新型可视化缝洞恶性漏失评价装置及堵漏体系实验评价

New visualized fracture-cavity type malignant leakage evaluation device and experimental evaluation of plugging system

摘要:

缝洞型地层恶性漏失是最常见且最难以治理的钻井工程复杂情况之一。针对缝洞型恶性漏失室内评价手段缺乏的问题，研制了新型可视化缝洞恶性漏失评价装置，最高实验温度180 ℃，最大缝洞模拟长度60 cm，额定实验压力5 MPa，最大填充堵漏模块直径5 cm，建立了实验评价方法。采用新型可视化缝洞恶性漏失评价装置开展了1 cm和2 cm砾石模拟封堵评价实验，形成了适用于1 cm和2 cm砾石模拟缝洞系统的最优堵漏体系配方；开展了DY9井堵漏体系配方优化现场试验，堵漏承压达5 MPa，堵漏一次成功。研究结果表明，采用新型可视化缝洞恶性漏失评价装置评价封堵层直观可视，便于进行堵漏浆配方优化，堵漏体系中“刚性材料+纤维材料+弹形材料”的合理搭配可形成致密承压封堵，从而实现对缝洞的有效封堵。

Abstract:

Fracture-cavity formation malignant leakage is one of the most common and difficult to control drilling in engineering. To solve the problem of the lack of indoor evaluation means for fracture-cavity type malignant leakage， a new visualized evaluation device for fracture-cavity type malignant leakage was developed. The maximum experimental temperature was 180℃， the maximum simulated length of fracture-cavity was 60cm， the maximum rated experimental pressure was 5MPa， and the maximum diameter of the filling and plugging module was 5cm. The evaluation experiment of 1cm and 2cm gravel simulated plugging was carried out by using the new visualized fracture-cavity type malignant leakage evaluation device， and the optimal plugging system formula suitable for the 1cm and 2cm gravel simulated fracture-cavity system was formed. The formula optimization of DY9 well plugging system was carried out， and the on-site plugging pressure reached 5MPa， and the plugging was successful once. The research shows that the sealing layer can be visually evaluated by the new visualized fracture-cavity malignant leakage evaluation device， which is convenient for the optimization of the plugging slurry formula. The reasonable combination of "rigid material + fiber material + elastic material" in the plugging system can form a dense pressure sealing， so as to realize the effective plugging of the fracture-cavity.