Analysis of Casing Strength in High-Pressure Gravel Packing Based on the Finite Element Method

It used to be held that high-pressure extrusion would severely influnce the strength and duration of casing.Based on 5 inch and 7inch casing,the article intends to conduct modeling and analysis,by means of the finite element method,of a multi-tube model of casing of different steel grades and a combination of different perforation parameters,under different environmental conditions(different internal and external pressure).The results show that under the same perforation parameter,the equivalent stress within the casing increases with the external pressure and the change is linear.Equavelent stress within the casing decreases drastically with the increase of internal pressure.When the internal pressure is greater than the external pressure,the equivalent stress of the casing tends to slow down.Stress condition in the casing perforation improves when internal pressure is applied in the casing.