自胶结堵漏技术研究与应用

为了解决裂缝性、缝洞性地层产生的恶性钻井液漏失问题,对这类漏失的堵漏开展了专项研究,形成了自胶结堵漏技术。该技术以胶结剂和膨润土为原料,采用“双液注浆法”的施工工艺,使堵漏浆滞留在漏失通道内,并发生化学反应,形成具有一定强度的固结体。室内研究结果表明,该堵漏浆具有密度低、黏度高的特点,在80℃下24 h抗压强度不超过11 MPa,有利于钻塞,固结时间可通过添加剂调节。针对裂缝性、缝洞性的恶性漏失,现场试验堵漏效果显著,为优质高效地进行钻井施工提供技术保障。 

Study and Application of Self-Cementation Lost Circulation Control Method

A series of studies have been conducted on lost circulation control to deal with severe mud losses into fractures and vugs. A self-cementation lost circulation control method is the product of the studies. This method uses cementation agents and bentonite as the raw materials in the "bi-slurry grouting method", to stay the lost circulation material (LCM) slurries in place in the mud loss channels. Chemical reactions take place in the LCM slurries and set LCMs are formed, plugging the channels. The LCM slurries have low density and high viscosity. The set LCM, after aging for 24 h at 80℃, has compressive strength that is less than 11 MPa, and is easy to drill out. The time required for the LCM slurries to set is controlled by the concentration of an additive. This technology has been applied in field operation, and severe mud losses into fractures and vugs of different sizes were successfully stopped, ensuring high quality and efficient drilling operation.