3300m长江天然气管道穿越工程难点及技术创新

3 300m长江天然气管道穿越工程是世界上首次在大口径管道穿越领域内实施如此长距离的管道穿越工程,面临导向孔对接难度大、扩孔扭矩大、钻井液性能要求高及回收处理难度大、回拖阻力大等技术难题。为此,针对性地采用了以下技术措施:①确定合理的钻具组合,研发并应用了新型193.7mm(S-135)高强度钻杆,采用了新型全程导向电缆技术及旋转磁铁对接技术,成功地完成了导向孔施工;②采用新型设计的可抗大扭矩的168.3mm(V-150)钻杆,优化了扩孔器构造,改进了水力参数的选择,成功降低了扩孔扭矩,完成了扩孔施工,同时极大地提高了扩孔效率;③设计专门针对大吨位回拖阻力的特殊地锚,并通过漂管作业、加入高效润滑剂、采用新型玻璃钢防腐技术保护管道外防腐层的技术措施,保证了回拖施工顺利完成;④优选钻井液配方,保证了孔洞的稳定及钻屑的顺利返排;⑤成功应用离心机回收处理钻井液系统,保证了回收钻井液的质量。上述一系列的技术创新,确保了3 300m长江天然气管道穿越工程的顺利完成,同时也创造或刷新年了多项管道穿越世界纪录。

Engineering difficulties and technical innovation in the Jiangyin Yangtze River Crossing Project 3300 m HDD

The Jiangyin Yangtze River Crossing Project sets up a record with the length of horizontal directional drilling (HDD) of 3300 meters in the world. Many technical difficulties have been inevitably encountered in pilot hole docking, reaming torque, property requirement and recovery processing of drilling fluids, and pull back resistance, and so on. In view of this, first at the pilot hole drilling stage, a reasonable drill tool assembly was chosen, and a new type drill pipe 193.7 mm （S 135） with a high strength was applied along with fully guided cable and rotating magnate docking technologies. Then at the reaming stage, a newly designed drill pipe 168.3 mm (V 150) was adopted along with the optimized reamers and the improved hydraulic parameters to successfully reduce the reaming torque and significantly improve the reaming efficiency. And at the pullback stage, a specific ground anchor was designed for such large tonnage pullback strength, high performance anti friction lubricants were carried by the coaxial distribution delivery tube, and glass fiber reinforced plastics were also utilized for the pipeline coating. Finally, the drilling fluid formula was optimally selected to ensure the hole stability and flowback of drilling cuttings, and a centrifugal was used to recycle the drilling mud to ensure the mud performance. The above technical innovation not only ensured the smooth and successful completion of this HDD project, but broke many records in this respect.