COMPUTATIONAL AND EXPERIMENTAL STUDY OF THE STRESS-STRAIN STATE OF A PIPE UNDER EXTERNAL RADIAL LOAD, INTERNAL PRESSURE AND TEMPERATURE DIFFERENCE

Abstract

Oil and gas pipelines are subjected to complex of loads and impacts during operation. The purpose of this article is an experimental assessment of the stress-strain state of a pipe under the action of external radial force on a laboratory bench by the strain gauge method, as well as a computational and experimental assessment of the stress-strain state under the combined action of radial force, internal pressure and temperature difference. Accounting for internal pressure and temperature difference (other factors affecting the pipeline) is carried out using well-known theoretical formulas which are confirmed by practice. The total stresses from the effects of several factors of influence are determined due to the principle of superposition.Experimental and computational studies of the stress-strain state of the pipe cross section under the influence of external radial force corresponding to the pipe deflection from 0 to 8 mm; internal pressure from 0 to 14 MPa; temperature difference from minus 60 C to 60 C have been carried out. Graphs of the dependence of maximum stresses on the factors of influence are constructed. Empirical formulas have been obtained for calculating the maximum equivalent von Mises stress of the cross-section of the pipe with a diameter of 325 mm under various loading options, they are necessary to assess the strength of the pipeline structure.