重复射孔对套管强度的影响  

Effect of Repeated Perforation on Casing Strength

作　　者：郑子君 余成[2] 

机构地区：[1]重庆理工大学机械工程学院 [2]重庆交通大学河海学院

出　　处：《石油机械》2017年第12期100-105,共6页China Petroleum Machinery

基　　金：国家自然科学基金青年项目"水岩作用下的裂隙面力学性质;几何形态及水力渗透特征的演变机制研究"(51409028);重庆市教委科学技术研究项目"基于无网格方法的精冲过程数值模拟方法的研究"(KJ1600910)

摘　　要：为避免盲目重复射孔导致的套损和套变,分析了重复射孔对套管抗挤压强度的影响。对射孔套管的挤毁试验进行有限元模拟,重点分析了新、旧2簇射孔相对位置对强度的影响;对射孔作业的冲击效应进行动力学仿真,模拟了冲击应力的传播和套管损伤失效的分布。分析结果表明:重复射孔可明显降低套管的抗挤压能力;新、旧射孔簇分布越均匀,射孔后抗挤压强度越高;重复射孔时,聚能射流造成的冲击应力可能在旧孔附近形成应力集中,造成严重损伤,甚至可导致宏观裂纹的形成。对已射孔套管段进行重复射孔作业,将增加套损和套变的风险,应当综合套管的受力和套损情况,合理制定补射计划。In order to avoid the casing damage and casing deformation caused by unplanned perforation, the effect of repeated perforation on the anti-collapse strength of the casing has been analyzed. The finite element simu-lation of the perforated casing has been carried out to focus on the study of relative position of the new and old per-forations effect on the casing strength. Dynamic simulation of perforation impact has been conducted to simulate the impact stress propagation and casing damage distribution. The results showed that repeated perforation can signifi-cantly reduce the casing anti-collapse strength. The more uniform the distribution of the old and new perforation clusters, the higher the casing anti-collapse strength after perforation. During the repeated perforation, the impact stress caused by the jet may form a stress concentration near the old hole, causing serious casing damage, and even lead to macroscopic cracks. The study showed that repeated perforation at the perforated casing will increase the risk of casing damage and casing deformation. The forces on the casing and casing damage should be comprehen-sively analyzed to formulate the perforation plan.

关 键 词：重复射孔 套管强度 孔间距 有限单元法 冲击应力 

分 类 号：TE925[石油与天然气工程—石油机械设备]