Fault fractures usually have large openings and considerable extension. Accordingly, cross-linked gel materials aregenerally considered more suitable plugging agents than water-based gels because the latter often unde...Fault fractures usually have large openings and considerable extension. Accordingly, cross-linked gel materials aregenerally considered more suitable plugging agents than water-based gels because the latter often undergo contaminationvia formation water, which prevents them from being effective over long times. Hence, in this study, aset of oil-based composite gels based on waste grease and epoxy resin has been developed. These materials havebeen observed to possess high compressive strength and resistance to the aforementioned contamination, therebyleading to notable increase in plugging success rate. The compressive strength, thickening time, and resistance toformation water pollution of these gels have been evaluated indoors. The results show that the compressivestrength of the gel can reach 11 MPa;additionally, the related gelation time can be controlled to be more than3 h, thereby providing a safe construction time;Invasion of formation water has a small effect on the gel strengthand does not shorten the thickening time. All considered performance indicators of the oil-based gel confirm itssuitability as a plugging agent for fault fractures.展开更多
Carbon/aluminium(C/Al)composites have the advantages of low density and high electrical conductivity,which have potential applications in aerospace,rail transportation and other fields.However,the unstable bonding of ...Carbon/aluminium(C/Al)composites have the advantages of low density and high electrical conductivity,which have potential applications in aerospace,rail transportation and other fields.However,the unstable bonding of the C/Al interface and significant thermal expansion differences have resulted in risks of the composites'failure once suffering from severe thermal shock.In this work,the C/Al composites were prepared by the pressure impregnation method,and silicon(Si)was added to overcome the problems of C/Al non-wettability and thermal expansion differences.The effects of mass fractions of doped silicon on the mechanical properties,electrical conductivity and thermal shock resistance of C/Al composites were also examined.Results show that the formed SiC interlayer has effectively enhanced the interfacial bonding and reduced the differences in the thermal expansion coefficient of each component.As a result,the thermal shock resistance of the composites has been remarkably improved,and the flexural strength could remain 90%of the original level after the thermal shock test,compared with 50%of that without Si doping.展开更多
基金“Research and Application of Key Techniques for Drilling and Completion of Bozhong 19-6 Condensate Gas Field Development-Phase I”sub topic 4“Research on Leakage Prevention and Plugging Techniques for Fault and Buried Hill Reservoirs”,a Project of China National Offshore Oil (China)Co.,Ltd. (Project No.YXKY-2020-TJ-03).
文摘Fault fractures usually have large openings and considerable extension. Accordingly, cross-linked gel materials aregenerally considered more suitable plugging agents than water-based gels because the latter often undergo contaminationvia formation water, which prevents them from being effective over long times. Hence, in this study, aset of oil-based composite gels based on waste grease and epoxy resin has been developed. These materials havebeen observed to possess high compressive strength and resistance to the aforementioned contamination, therebyleading to notable increase in plugging success rate. The compressive strength, thickening time, and resistance toformation water pollution of these gels have been evaluated indoors. The results show that the compressivestrength of the gel can reach 11 MPa;additionally, the related gelation time can be controlled to be more than3 h, thereby providing a safe construction time;Invasion of formation water has a small effect on the gel strengthand does not shorten the thickening time. All considered performance indicators of the oil-based gel confirm itssuitability as a plugging agent for fault fractures.
基金National Natural Science Foundation of China,Grant/Award Numbers:52077182,51837009,U19A20105Fundamental Research Funds for the Central Universities,Grant/Award Number:2682018CX17+1 种基金National Rail Transit Electrification and Automation Engineering Technology Research ProjectChengdu Guojia Electrical Engineering Co.Ltd,Grant/Award Number:NEEC-2018-B06。
文摘Carbon/aluminium(C/Al)composites have the advantages of low density and high electrical conductivity,which have potential applications in aerospace,rail transportation and other fields.However,the unstable bonding of the C/Al interface and significant thermal expansion differences have resulted in risks of the composites'failure once suffering from severe thermal shock.In this work,the C/Al composites were prepared by the pressure impregnation method,and silicon(Si)was added to overcome the problems of C/Al non-wettability and thermal expansion differences.The effects of mass fractions of doped silicon on the mechanical properties,electrical conductivity and thermal shock resistance of C/Al composites were also examined.Results show that the formed SiC interlayer has effectively enhanced the interfacial bonding and reduced the differences in the thermal expansion coefficient of each component.As a result,the thermal shock resistance of the composites has been remarkably improved,and the flexural strength could remain 90%of the original level after the thermal shock test,compared with 50%of that without Si doping.
