Application of low frequency eddy current technology in detecting casing perforation location and evaluating hydraulic-cutting fracture

摘要

Perforation is very an important part in testing oil and perorating in oilfield development.The perforation quality will greatly affect the flow potential of an oil well.If mis-perforation happens,it will cause a great engineering problem.We need to plug the perforating holes then reperforating,which will cause great waste and construction period delay (Hetang Qiao,1992,E103).So perforating hole distribution inspection is very important in oilfield development.Hydraulic cutting fracture is a new technique which can partly substitute conventional perforation,and it is often used in low permeability oil field.Traditional logging such as multi-finger longing can not give correct interpretation when erud fill in the fractures or the fractures are not totally breakthrough.And low-frequency eddy current logging can detect the location of perforation and roughly estimate the perforation effectiveness.In this paper the fundamental principle and application of low-frequency eddy current logging is introduced,which can measure casing perforating hole distribution and newly applied hydraulic-cutting fracture experiments.And the principle and structure of testing sample is also introduced and its application effect is analyzed.