压缩式封隔器胶筒变形阶段力学分析

封隔器是常用试采井下工具,胶筒是封隔器中最重要的部件。将压缩式胶筒的变形分为自由变形和约束变形2个阶段,分析了其绝对体积变化规律,得到了使胶筒刚好与井壁接触的轴向力,据此可以确定最小坐封载荷;得到了井壁和中心管对胶筒的约束压力,在此基础上得到了压缩式胶筒的各个应力分量和第四相当应力,据此可以给出坐封力下胶筒的强度,确定合理的坐封力。实例计算解释了现场封隔器胶筒在坐封载荷作用下损坏的原因。

Mechanical Analysis of Compressed Parking during Axial Compressing

The deformation and mechanical properties of compressed packing, the key component in packers, the commonly used and important down hole tools was analyzed. The deformation was divided into two steps, free deforming before the packing contacted borehole and restrained deforming after the packing contacted borehole. The axial force under which the packing is just compressed to contact bore was derived, which could be used to decide the minimum packing force. Also derived were the stresses in compressed packing. So, the reasonable packing force could be determined and the design of compressed packing may be well oriented.