梅普卡斯油田NAIMAT-1井钻井液技术

Drilling fluid technology in Mapcos oilfield, Pakistan

梅普卡斯油田位于巴基斯坦散得省东南部 ,是OPI石油公司的主力油田。梅普卡斯油田地层情况复杂 ,二开井段有大段泥岩、泥灰岩及石灰岩 ,水敏性强 ,极易水化分散膨胀 ;砂泥岩胶结性差 ,容易发生坍塌 ,钻井过程中常出现缩径、井塌和卡钻等井下复杂事故 ,导致油气井报废。因此 ,采用氯化钾乙二醇聚合物钻井液体系 ,配合相应的工艺技术 ,解决了复杂井段钻井过程中出现的复杂问题。现场应用表明 ,氯化钾乙二醇聚合物钻井液抑制防塌能力强 ,悬浮携岩能力好 ,流变性优良 ,性能稳定 ,适应了该油田地层特点 ;钻井过程中井壁稳定 ,井下安全 ,井径规则 ,有利于提高机械钻速 ,缩短钻井周期 。

Mapcos oilfield, which is located in the southeast of Sindh Province of Pakistan, is a main area of the OPI oil company. Formation conditions of the oilfield is very complex, e.g., thick shale, marl and limestone which are highly water sensitive exist in φ 311 mm hole; shrinking, sloughing and sticking are often take place in unconsolidated sandstone and sometime even make wells useless . Potassium chloride glycol polymer drilling fluid system and corresponding technology were used in the field to solve the complicated problems above. Results showed that the system has strong sloughing control and good suspending abilities, traffic rheology and stable properties which completely adapts the oilfield formation characteristics.By using it, stable borehole and regular hole were obtained and ROP was improved, the drilling period was shorted ,as well as reservoir was protected effectively.