Victory Oil Shengtuo Casing Damage Mechanism And Protective Measures

On the basis situation of casing damage and research achievement on casing damage in domestic and abroad, the information of casing damage in ShengTuo Oilfield is introduced. We found that the main style of casing damage is bending and deformation. By the analysis of information on geology, casing history, and also the information of work-over, we made a conclusion that the decline pressure of pay-zone is one of the key important reasons for casing damage in ShengTuo Oilfield. In order to further study the mechanics of casing damage, we founded mechanical mode. On the basis of that, we analyzed the complicated axial load and the effective extrusion load on the casing resulted from the decline pressure of pay-zone formation, and also we got the evaluation method. According to the theory analysis, we can say that the decline pressure of formation really plays an important role in casing damage. So we bring forward some prevention methods, such as re-injection or pressure release of some of the well to make a balance between injection and recovery to postpone the damage rate of casing; improve the quality of drilling, completion and work-over, to improve the resistance capability of casings.