摘要
针对桥塞堵漏材料难以在裂缝内形成稳定的承压堵漏带,承压能力不足而导致堵漏失败的问题,研究了桥塞堵漏材料在裂缝内的堆积状态和封堵类型,提出了笼状结构体封堵裂缝的理论,剖析了笼状结构体的组成,建立了理想的物理模型;研制出了形成笼状结构体的关键材料——SWDJ,并以此为基础,通过实验,得到了能稳定封堵光滑壁面裂缝的堵漏材料配方和堵漏浆液配方。该配方的承压能力大于5.0 MPa,抗温能力大于150℃。分析结果表明:SWDJ在裂缝中主要起包络和增大摩擦的作用——多片SWDJ能将桥塞材料和充填材料缠绕包络在一起,并通过叠加,在裂缝内部形成"堤坝";SWDJ相互叠加后的摩擦系数高达0.76,使各个"基本单元"相互之间的整体性更加稳定,能够承受更大的压力。虽然实际状态下的笼状结构体相对于理想状态下的"笼"具有不完善性,但其基本的作用机理与理论分析相符。
Bridging materials are difficult to form stable plugging zones in the fractures, leading to plugging failures due to a small bearing capacity. In view of this, the accumulation status and plugging types of bridge plugging were studied. Furthermore, a theory of fracture plugging by use of the cage structure was proposed with its composition analyzed, and an ideal physical model was thus built. Moreover, the key material SWDJ of the cage structure was developed. Through experimenting with SWDJ, the formulae were finally worked out for plugging materials and slurry capable of stably plugging smooth wellbore fractures. With these formulae, the wellbore can bear pressures of over 5.0 MPa and resist temperatures of over 150℃. The analysis results show that SWDJ mainly plays the part of enveloping and increasing friction. Multiple pieces of SWDJ can envelope the bridging and filling materials, forming the “dam” in the fractures by means of overlapping; after the overlapping of SWDJ, the friction coefficient reaches up to 0.76, creating a more stable integral structure consisting of each “basic unit”, and allowing the wellbore to bear higher pressures. Although in the actual status, the cage structure is imperfect compared with the “cage” under the ideal condition, its fundamental action mechanism is consistent with the theory.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2013年第10期80-84,共5页
Natural Gas Industry
基金
中国石油海外油气上产2亿吨开发关键技术研究(编号:11.2011E-2505.X.01)资助
