中国石油网消息：今年以来，青海油田聚焦气田开发中后期复杂井况治理，接连攻克极端腐蚀管柱打捞、双层套管开窗两大技术瓶颈，截至4月17日，已形成5项成熟井下作业新工艺，为高原气田大修井处置、老井产能恢复筑牢技术根基。

China Oil News: Since the beginning of this year, Qinghai Oilfield has focused on addressing the complex well conditions during the mid-to-late stage of gas field development. It has successively overcome two major technical bottlenecks: extreme corrosion pipe string retrieva l and double-layer casing window opening. As of April 17th, five mature downhole operation new techniques have been formed, laying a solid technical foundation for the major repair of gas fields in the plateau area and the recovery of production capacity of old wells.

当前，青海油田各气田生产时间较长，出水、出砂、介质腐蚀引发管柱变形、断脱卡阻、套管损坏等问题频发，叠加双层套管开窗、窄间隙作业等新挑战，常规大修工艺难以适配，严重制约气田开发效益。对此，青海油田成立油气水井大修项目组，依托油气工艺研究院以技术创新破解作业瓶颈，加快构建适配高原特点的井下作业技术体系。

Currently, the various gas fields in Qinghai Oilfield have been in production for a long time. Problems such as water and sand production, medium corrosion, causing pipe column deformation, disconnection and clogging, and damage to the casing occur frequently. Coupled with new challenges such as double-layer casing windowing and narrow gap operations, the conventional major repair techniques are difficult to adapt to, seriously restricting the development efficiency of the gas fields. In response to this, Qinghai Oilfield has established an oil and gas well major repair project team, relying on the Oil and Gas Technology Research Institute to solve the operational bottlenecks through technological innovation, and accelerate the construction of an underground operation technology system suitable for the characteristics of the plateau.

台南气田台2-1井为典型治理案例。该井已服役14年，因油管长期严重腐蚀断脱被迫停产，油管壁厚仅剩1—1.5毫米，管体被挤压成扁平的“一字”形态，最大宽度达102至110毫米，油管结构强度近乎失效。同时，井内还存在套管开窗、仪器落井、套管变形等多重复杂工况，大修打捞难度行业罕见。

The No. 2-1 well in the Tainan gas field is a typical case of remediation. This well has been in service for 14 years. Due to severe corrosion and breakage of the tubing over a long period, it was forced to be shut down. The wall thickness of the tubing was only 1-1.5 millimeters, and the pipe body was compressed into a flat "straight line" shape, with the maximum width reaching 102 to 110 millimeters. The structural strength of the tubing was nearly compromised. At the same time, there were multiple complex working conditions inside the well, such as casing windowing, instrument falling into the well, and casing deformation. The difficulty of major repair and salvage was extremely rare in the industry.

针对此极端难题，油田井下作业工艺研究团队创新采用“低钻压+大通径+反循环”复合打捞工艺，严格将钻压控制在1吨以内，配套定制专用打捞工具。经过17天连续奋战、59趟精细作业，累计处理变形腐蚀管柱176米，作业效率从初期1.26米/趟大幅提升至10.1米/趟，成功疏通井筒、恢复气井产能，攻克多项复杂工况下大修打捞技术瓶颈。

To address this extremely difficult problem, the research team specializing in oilfield downhole operation techniques innovatively adopted a "low drilling pressure + large diameter + reverse circulation" composite retrieva l method. They strictly controlled the drilling pressure within 1 ton and customized special retrieva l tools. After 17 consecutive days of hard work and 59 meticulous operations, a total of 176 meters of deformed and corroded pipe columns were processed. The operation efficiency significantly increased from the initial 1.26 meters per operation to 10.1 meters per operation. The wellbore was successfully unclogged and the gas well's production capacity was restored. They successfully overcame multiple technical bottlenecks in large-scale repair and retrieva l under complex working conditions.

“这项复合打捞工艺的成功应用，破解了极端腐蚀管柱常规打捞失效难题！”油田油气工艺研究院井下作业工艺研究所所长赵铭辉说道，该工艺形成了高腐蚀、多出砂气田大修打捞技术模板，为同类井处置提供了成熟方案。

"The successful application of this composite salvage technology has solved the problem of failure in conventional salvage of extremely corroded pipe columns!" said Zhao Minghui, the director of the Downhole Operation Technology Research Institute of the Oilfield Oil and Gas Technology Research Institute. This technology has formed a template for salvage operations in high-corrosion and multi-sand gas field well rework, providing a mature solution for similar well treatments.

与此同时，涩3-127井双层套管开窗作业也取得关键突破，填补了疏松砂岩气藏套损治理工艺空白。该井需完成气层套管与技术套管双层开窗。面对高强度钢级、52.4毫米窄间隙、无成熟经验可借鉴等难题，团队通过柔性钻具革新、开窗点精准选型、专用工具升级、分级参数控制四项创新，历经7次试验顺利完成开窗与裸眼钻进，打破了涩北气田仅能进行单层套管开窗的局限。

Meanwhile, the double-layer casing window operation at Well 3-127 also achieved a key breakthrough, filling the gap in the wellbore casing damage treatment technology for loose sandstone gas reservoirs. This well required completing the double-layer windowing of the gas layer casing and the technical casing. Facing difficulties such as high-strength steel grades, a 52.4-millimeter narrow gap, and the lack of mature experience to draw upon, the team innovated through four measures: flexible drilling tools, precise selection of windowing points, upgrading of specialized tools, and hierarchical parameter control. After 7 trials, they successfully completed the windowing and achieved open-hole drilling, breaking the limitation that only single-layer casing windowing was possible in the Shibi North gas field.

目前，青海油田已形成复合打捞、双层套管开窗、套磨铣优化等核心技术，构建起覆盖大修井治理、老井侧钻、产能恢复的全链条工艺体系。年初以来，5项新工艺加快推广应用，作业效率提升5个百分点以上，施工安全性显著提高，成功恢复多口故障井产能，为气田长期稳产、高质量发展提供坚实技术保障。

At present, Qinghai Oilfield has developed core technologies such as composite fishing, double-layer casing window opening, and optimization of casing milling and grinding. A complete chain process system covering major well repair, old well sidetracking, and capacity restoration has been established. Since the beginning of the year, five new technologies have been accelerated for application and promotion. The operation efficiency has increased by more than 5 percentage points, the construction safety has been significantly improved, and the production capacity of multiple faulty wells has been successfully restored, providing solid technical support for the long-term stable production and high-quality development of the gas field.