Abstract:
Propagation of cracks was detected in an exhaust system that is manufactured with an austenitic stainless
steel (AISI 316L). Usually cracks propagate from weld toes of butt and fillet weld joints located near the
lower support ring of the structure. An in-service strain spectrum was collected with a high-temperature
spot-welded strain gauge and temperature distribution was monitored with eight thermocouples spotwelded
on the critical region of the exhaust system. A pressure spectrum was also acquired at its outlet
section. A redesigned geometry of the structure was analysed by finite element method and its fatigue life
assessed.