井涌余量对套管下入深度的影响研究

Study on Effect of Kick Tolerance on Casing Setting Depth

套管下入深度设计在井身结构设计中十分重要,直接影响一口井的套管层次和作业安全。在进行套管下入深度设计时,必须考虑井涌余量的影响。目前关于井涌余量的确定尚缺乏统一的标准,给套管下入深度的设计带来一定影响。鉴于此,根据井控作业程序,给出了关井和循环排出溢流2个关键阶段的井涌余量计算方法,进而得出了2种套管下入深度设计方法,即关井法和循环法。通过算例仿真分析,对比了关井法和循环法对套管下入深度设计的影响。分析结果表明:关井法计算结果偏于保守,单层套管下入深度较小,安全性较高;循环法可以有效增加单层套管下入深度,减少套管层次,比较经济。最后,对应用循环法设计套管下入深度的影响因素及其适用性进行了分析。研究结果可为合理地进行套管下入深度设计提供理论参考。

The design of the casing setting depth is very important in casing program design,which directly affects the casing program and operation safety of a well.The kick tolerance is a must consideration in the design of casing setting depth.At present,the lack of uniform standards for the determination of kick tolerance still brings an uncertainty on the design of the casing setting depth.In view of this,according to the well control operation procedure,the calculation methods of the kick tolerance in the two key phases of shut-in and circulation are given.And two types of casing setting depth design methods are obtained-the shut-in method and circulation method.Through simulation analysis,the effect of the shut-in method and the circulation method on the casing setting depth is compared.The analysis results show that the shut-in method is more conservative,and results in shallower the singlelayer casing setting depth and higher safety.The circulation method can effectively increase the single-layer casing setting depth,reduce the casing layers,and is relatively economical.Finally,the influence factors and applicability of the circulation method are analyzed.The research results can provide theoretical references for reasonable casing setting depth design.