Predicting Fatigue Damage and Vulnerability of a Shunt Reactor Due to Structural Vibrations

Weld crack failures in structural steel fabricated parts of Shunt Reactors have recently been reported, even though these Reactors complied with conventional structural design practices as well as vibration limits as specified in applicable standards. These observations indicated that cyclic loads due to continuous vibrations can result in damages due to progressive fatigue in welded structural components, even if the measured vibration amplitudes are within prescribed limits. Such failures are not addressed adequately in traditional design, validation and verification approaches. Fillet weld joints in Shunt Reactor tank body and active part clamping structure are found to be vulnerable in particular. This is due to the metallurgical heterogeneity, residual stresses and local stress…