Study On Residual Strength Of Pressure Pipeline With Corrosion Defects

With the increase in working hours of oil and gas pipelines,corrosion will inevitably occur on the wall of the pipeline,which will weaken the strength and shorten the life of the pipeline.Therefore,it is necessary to study the residual strength of the corrosion pipes.According to the experimental data of the blasting pipelines,establish 3D models with Solid Works,and import the 3D models into ANSYS to redraw and calculate.The simulation results are compared with the blasting experimental data and the calculations of four standards,including ASME B31G?SY/T 6151?PCORRC and DNV-RP-F101,to verify the accuracy of the ANSYS model.Using ANSYS to simulate the influence of single corrosion on failure pressure,including the depth,length and width of corrosion defects.And verify that the long corrosion pipes can be simplified into 2D models in calculation.Using the 1st Opt software to fit 225 sets of data,to obtain a new model for calculating the failure pressure of the corrosion pipe.The results of the fitting formula are compared with the four standards,the average error of the fitting formula is the minimum.So we can use the fitting formula instead of the finite element method to calculate the failure pressure of single corrosion pipes.Using ANSYS to simulate the axial,circumferential and composite double-point corrosion pipelines,to study the influence of corrosion size and corrosion distance on failure pressure.Determine the critical distance of double point corrosion.And finally,the failure pressure calculation method of the double corrosion pipe is obtained.The results of the fitting formula are compared with the blasting experiments and the DNV-RP-F101 method to verify the accuracy of the formula.Compile a software named "Evaluate the residual strength of the corrosion pressure pipes".This software includes six kinds of single corrosion and two kinds of double corrosion methods to calculate the failure pressure,which can facilitate the evaluation of the residual strength of corrosion pipes greatly.