超高密度（ρ≥3.00g／cm^3）钻井液的研究与应用

官3井二叠系阳新统存在压力系数为2．85的超高压地层，需用密度为2．92－3.00g/cm^3的钻井液钻井，通过研究重晶石的表面性质及其他技术指标，在优选出高效稀释剂和润滑剂的基础上，胡定了可配制密度为3．02g/cm^3钻井液的重晶石技术指标,并确定了钻井液中膨润土的最佳加量为10.4-12.5g/L.稀释液为DQG－1碱液，润滑剂为1％－3％的FRH，护胶剂为PSC，经室内试验和在井深400m实钻应用证明，超高密度钻井液流变性，沉降稳定性及其他性能良好，配制及维护处理简易。

Study and application of ultra-high density drilling fluid

Extremely high pressure formation exists in the Permian system of well Guan-3, with the pressure factor as high as 2. 85, and the high density drilling fluid of 2. 92- 3. 0 g/cm3 needs to he used. This paper tries to present a high density drilling fluid system for using in this condition. It investigates and determines the proper barite specifications, and the optimal clay usage as 10. 4- 12. 5 g/cm3; DQG-1 alkali lye is used as diluent, and 1% -3% of FRH as lubricant. FSC is used as colloid protecting agent. Laboratory test and field using in the 1000 m hole shows that the high-density system achieves good rheological properly and settling stability, and it's easy for field maintenance and treatment.