套管柱在高压工艺条件下的受力及保护浅析

分析了套管柱在高压工艺条件下的受力状况，并给出了计算公式。实施压裂、酸化或注水而形成的高压差和高温差，会使井口处套管和水泥面处套管的受力发生突变。在采用环室或光油管压裂、酸化或注水时，套管处于直接承压状态，其中井口处套管受压力效应、温度效应和重力的综合影响；水泥面处套管则受到附加轴向载荷的作用。通过实际井例进行了计算和验证。在此基础上，提出了采用封隔器管柱保护套管的途径。此外，还对封隔器管柱作了受力分析。

Forces on Casing String under High-Pressure Working Conditions

The authors analyze the forces on the casing string under high-pressure working conditions, and give relevant equations for calculation. The high pressure difference and high temperature difference formed in fracturing, acidizing and water injecting will cause sudden variation of the forces on the casing at the wellhead and around the cement surface. The casing at the wellhead is effected comprehensively by pressure,temperature and weight, while the casing around the cement surface is acted by the additional axial load. In the light of this situation, the authors recommend adopting the packer string to protect the casing and make an analysis of the forces on the packer string.