Analysis of Downhole Fault Treatment Technologies in Workover Operations of Old Wells
老井修井施工井下故障处理技术分析

摘要

国内老油田已进入开发中后期，井筒老化问题突出，井下故障频发，传统修井工艺与管理模式难以适配复杂工况， 制约油田稳产增效。本文结合老井现场施工工况，归纳井筒堵塞、管柱卡阻、套管破损、层间窜通四类典型单一故障 及多故障叠加的工况特征，对比三类主流故障诊断技术的适用条件与应用短板。从技术匹配、工艺执行、质量安全管 控、人机配套四个维度，剖析当前老井修井施工存在的突出问题，并针对性优化精细化解堵、低损伤解卡、微创修复、 精准封堵四大专项工艺，同时补充复合故障联合处置方案，搭建全流程施工管控体系。整套技术方案以低损伤、精细 化作业为核心，可有效降低故障复发率、规避井筒二次损伤，可为老井修井标准化施工、现场安全风险防控提供参考 依据。

Abstract

Domestic mature oilfields have entered the middle and late stages of development. Wellbore aging has become increasingly prominent, and downhole faults occur frequently. Traditional workover technologies and management models are no longer fully adaptable to complex operating conditions, restricting stable production and efficiency improvement in oilfields. Based on the field operating conditions of old wells, this paper summarizes the characteristics of four typical single faults, including wellbore blockage, pipe string sticking, casing damage, and interlayer channeling, as well as operating conditions involving multiple superimposed faults. It compares the applicable conditions and application limitations of three mainstream fault diagnosis technologies. From the dimensions of technology matching, process execution, quality and safety control, and human–machine coordination, the paper analyzes the prominent problems existing in current old-well workover operations. Targeted optimizations are proposed for four special technologies: refined blockage removal, low-damage stuck-pipe release, minimally invasive repair, and precise plugging. In addition, a combined treatment scheme for compound faults is supplemented, and a whole-process construction control system is established. With low-damage and refined operation as the core, the complete technical scheme can effectively reduce the recurrence rate of faults and avoid secondary wellbore damage, providing a reference for standardized workover operations of old wells and on-site safety risk control.