川西二叠系超深风险井永胜1井钻井关键技术

Key drilling technology of Permian ultra-deep risk exploration well YS1 in western Sichuan

针对川西二叠系超深风险井永胜1井在钻探中存在地质条件异常复杂、上部陆相地层软硬交错、易发生井斜超标、可钻性差,海相地层高温高压、含硫化氢等难题,优化必封点位置,设计井身结构为四开备五开;配套采用复合钻井、垂直钻井等提速工艺;优选高效钻头,优化深部井段钻井液体系和性能。实钻结果表明,永胜1井钻井工程设计科学合理,全井钻井周期356.45 d,平均机械钻速2.39 m/h,创川西地区钻达6 000 m井深的最快纪录。该井顺利完钻也为川西地区7 000 m超深井钻井积累了宝贵经验。

Since the ultra-deep well YS1 in western Sichuan has several drilling difficulties such as complex geological conditions, soft and hard staggered upper continental strata, poor drillability, high temperature and high pressure of marine stratum, hydrogen sulfide gas, etc., the designers optimized the setting position, recommended the four casing scheme and reserved five casing scheme;compound drilling and vertical drilling and other techniques were selected to increase drilling speed;high-efficiency drill bits were optimized, and the drilling fluid system and performance were improved in deep well sections. The drilling engineering design and technique plan were adapted scientifically which lead to an average penetration rate 2.39 m/h and the average drilling operation time 356.45 d, creating the shortest record of drilling to 6,000 m depth in western Sichuan. The successfully completed well provides important references for 7,000 m ultra-deep wells in the same area.