Sealing Performance of Packer Element at Worn Casing Section

摘要

In China’s Tarim oil fields, the severe casing wear is found in some ultra-deep wells, and the packer has to set at worn casing section, so the objective evaluation to sealing performance of packer element is urgently needed. For this propose, numerical simulation is carried out on the sealing performance of a modified packer used in filed case. Contact pressure between element and casing with crescent-shaped is calculated by use of commercial ANSYS software. The role of packer components and influences of notch depth, diameter of drill pipe joint, friction coefficient and setting load on contact pressure are discussed in detail. The results show that groove and copper ring of the modified packer play the role of improving contact pressure between element and casing. When packer is set in worn casing section, the minimum contact pressure between packer element and casing occurs at the deepest point of the notch, and key factors that affects contact pressure is the notch depth of worn casing. Improving setting load of packer is an effective way to promote the minimum contact pressure, and reducing friction coefficient between element and casing is also beneficial to promote contact pressure. The influence of diameter pipe joint on contact pressure is less obvious.