Research On The Dynamic Response Of The Oil Well Perforating String To Explosive Impact Load

Perforating operations is a necessary part of the exploitation of oil and gas wells, inorder to improve the oil production efficiency, the power of perforating guns become stronger,the high impact overload is also increase during perforation, high shock loads have becomemajor factor for string and wellbore instability, bend, break and cause wells accident.Damage and buckling response pattern to explode string impact under the perforations inthe perforated shells has become one of the core issues related to the efficient production ofoil and gas wells.In this paper, perforation output string explode under impact loading effect was studied,obtain the output characteristics and loading rule of the blast loading in the perforatedsection in different perforating conditions, by means of simulation experiments anddynamics. and studied the dynamic response of the column. Specific research work is asfollows:(1) Against the perforations string unique structure and working principle, madecorresponding theoretical analysis by detonation Physics and stress wave theory, get thedetonation wave propagation in a string of perforated interval and the Damage form of thecolumn.(2) Design and create dynamic storage test system of high-impact overload test suitablefor high temperature and pressure, use the system for perforation perforating string sectiondynamic loads test in different conditions. Gain the dynamic acceleration data in axial,radial and circumferential directions.(3) Established numerical model of perforating string section in the explosion shockeffect, the perforation of127perforating gun were calculated by finite element analysissimulation software Ls-dyna at60degrees, got the dynamic response of the gun bodiesstructure. use of static analysis software workbench analyzes the oil column dynamic loadand deformation characteristics in different loads forms.(4)Systematic analysis of the127and89perforating gun barrel axial, radial andcircumferential acceleration rule changes and the change of barrel speed and displacementin different phases perforation and different charge volume condition. I also analyzed thepressure changes in the outer perforating string section. Through this study work, which can Provides a new means and method to analyze thedynamic response of explosive loading under perforations string by use experimental andnumerical methods, initially revealed perforation string load output laws of explosion, Theprovides an important support for further research to improve the perforating process,improve the efficiency of perforation and perforation reduce accidents.