Analysis and Calculation of the Forces Exerting on Casing in the Process of Running into High Angle Deviated Hole

A mechanical model of the casing in 3D borehole was established. In it were considered the influences of deviation angle, the density and pressure differences of the liquids inside and outside casing and the geometric and physical parameters of casing. By solving the mechanical model, the casing bearing forces can be obtained under the conditions of different hole types, mud density, casing suspension length and casing running ways. The software for solving the model was developed, and it can be used for predicting the frictional force in casing running process and for selecting casing running way. Two examples show that the results predicted by the software are identical with ones really measured.