Research On Perforating Damage Under Experimental Situation

This paper presents the study of the three kind of shaped charge's effect on the oil layer by sand target under-balanced perforating experiment and flow test of three kinds of shaped-charge on the basis of API criterion in lab. After doing experiments, we did contrast experiment analysis of sand target. We tested the perforation damage zone by doing NMR, SEM, electric probe and grain size analysis experiments etc .As a result we successfully caught the characteristics of the structure and physical property of the perforation damage zone–the thickness of the compacted zone is 12.0mm~13.0mm,and the compacted zone has more compact contact of the grain and more inter-grain chip, the observed micro-fracture on the quartz crystal, the obviously decreasing number of the good-connected big pore, the decrease of the porosity by 13.06%~21.79% ,the decrease of the permeability by 71.98%~78.10% resulting from most of the pore being filled with stone chip compared with the standard stone sample. We advice to build the model and add the experiment results to the model to analyze and calculate the influence of the channel structure, the thickness and the change degree of permeability of damage zone on the flow, so as to decide the effectiveness of the perforating damage and provide basis. The flow depends on following: permeability decrease in crushed zone, the shapes of perforating tunnel, the thickness of crushed zone. The factors that influence core flow efficiency are flow permeability decrease in crushed zone and the thickness of crushed zone. A experiment method to do research on structure of perforating tunnel and a method to calculate seepage flow in perforating tunnel were concluded, and what influence flow and core flow efficiency were presented. All of them can do preparation for optimum perforating design.