Wellbore Stability Research to the Direction Well in the Salt Layer
The creep of salt layer often leads to tight hole and pipe sticking, while the deviation angle has an important impact on creep rate when drilling directional wells in salt layer. This paper firstly built the creep constitutive model according to the creep property of salt layers, and defined the creep parameters by field data and log data; then built geomechanics model and applied FLAC3D software to simulate the creep of salt layer, so the safe mud density window drilling the salt layers smoothly is obtained. at the same time, at last analyzed the effect of the deviation angle to the drilling in the salt layer, The conclusion is that when the overburden pressure is major principal stress, drilling mud density is certain, the creep rate increases with the increasing of the deviation angle, the safe mud density also increased, the high deviation angle directional well in salt layers is much more risky. The conclude makes great contribution to the optimizing deviation angle, designing well track and reducing the drilling troubles when drilling directional wells in the salt layer.
Guangfan Li, Yong Huang and Chaohe Chen
H. M. Wu et al., "Wellbore Stability Research to the Direction Well in the Salt Layer", Advanced Materials Research, Vols. 250-253, pp. 4042-4045, 2011