采用磨料水射流喷丸(Abrasive Water Jet Peening,AWJP)与超声表面滚压(UItrasonic Surface Rolling Process,USRP)高能复合改性工艺对40CrNiMoA钢进行了表面改性处理。探明了经高能复合改性处理后材料的表面性能参数影响规律。结果表明...采用磨料水射流喷丸(Abrasive Water Jet Peening,AWJP)与超声表面滚压(UItrasonic Surface Rolling Process,USRP)高能复合改性工艺对40CrNiMoA钢进行了表面改性处理。探明了经高能复合改性处理后材料的表面性能参数影响规律。结果表明,高能复合改性试样表面硬度为632 HV,比未改性试样增加了31%。最大残余压应力(Compressive Residual Stress,CRS)约为1100 MPa,分布在距离最表面约45μm位置处,CRS场有效深度超过了600μm。同时,表面粗糙度度显著降低,表面质量明显改善。高能复合改性获得了理想的表面性能参数。展开更多
To visually describe the sanding pattern,this study constructs a new particle-scale microstructure model of weakly consolidated formation,and develop the corresponding methodology to simulate the sanding process and p...To visually describe the sanding pattern,this study constructs a new particle-scale microstructure model of weakly consolidated formation,and develop the corresponding methodology to simulate the sanding process and predict sand cavity shape.The microstructure model is a particle-objective model,which focuses on the random sedimentation of every sand grain.In the microstructure,every particle has its own size,sphericity and inclination angle.It is used to simulate the actual structure of cemented granular materials,which considers the heterogeneity and randomness of reservoir properties,provides the initial status for subsequent sanding simulation.With the particle detachment criteria,the microscopic simulation of sanding can be visually implemented to investigate the pattern and cavity shapes caused by sand production.The results indicate that sanding always starts initially from the borehole border,and then extends along the weakly consolidated plane,showing obvious characteristic of randomness.Three typical microscopic sanding patterns,concerning pore liquefaction,pseudo wormhole and continuous collapse,are proposed to illustrate the sanding mechanism in weakly consolidated reservoirs.The nonuniformity of sanding performance depends on the heterogeneous distribution of reservoir properties,such as rock strength and particle size.Finally,the three sanding patterns are verified by visually experimental work.The proposed integrated methodology is capable of predicting and describing the sanding cavity shape of an oil well after long-term sanding production,and providing the focus objective of future sand control measure.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant No.51774307,52074331,42002182)partially supported by Major Special Projects of CNPC,China(ZD2019-184)。
文摘To visually describe the sanding pattern,this study constructs a new particle-scale microstructure model of weakly consolidated formation,and develop the corresponding methodology to simulate the sanding process and predict sand cavity shape.The microstructure model is a particle-objective model,which focuses on the random sedimentation of every sand grain.In the microstructure,every particle has its own size,sphericity and inclination angle.It is used to simulate the actual structure of cemented granular materials,which considers the heterogeneity and randomness of reservoir properties,provides the initial status for subsequent sanding simulation.With the particle detachment criteria,the microscopic simulation of sanding can be visually implemented to investigate the pattern and cavity shapes caused by sand production.The results indicate that sanding always starts initially from the borehole border,and then extends along the weakly consolidated plane,showing obvious characteristic of randomness.Three typical microscopic sanding patterns,concerning pore liquefaction,pseudo wormhole and continuous collapse,are proposed to illustrate the sanding mechanism in weakly consolidated reservoirs.The nonuniformity of sanding performance depends on the heterogeneous distribution of reservoir properties,such as rock strength and particle size.Finally,the three sanding patterns are verified by visually experimental work.The proposed integrated methodology is capable of predicting and describing the sanding cavity shape of an oil well after long-term sanding production,and providing the focus objective of future sand control measure.
