The rolling simulation for cold work metal hardening

Abstract

This article describes the results of a calculation and experimental analysis of destructive physical phenomena that appear in critical sections of industrial and power-related equipment, and lead to occurrence of various operational damages. It was shown that pipeline welded connections are the sections most prone to crack development, therefore the traditional strength calculations need to be combined with fracture mechanics criteria and thorough materials analysis of flawing and structural imperfection. The cold work hardening technique was proposed as a solution for the problem of critical sections performance property restoration. The technique uses surface plastic deformation phenomenon to change the material’s throughthickness stress distribution. In order to optimise surface hardening for welded connections prone to defect formation, we proposed a simulation for analysing an actual pipeline sections load. To assess the applicability of the simulation results, the cold work hardening technique was developed and introduced using a full-scale test sample for damaged areas of welded connections in ø426×40 vent pipes at Novovoronezh NPP Unit No.5.