Estimation of the influence of a defect on the operational suitability of a pipeline

A finite-element model of a pipe header with a defect in the metal wall was created in the ANSYS software complex. The boundary conditions consider the hinging of the ends of the section from linear displacements. The calculation is based on the procedure of the allowable conditional elastic stresses. Values of equivalent stresses arising in the defective pipeline from the operational loads are obtained. Analysis of the obtained stresses in comparison with the allowable values is given based on the calculated resistance of steel. It is established that a dent in the pipeline causes a local stress perturbation. Thus, an increase in equivalent stresses in the region of the maximum depth of the dent amounted to 1.3% in comparison to the vicinity of the defect. Maximum values of membrane, tangential, and equivalent stresses do not exceed the design resistance. A conclusion is drawn on the influence of the dent-type defect on the operational suitability of the pipeline under study.