高压注水对油田套管的损坏及防治分析

Prevention of casing damage caused by high pressure waterflooding.

根据注水开发油田套管的损坏特征 ,分析认为高压注入水窜入泥岩层诱发地应力挤压套管 ,是影响套管变形的主要因素 ;另外 ,当注水压力高于地层破裂压力和上覆岩层压力时 ,会产生单向侧应力剪切破坏套管。为了防止高压注水引起的套管损坏 ,应采取如下预防措施 :注水井适时解堵防膨 ,合理调整注采井网 ,控制压裂垂直裂缝不要延伸至泥岩层 ,提高固井质量及套管强度等。从分析当前套损井治理现状出发 ,提出防治套管损坏总体方针是预防为主 。

The characteristics of casing damage caused by high pressure waterflooding are analyzed. The reasons of casing damage are explained. The measures for prevention of the casing damage are put forward, that is, carrying out timely blocking removal and expansion control of the water injection wells, adjusting rationally the well pattern, preventing the fracturing vertical cracks from extending to the mudstone formation, and improving the cementing quality and the casing strength.