弹性膨胀型桥堵增效材料的研究及其应用OA

Current bridging lost circulation materials(LCMs)exhibit poor lost circulation control performance and limited pressure bearing capacity when used in controlling mud losses into complex fractured formations such as those with multiscale fractures and stress-sensitive fractures,and mud losses controlled with these LCMs are easy to re-occur.Based on the idea of enhancing the elasticity and toughness as well as the volumetric expandability of the LCMs,an elastic expanding bridging efficiency-enhancing material was developed.The optimal synthesis formula and conditions were obtained through component optimization experiments.Laboratory evaluations were conducted on the material mechanics,expansion performance and lost circulation control capacity of the elastic expanding bridging efficiency-enhancing material,followed by field application.The research findings show that the elastic expanding bridging efficiency-enhancing material exhibits high compressive strength and good elasticity-toughness before and after expansion.After aging at 160℃,the volume of the elastic expanding bridging efficiency-enhancing material can expand to 116.67%of its original volume.Through elastic-tough deformation and continuous three-dimensional expansion,the elastic expanding bridging efficiency-enhancing material can enhance the compactness of the plugging layers and improve their elasticity-toughness,thereby strengthening the pressure-bearing and anti-breathing capacity of the seal.Preliminary field applications of this elastic expanding bridging efficiency-enhancing material in wells with lost circulation in the southwest drilling block have achieved favorable results in mud loss control,demonstrating broad promotion prospects.