BH-KSM钻井液在冀东油田南堡3号构造的应用

冀东油田南堡3号构造储量大、埋藏深,该地区部署的深井、超深井存在井温高、位移大的特点。通过实验优选出了氯化钾抗高温钻井液体系(BH-KSM)。该钻井液抗温达200℃;具备优良的抑制封堵性和抗CO2污染能力,解决了南堡3号构造深井存在的井壁失稳、高温蠕变、地层流体污染等技术难题,形成了适合该构造深井的配套钻井液技术。现场应用的10口井东营组易垮塌地层井眼扩大率均小于7%,最小的仅为3.98%;现场钻井液流变性能稳定,高温高压滤失量小于12 m L;包被抑制能力强,返出岩屑完整不分散;携砂、携岩能力强,解决了三开大井眼、裸眼段长的井眼净化问题,提高了机械钻速。

Application of BH-KSM Drilling Fluid in Nanpu #3 Structure of Jidong Oilfield

The Nanpu #3 Structure in Jidong Oilfield has big reserves which are deeply buried. Deep and ultra-deep wells have been drilled in this area with high bottom hole temperatures and large horizontal displacements. A high temperature KCl drilling fluid, BH-KSM, was formulated for use in this area. BH-KSM remains stable at temperature up to 200℃, and has excellent inhibitive and sealing capacity, and tolerance to CO2 contamination, essential for dealing with borehole instability, creep of formation at elevated temperatures, and contamination to drilling fluid by formation fluid in Nanpu #3 Structure. Technology for field application of the BH-KSM was engineered for maximum functioning of the mud. Field application of BH-KSM in 10 wells in the Nanpu #3 Structure showed that percent hole enlargement in the Dongying Formation, known for its being water sensitive and prone to collapse, was less than 7%, and the minimum of which being only 3.98%. The mud had stable rheology during drilling. HTHP filter loss can be kept under 12 mL. Cuttings over shale shakers were hard and had good integrity, illustrating good inhibition of the BH-KSM. Good carrying capacity of the mud resulted in satisfactory hole cleaning and increasing rate of penetration.