低密度膨胀型堵漏技术在塔深1井的应用

塔深1井设计井深为8000m,在同一裸眼井段中存在多套压力系统,易发生井漏、井涌;而且地层特殊,存在地下水,纵向及横向裂缝交错,大小溶洞直径差别大,非均质性严重,漏失通道存在着进口小、出口大的裂缝形态,增加了堵漏施工难度。采用低密度膨胀型堵漏浆在塔深1井6237~6650m井段进行了堵漏,并分为两段进行。第一段为潜在漏失段(6650~6350m),采用低稠化度堵漏浆。第二段为确定的严重漏失段(6350~6235m),采取中稠化度堵漏浆,其配方为:5m3井浆 25m3井场水 (0.5%~2%)密度调节剂SD-D (2%~3%)低密度油层保护剂SD-A (1%~2%)流型调节剂SD-R (1%~2%)低密度提粘剂SD-V (1%~2%)高效提粘剂SD-HV (1%~2%)填充加固剂MF-1 (5%~6%)填充加固剂MF-2 (60%~80%)悬浮稳定剂SF-1 (1%~2%)棉子皮 (2%~3%)锯末 (3%~4%)云母。该堵漏技术取得了理想的堵漏效果,实现了一次固井。

Low Density Swelling Sealing Technology in Well Tashen-1

Tashen-1 well has a total depth of 8000 m and it is key to examine hydrocarbon in Cambrian. Multiple pressure systems coexist in the same open hole and the lost circulation and the kick are the risks. In this seriously inhomogenous formation, buried water and cross vertical and horizontal fractures exist, the diameter difference between large and small limestone caves is great, and small inlet and large outlet are characteristics of leaking fractures. These challenges are difficult to overcome. The novel low-density swelling sealing system was developed to seal limestones, fractures and voided formation. It was composed of the special chemicals, the chemical sealing agents and the inert sealing materials. The novel sealing technology achieved success in the practice of Tashen-1 well. It can be a foundation to seal high temperature and high pressure fractures and heavily leaking limestone caves hereafter.