Casing Bearing Capacity with Shear Load for Shale Gas Wells

Casing radial deformation during complex fracturing process was seriously for shale gas wells in Sichuan district of China, with an average casing deformation rate of 50%. The bridge plug, perforating gun and other tools can’t successfully pass with deformed casing. Aiming at the 3-D logging morphology for deformed casing of shale gas wells, the failure modes and mechanisms were analyzed by using elasticity and theoretical mechanics. Many factors should be evaluated and integrated to achieve quantitative evaluation model including geology feature, wellbore trajectory, cement property, casing material and hydrofracture process. Meanwhile, with the aid of the self-developed unconventional oil and gas well casing simulation test equipment, the casing bearing capacity with shear load were carried out, established the relationship between shear load value and radial deformation, constructed the casing failure criterion with shear force, which provides technical support for casing design and selection in shale gas wells.