南海超深水喷射钻井导管入泥深度设计方法

Method of Design of Conductor Setting Depth for Ultra-deepwater Jetting Drilling in South China Sea

导管入泥深度的合理设计是深水喷射钻井作业成功实施的关键。分析导管轴向最大承载工况以及导管承载力随时间的变化。研究土剖面已知或未知情况下导管最小入泥深度设计方法,后者能有效地节省对深层土壤进行实际钻孔取心的作业成本。研究表明,导管入泥深度主要由土壤性质、固井井口载荷以及导管静置时间决定。算例验证了方法的准确性。所研究的方法与结论可为南海深水喷射钻井导管入泥深度设计提供有用参考。

The proper design of conductor setting depth was the key factor for succussful jetting drilling operation in deepwater.The maximum axial conductor bearing capacity and its bearing capacity changing with time were analyzed,the design method of the minimum conductor setting depth under the condition of known and unknown soil profiles was studied.And the method could reduce core-drilling cost of deeper soil drilling effectively.Research shows that the conductor setting depth depends on soil characteristics,weight to be landed and set-up time.Example demonstrates that the method is accurate.The related method and conclusion can provide valuable reference for the design of conductor setting depth in deepwater jetting drilling in South China Sea.