新和地1井复杂地层水泥封孔护壁造斜技术

Cement plugging and sidetracking in complex formation at well Xinhedi1

摘要:

新和地1井在钻进1314.00～1419.98 m孔段时钻遇巨厚破碎带，地层高度破碎、大倾角、富含水系，孔壁掉块、水敏坍塌现象严重。钻进时孔内阻力大，钻具放不到底，孔内事故多发，破碎带难以钻穿。为处理孔内事故并钻穿巨厚破碎带，采用水泥封孔护壁造斜技术。受孔内复杂因素影响，特别是1358.76～1396.46 m破碎带内水系对水泥浆的稀释和冲蚀破坏作用，前期多次水泥封孔失败，浪费了大量物资及工期。现场通过试验，总结出了一套有针对性的、实用的技术方案，解决了现场的水泥封孔技术难题，提高了水泥封孔护壁造斜的成功率。新和地1井深孔复杂地层水泥封孔护壁造斜技术对今后施工类似工程具有一定的参考意义。

Abstract:

A broken section of great thickness was encountered in well Xinhedi1 during drilling from 1314.00m to 1419.98m. The formation was highly broken with a large dip angle, and rich in aquifers. Falling stones and water sensitive collapse of the borehole wall were much serious. During the drilling operation, the drilling tools cannot be lowered into the borehole bottom due to the large resistance in the hole. Borehole incidents occurred frequently, and it was difficult to drill through the broken section. In order to deal with the borehole incident and to drill through the broken formation, cement plugging and side tracking were adopted in these zones. Influenced by the complex factors of the hole, especially the dilution of the drilling mud and the erosion resulted by the water systems in the broken belt from 1358.76m to 1396.46m, cement plugging failed early for many times, which wasted a lot of materials and the drilling time. A set of specific and practical measures were developed through field testing, which solved the technical difficulties of the cement plugging in the field, and improved the success rate of the wall protection with cement plugging and side tracking, providing reference for similar construction in the future.