一种准确确定封隔器坐封位置的方法

在管柱从地面下入井筒过程中。由于地层高温、静水应力、油管自重以及浮力等因素的共同作用，将使管柱在轴向上发生伸缩。准确掌握该轴向变形量对工艺设计和施工有重要意义。对管柱轴向变形的影响因素进行了详细分析，得出了任意深度下的轴向变形计算公式。实例计算表明：在封隔器坐封前，影响管柱轴向变形的因素按主次排列为油管自重、温度效应、浮力和横向效应。而轴向总变形量与深度的平方成正比，从而可以计算出任意管柱长度下的轴向变形量。并由此准确计算出封隔器的坐封位置。

A Method to Determine Accurately a Packer Sealed Sitting Position

In the process of pipe string from the ground into the borehole, due to the co-action of high formation temperature, hydrostatic stress, deadweight of the tubing string, and buoyancy forces, the flex of string will occur on the axial orientation. Accurate mastery of the axial deformation has great significance for the technical design and construction. Factors that affect the axial deformation of the pipe string are analyzed in detail, and formula for calculating the axial deformation at an arbitrary depth is obtained. The examples show that, before the packer sitting sealed, tactors affecting the axial deformation of the string by prioritizing are the pipeline deadweight, temperature effect, buoyancy, and horizontal effect. And the total amount of axial deformation is directly proportional to the square depth. Consequently the axial deformation at arbitrary string length can be calculated. And thus the packer sealed sitting position can be accurately calculated.