跃满区块是塔里木油田公司近年来重点开发区块。该区块二开裸眼段长达5500 m，钻遇多套地层，安全密度窗口仅为0.01~0.02 g/cm3。现场施工过程中，渗透性漏失与井壁失稳现象严重。采用常规聚磺钻井液施工，钻井液日消耗量高达100 m3，严重制约了聚磺钻井液在该区块的应用。为有效解决这些问题，针对跃满区块不同地层，优选出随钻堵漏剂、超细碳酸钙、纳米封堵剂等封堵材料。通过评价钻井液的高温高压滤失量、高温高压渗透失水、高温高压砂床滤失量、高温高压砂床渗透失水以及正反向岩心驱替等性能，得到针对该区块地质特点的强封堵配方，并在现有跃满3-3井钻井液体系中复配使用。与邻井相比，该井钻井液密度提高0.02~0.04 g/cm3，且未发生明显漏失。该技术的应用，为解决跃满区块渗透性漏失、井壁失稳等技术难题提供了一种新方法。%Yueman Block is a key development target in Tarim Oilfield in the past few years.Although the open-hole second spud-in interval is up to 5 500 m, and the well penetrates multiple layers, the safe density window is only 0.01~0.02 g/cm3. During drilling opera-tion, lost circulation and stability of sidewalls are frequent problems. Using conventional polysulfonate drilling fluid, daily consumption of the drilling fluid may up to 100 m3, which significantly limits the application of polysulfonate drilling fluid in the area. To eliminate these problems, plugging-while-drilling agents, ultra-fine calcium carbonate, nanometer plugging agents and other plugging materials with desirable properties have been used in accordance with specific formation conditions in the Yueman Block. Assessment on HTHP filtration loss, HTHP water loss through filtration, HTHP sand-bed filtration, HTHP sand-bed water loss through filtration and core displacement capacities in both directions provides competent plugging formula suitable for specific geologic conditions in the Block. These drilling fluids have been deployed in combination with existing drilling fluid system in Well Yueman-3-3. Compared with adjacent wells, this well is suitable for the drilling fluid having a density higher by 0.02~0.04 g/cm3, but with no outstanding lost circulation. The innovative technology may provide satisfactory solution to filtration loss, sidewall instability and some other technical problems in the Yueman Block.
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