Volume 20, Issue 3 (May 1992)
Fatigue Behavior of (BS 1470 N8-0) Aluminum Alloy and (BS 1501–510) Nickel Steel Double-Fillet and Tee-Butt Welds (Subject to Bending)
The shell to base welds of liquefied natural gas (LNG) tanks are normally double fillet welds, although in some tanks teebutt welds are used. The fatigue behavior of these welds has been examined by testing 134 full-size specimens. The testing examined the low cycle, high strain performance of the welds in air at +20°C and in liquid nitrogen at −196°C. The results from this work have shown that double fillet weld and tee-butt weld fatigue performance are comparable. The low temperature fatigue performance matched or exceeded that under equivalent ambient conditions. The shell to bottom welds used in British Gas LNG tanks have fatigue lives well in excess of that required for operational duty.