胜科1井φ339．7 mm套管双级固井技术

φ339. 7mm Casing Two-Stage Cementing Technology in Well Shengke-1

胜科1井是中国石化的一口重点科学探索井,为保证后续钻进的安全,要求φ339．7 mm套管下至井深 2 932m,且全井封固。针对该井井眼不规则、封固段长、存在多套压力层系、井下情况复杂等技术难点,选择采用双级固井工艺,应用漂珠低密度水泥浆、低失水微膨胀水泥浆、粉煤灰低密度水泥浆、低失水高分散早强水泥浆,成功解决了漏失与封固段长等技术难题,保证了水泥浆返至地面,为后续钻进和处理井下复杂情况奠定了基础。

The Well Shengke-1, a key scientific exploration well of Sinopec, is required to run φ339.7 mm casing to depth of 2 932 m and cement to the surface for safe follow-up drilling operations. There are many challenges arising from cementing job including irregular wellbore, long cementing interval, multiple formation pressure gradients and complex downhoie environment, etc. Regarding such scenario, such measures as two stage cementing technique, low density cement slurry with drifting pearl, low fluid loss and micro-swelling cement slurry, fine coal powder low density cement slurry, low fluid loss and high dispersive earlier strengthened cement slurry are taken and cementing problems are successfully solved to ensure the cement slurry returned to the surface, which provides the foundation for follow-up drilling operations and downhole troubles shooting.