空气/泡沫钻井技术在伊朗19+2项目中的应用

GWDC伊朗19 2项目所承钻的TABNAK气田和SHANUL气田，其钻井难度是世界闻名的。钻井的主要难点是如何克服大井眼长井段低压裂缝性地层漏失、强水敏性泥页岩坍塌和高压盐水层。构造设计井深一般仅为3500m左右，为了封隔复杂地层，所下入的套管可多达5层，最大井眼直径为914．4mm，最大套管外径为762mm。为了解决钻井中遇到的难题，提高机械钻速，缩短钻井周期，使用了空气／泡沫钻井技术并取得成功，从此，空气／泡沫钻井成为顺利完成该项目钻井任务的重要手段，并在应用中日益成熟。文中介绍空气／泡沫钻井技术在TANBAK气田和SHANUL气田的应用情况。

Application of Air/Foam Drilling Technique in 19 + 2 Project of Iran

Drilling operation in TABNAK and SHAN-UL gas field drilled by S & E Great Wall Drilling Co. of CNPC is very difficult. Its key drilling difficulties are how to overcome low pressure fractured reservoir leakage in long section of large hole, water - sensitive mud shale caving and high pressure salt water bearing reservoir. In the two gas fields, target well depth is about 3500m. In order to isolate complex formation, five different size casing have been run in, the biggest hole diameter is 914. 4mm, and the biggest outside casing diameter is 762mm. To improve penetration speed and shorten drilling cycle, using air/ foam drilling technique has obtained success. The paper presents the application of air/ foam drilling technique in TABNAK and SHANUL gas field.