摘要
为提高现有导向钻具组合井眼轨迹控制能力,针对近钻头变径稳定器导向钻具造斜特性开展了研究。根据纵横弯曲梁法和三弯矩方程,考虑钻具结构弯角和变刚度管柱的影响,建立了带近钻头可变径稳定器的导向钻具组合力学特性分析模型,采用单因素法,对各种条件下近钻头可变径稳定器外径对钻具造斜能力的影响进行分析。分析结果表明,近钻头可变径稳定器外径对钻具造斜能力影响显著,在所研究的参数范围内,钻具长度和井径扩大率对复合钻进造斜率的影响较为明显,上稳定器和钻压的影响次之,螺杆钻具结构弯角对复合钻进造斜率的影响最小。最后根据研究结果并结合现场实际工况,设计并研制出了井下遥控式近钻头可变径稳定器导向钻具。
To improve the well path control capability of existing steerable assembly, a study is conducted on deflecting characteristic of steerable assembly with near-bit adjustable diameter stabilizer. Based on the beam col- umn theory and the three-moment equation, a model considering the effect of positive displacement motor bending angle and variable stiffness of drillstring is established for the mechanic analysis of the assembly. The effects of sta- bilizer＇ s outer diameter on the assemblyg deflecting results under variable conditions are analyzed by using the sin- gle-factor method. The result of investigation shows that the outer diameter has a significant effect on the deflecting results. Among the parameters studied, the assembly length and the hole enlargement rate have the greatest effects on the build-up rate, followed by the upper stabilizer and the WOB, while the positive displacement motor bending angle has the least effects. Combining the results and the field conditions, a remote downhole steerable assembly with near-bit adjustable diameter stabilizer is designed and developed.
出处
《石油机械》
北大核心
2014年第5期39-43,共5页
China Petroleum Machinery
关键词
近钻头
变径稳定器
导向钻具
造斜
复合钻进
near-bit
adjustable diameter stabilizer
steerable assembly
deflecting
compound drilling
