下部小尺寸管柱冲砂工艺及工具研制

Development of Sand Washing Process and Tools for Lower Small Size Pipe String

海上油田生产井的上部采用244.5mm(9英寸)生产套管,下部采用177.8mm(7英寸)尾管完井。防砂管柱内径小,下入更小内径的冲砂管柱,正循环冲砂,上部环空面积大,冲砂液上返速度小,携砂能力弱,且地面循环设备压力大;反循环冲砂,冲刺力小,效率低。针对现场作业需求,提出下部小尺寸管柱冲砂工艺技术,研发分流封隔器、双层管柱等关键工具,实现上部反循环,下部正循环冲砂作业,提高冲砂时效,并降低地面循环设备功耗。

The offshore production wells are applying 9 5/8"production casing at the top and 7"tailpipe at the bottom.The inner diameter of sand preventing pipe column is small while the inner diameter of sand washing pipe column is smaller.During the forward cycling sand washing,the upper ring area is large and the return speed of the punching fluid is slow,which causes the weakness of sand carrying and high pressure of the ground recycling equipment.During the reverse cycling sand punching,the impulse force is small with lower efficiency.According to the requirement of field operation,the technology of sand washing with lower small size pipe column and the key tools such as shunt packer,double layer pipe column have been discussed and developed.The upper reverse cycling and the lower forward cycling sanding washing operation have been achieved,while shorter sand washing time consuming and the smaller power consumption of the ground circulation equipment have been realized.