Abstract
Though it is often necessary to perform repair welding in structures already constructed, welding under pulsating stress or oscillation is considered to be undesirable for operative weldability and crack sensitivity. In this study, welding crack test was carried out for HT-60 to survey the possibility of welding under pulsaring stress in bridges, offshore structures and power transmission lowers, etc.
The results obtained are as follows:
1) Tne crakes detected in welded joint under pulsating, stress are classified into solidification crack and root hot crack in weld metal.
2) The solidification crack arises under high stress frequency and high stress range.
3) The critical stress range for root hot crack is smaller than that for solidification crack, and it decreases under decrease of stress frequency and increase of heat input.
4) It was clarified that the welding under pulsating stress is possible when the restrain intensity of weld joint, stress range, groove length and stress frequency is known.
