塔里木盆地顺北区块超深井火成岩钻井液技术

针对塔里木盆地顺北区块火成岩地层钻进中存在的井壁失稳严重、恶性漏失风险高、长裸眼漏塌同存、摩阻高和掉块卡钻等钻井技术难点，开展了钻井液体系配方优化研究。根据包被抑制剂对钻井液性能的影响试验、不同降滤失剂作用效果试验、复合封堵剂屏蔽封堵试验和复合润滑剂配比和降摩阻试验结果，研制了强抑制高封堵钾胺基聚磺钻井液。室内试验表明，火成岩岩样在该钻井液中的滚动回收率和线性膨胀率分别为96.07%和1.87%，钻井液能够抗5% NaCl和2% CaSO4污染。该钻井液在顺北1-3井火成岩地层钻进中进行了现场试验，其二叠系火成岩地层平均井径扩大率仅为12.88%，复杂时效比顺北1-1H井缩短了37.9 d；二叠系火成岩井段未发生漏失；辉绿岩地层平均井径扩大率比顺北1井降低了15.7百分点。室内研究与现场试验表明，强抑制高封堵钾胺基聚磺钻井液技术解决了顺北区块超深井火成岩钻井技术难点，可以在该区块进行推广。 

Drilling Fluid Technology for Igneous Rocks in Ultra-Deep Wells in the Shunbei Area,Tarim Basin

Igneous formations in the Shunbei Block of Tarim Basin are characterized by severe instability of bore hole walls, higher risks of severe lost circulation, the coexistence of lost circulation and collapsing in long open-hole intervals, high friction resistances, bit sticking and other technical challenges. Under such circumstances, research has been performed to optimize formulas for drilling fluid systems. With consideration to the results related to coating inhibitors on the performance of drilling fluid, the performance of different filtrate loss agents, shielding effect of compound plugging agents, the ratio of compound lubricant and friction reducing capacities, a potassium amine-based polysulfide drilling fluid system was developed. Lab test results showed that the rolling recovery rate and linear expansion rate of igneous rock samples in the drilling fluid are 96.07% and 1.87%, respectively. The drilling fluid can effectively resist contaminaiton induced by 5% NaCl and 2% CaSO4. The newly developed drilling fluid system has been tested for drilling igneous formations in Well Shunbei1-3. The average enlargement rate of well diameter in Permian igneous rock is only 12.88%, and the drilling time in complex well section was reduced by 37.9 days in comparison with Well Shunbei 1-1H. No loss of circulation occurred in the Permian igneous well interval. The average enlargement rate of the well diameter in the diabase formation decreased by 15.7% compared with that of the Well Shunbei 1.The application of potassium-amine polysulfonated drilling fluid with a high inhibition and sealing performance solved the problems in ultra-deep well and igneous rock formation drilling effectively, it can be deployed extensively in the Block.