A Numerical Analysis Study on the Reheating crack around Welded Joint of Pressure Vessel with 2<TEX>$frac {1}{4}$</TEX>Cr-1Mo Steel

J. Ocean Eng. Technol. 2000;14(1):88-94.

A Numerical Analysis Study on the Reheating crack around Welded Joint of Pressure Vessel with 2$frac {1}{4}$Cr-1Mo Steel

2$frac {1}{4}$ Cr-1Mo강 압력용기 Nozzle 용접이음부의 재열균열에 관한 수치해석적 연구

김종명

담양대학 기계·자동차공학부

Keywords: Pressure vessel, Welding residual stress, Reheating crack, Creep strain, Thermal-elasto-plasto-creep, Post welding heat treatment PWHT

핵심용어: 압력용기, 용접잔류응력, 재열균열, 크리프 변형율, 점열탄소성, 용접후열처리

Abstract

Recently various pressure vessels like an atomic reactor and plant facilities become more larger and are needed to bear in both very high temperature and pressure condition. And in making such a high pressure vessels the amount of annual usage of 2 $frac {1}{4}$ Cr-1Mo steels which are predominant to resist high temperature high pressure and corrosive circumstances are increasing. But despite of this advantage of 2 $frac {1}{4}$Cr-1Mo steel. when PWHT(post welding heat treatment) is carried out lots of reheating cracks are occur. In this reason it is strongly needed to study and examine the mechanical behavior of welded joints through welding to PWHT process. So in this study welded nozzle of pressure vessel where reheat cracks are frequently occur are selected for analysis the crack-occurrence mechanism.