An experimental programm of investigating the cutting capacity of PDC flat cutters in very hard rock has been performed. Experiments include both the cutting of PDC fixed at different angles on the granite core or bar...An experimental programm of investigating the cutting capacity of PDC flat cutters in very hard rock has been performed. Experiments include both the cutting of PDC fixed at different angles on the granite core or bar and linear cutting with different static thrust on the block of granite. The effects of the rough degree of rock surface, cutting angles, and static thrust on the cutting capacity of PDC in very hard rock were investigated and analyzed. The results show that the single mode of rotary drilling using PDC cutters is not applied for very hard rocks.展开更多
Thermal residual stresses in polycrystalline diamond compact(PDC)cutter arising from the difference in thermal expansion between the polycrystalline diamond(PCD)and the supporting tungsten carbide substrate after sint...Thermal residual stresses in polycrystalline diamond compact(PDC)cutter arising from the difference in thermal expansion between the polycrystalline diamond(PCD)and the supporting tungsten carbide substrate after sintering at high pressure and high temperature were investigated using finite element simulation,laboratory tests and theoretical analysis.The obtained results show that although compressive residual stresses exist both in the interface of PCD table and in the most region of PCD table surface, the tensile residual stress,which is a fatal shortage to PDC,can also occur near the outer diameter area of PCD table,and the maximum value is 690 MPa.Distribution of tensile stress in the PCD table is given through experimental results,which is well consistent with the numerical results.This finding may be significant in designing new PDC cutters with lower residual stress and high cutting behavior.展开更多
基金Project (5 0 1740 5 6)supportedbytheNationalNaturalScienceFoundationofChina project (DE -FG0 3 )supportedbytheNovatekundertheDepartmentofEnergy USA
文摘An experimental programm of investigating the cutting capacity of PDC flat cutters in very hard rock has been performed. Experiments include both the cutting of PDC fixed at different angles on the granite core or bar and linear cutting with different static thrust on the block of granite. The effects of the rough degree of rock surface, cutting angles, and static thrust on the cutting capacity of PDC in very hard rock were investigated and analyzed. The results show that the single mode of rotary drilling using PDC cutters is not applied for very hard rocks.
基金Project(20070533113)supported by the Doctoral Foundation of Ministry of Education of China
文摘Thermal residual stresses in polycrystalline diamond compact(PDC)cutter arising from the difference in thermal expansion between the polycrystalline diamond(PCD)and the supporting tungsten carbide substrate after sintering at high pressure and high temperature were investigated using finite element simulation,laboratory tests and theoretical analysis.The obtained results show that although compressive residual stresses exist both in the interface of PCD table and in the most region of PCD table surface, the tensile residual stress,which is a fatal shortage to PDC,can also occur near the outer diameter area of PCD table,and the maximum value is 690 MPa.Distribution of tensile stress in the PCD table is given through experimental results,which is well consistent with the numerical results.This finding may be significant in designing new PDC cutters with lower residual stress and high cutting behavior.
