Structural Parameter Optimization And Numerical Simulation Analysis Of High Temperature And High Pressure Deep Well Perforator

In high temperature and high pressure deep wells,the perforating gun bears well bore pressure before perforation and the shock wave pressure at the moment of perforation in the process of perforation detonation.Stress concentration is easy to occur in blind hole,which will reduce the integrity and strength safety of perforating gun.Therefore,this paper studied the influence of the structure and depth of blind hole and perforation parameters on the strength of perforating gun.Using ANSYS numerical simulation analysis method,the finite element model is established,the free mesh is divided,the fixed full constraints are applied at both ends,the external pressure is changed,and the influence of blind hole structure and depth on the extrusion strength of perforating gun is analyzed.The results show that when the hole density is 20 holes/m,the aperture diameter is 10 mm,and the phase angle is 90 degrees,the outer blind hole with equal depth is higher than the outer blind hole with unequal depth.When the depth of the blind hole is 3.5-6.5 mm,the extrusion strength decreases gradually with the increase of the depth of the blind hole,which decreases by 31.46%,and when the depth of the blind hole is 5.5-6.5 mm,the degree of decline is the greatest.The influence of perforation parameters on the internal pressure strength of perforating gun is analyzed by changing the internal pressure.The results show that when the hole density is 8-24 holes/m,the internal pressure strength decreases by about 8.84% with the increase of the hole density,and when the hole density is 16-20 holes/m,the decrease is the greatest,about 6.78%.When the hole diameter is 4-18 mm,the internal pressure strength of the perforating gun decreases by about 20.26% with the increase of the hole diameter,and when the hole diameter is 4-6 mm,the decrease is the greatest,with the decrease of 9.26%,the effect is significant;when the phase angle is 30-180 degrees.The internal compressive strength decreases by 4.94% with the increase of phase angle.In this paper,the rule of the influence of the structure and depth of blind hole on the extrusion strength of perforating gun and the rule of the influence of perforating parameters on the internal pressure strength of perforating gun are obtained.The structure optimization design is carried out,and the optimal value and recommended value are given,which can provide a reference for the strength and safety evaluation of perforating gun.