High performance hydraulic supports have a high requirement in strength,toughness and welding ability of socket mate- rial.Targeting this problem,we analyzed the properties of the high strength socket material 30Cr06,...High performance hydraulic supports have a high requirement in strength,toughness and welding ability of socket mate- rial.Targeting this problem,we analyzed the properties of the high strength socket material 30Cr06,used in high performance hy- draulic supports both at home and abroad and developed a new kind of high strength cast steel 30Cr06A,by making use of an or- thogonal experiment,which provided the design conditions for its optimal composition.The result shows that the strength and toughness of the newly developed high strength cast steel 30Cr06A is much better than that of 30Cr06.Theoretical calculations,mechanical property tests and hardness distribution tests of welded joints were carried out for a study of the welding ability of the new material,which is proved to be very good.Therefore,this 30Cr06A material has been successfully used in the socket of high performance hydraulic support.展开更多
As Daqing Oilfield is developing oil layer with a big potential, the requirement for the quality of well cementation is higher than ever before. Cement rock is a brittle material containing a great number of microcrac...As Daqing Oilfield is developing oil layer with a big potential, the requirement for the quality of well cementation is higher than ever before. Cement rock is a brittle material containing a great number of microcracks and defects. In order to reduce the damage to cement ring and improve sealed cementing property at the interface, it is necessary to conduct research on the modification of the cement rock available. According to the principle of super mixed composite materials, various fillers are added to the ingredients of cement rock.Dynamic fracture toughness of cement rock will be changed under the influence of filler. In order to study the damage mechanism of the cement circle during perforation and carry out comprehensive experiments on preventing and resisting connection, a kind of comprehensive experiment equipment used to simulate perforation and multi-functional equipment for testing the dynamic properties of the material are designed. Experimental study of the dynamical mechanical performance of original and some improved cement rock and experiment used to simulate the well cementation and perforation are carried out. Standard for dynamical mechanical performance of the cement rock with fine impact resistance and mechanical properties of some improved cement rock are also given.展开更多
In this study,an explicit dynamic constitutive model was established for ultra high toughness cementitious composites(UHTCCs).The model,based on the Holmquist–Johnson–Cook(HJC)model,includes tensile and compressive ...In this study,an explicit dynamic constitutive model was established for ultra high toughness cementitious composites(UHTCCs).The model,based on the Holmquist–Johnson–Cook(HJC)model,includes tensile and compressive damage evolution,hydrostatic pressure,strain rate,and the Lode angle effect.The proposed model was embedded in LS-DYNA software and then comprehensive tests were carried on a hexahedral brick element formulation under uniaxial,biaxial,and triaxial stress states to verify its rationality through comparisons with results determined by the HJC and Karagozian&Case(K&C)models.Finally,the proposed model was used to simulate the damage caused to UHTCC targets subjected to blast by embedded explosive and projectile penetration,and predictions were compared with corresponding experimental results.The results of the numerical simulations showed that our proposed model was more accurate than the HJC model in predicting the size of the crater,penetration depth,and the distribution of cracks inside the target following the blast or high-speed impact loading.展开更多
文摘High performance hydraulic supports have a high requirement in strength,toughness and welding ability of socket mate- rial.Targeting this problem,we analyzed the properties of the high strength socket material 30Cr06,used in high performance hy- draulic supports both at home and abroad and developed a new kind of high strength cast steel 30Cr06A,by making use of an or- thogonal experiment,which provided the design conditions for its optimal composition.The result shows that the strength and toughness of the newly developed high strength cast steel 30Cr06A is much better than that of 30Cr06.Theoretical calculations,mechanical property tests and hardness distribution tests of welded joints were carried out for a study of the welding ability of the new material,which is proved to be very good.Therefore,this 30Cr06A material has been successfully used in the socket of high performance hydraulic support.
基金the Natural Science Foundation of Heilongjiang Province (Grant No. A9856).
文摘As Daqing Oilfield is developing oil layer with a big potential, the requirement for the quality of well cementation is higher than ever before. Cement rock is a brittle material containing a great number of microcracks and defects. In order to reduce the damage to cement ring and improve sealed cementing property at the interface, it is necessary to conduct research on the modification of the cement rock available. According to the principle of super mixed composite materials, various fillers are added to the ingredients of cement rock.Dynamic fracture toughness of cement rock will be changed under the influence of filler. In order to study the damage mechanism of the cement circle during perforation and carry out comprehensive experiments on preventing and resisting connection, a kind of comprehensive experiment equipment used to simulate perforation and multi-functional equipment for testing the dynamic properties of the material are designed. Experimental study of the dynamical mechanical performance of original and some improved cement rock and experiment used to simulate the well cementation and perforation are carried out. Standard for dynamical mechanical performance of the cement rock with fine impact resistance and mechanical properties of some improved cement rock are also given.
基金Project supported by the National Natural Science Foundation of China(Nos.51678522 , 51878601)。
文摘In this study,an explicit dynamic constitutive model was established for ultra high toughness cementitious composites(UHTCCs).The model,based on the Holmquist–Johnson–Cook(HJC)model,includes tensile and compressive damage evolution,hydrostatic pressure,strain rate,and the Lode angle effect.The proposed model was embedded in LS-DYNA software and then comprehensive tests were carried on a hexahedral brick element formulation under uniaxial,biaxial,and triaxial stress states to verify its rationality through comparisons with results determined by the HJC and Karagozian&Case(K&C)models.Finally,the proposed model was used to simulate the damage caused to UHTCC targets subjected to blast by embedded explosive and projectile penetration,and predictions were compared with corresponding experimental results.The results of the numerical simulations showed that our proposed model was more accurate than the HJC model in predicting the size of the crater,penetration depth,and the distribution of cracks inside the target following the blast or high-speed impact loading.
