MODERN TECHNOLOGIES OF STRENGTHENING THE WELDED SEAMS OF THIN -WALL PIPELINES
Keywords:
gas-supply pipe, weld seam, seam defects and damages, stress concentration, atmospheric influence, corrosion fatigue, surface plastic deformation, automatic device of hardening technologyAbstract
The structural change of the weld material seam of gas pipes in different cross-sections of the seam are considered. The external and internal weld defects have been classified, of which the most significant factor is the stress concentration in the transition zone of the weld to the base metal of the pipe. The analysis of atmospheric effects on the welded seams of pipelines initiating adsorption and electrochemical processes is carried out. A method for increasing the bearing capacity of pipelines is proposed with application of automatic technological operations on the outer surface of the weld and the transition zone to the pipe metal for grinding and surface plastic deformation using the special device, which creates residual compressive stresses that relieve the working tensile stresses in the stress concentration zone.
