Design.docx

Casing Seat Selection Using the data in columns 1 and 2 of Table 2.1, calculate the fracture gradient at the various

depths using this Equation . Assume ν = 0.4. Table 2.1 :

Solution The following steps may be used to complete columns 3-6 of Table 2.2: (1) The required hydrostatic pressure of mud is taken as equal to pore pressure + 200 psi, where 200 psi is the magnitude of overbalance. Any reasonable value of overbalance may be used. (2) Calculate the pore pressure and mud pressure gradients by simply dividing pore pressure and mud pressure by depth to obtain the gradient in psi/ft.