Popis: |
Evaluating the behavior of coke drums is challenging due to the randomness and uncertainties in typical cyclic loading conditions. Severe fluctuations in temperature and stress during the quench portion of the thermal cycle can often lead to distortion, fatigue damage, and ultimately, cracking. Since the evolution of damage in the coke drums is a cycle-dependent process, a snapshot of strain or distortion data generally has limited value in quantifying remaining life. Advanced fatigue methods and damage models are usually required to address the permanent irreversible damage and material degradation that is produced throughout multiple cycles. This paper represents an advanced finite element analysis (FEA)-based study that is a continuation of the work published in PVP2017-65807[1], with new coke drum support skirt geometries included in the comparisons. The thermal-mechanical behavior of five different support skirt designs; Egg-in-Cup, Tangential, Forged, Sliding, and Welded, are investigated, and relative fatigue life predictions are discussed for each type of design using consistent, idealized thermal transients. |