ASM Failure Analysis Case Histories: Pulp and Paper Processing Equipment
Corrosion-Fatigue Cracking in Steam Accumulators
Three examples of corrosion-fatigue cracking from the toes of substantial fillet welds applied to seal-leaking riveted seams in steam accumulators are described. In the first case, this practice resulted in a disastrous explosion; in the second, which involved two identical vessels at the same location, cracking in course of development was discovered during internal inspection. Microscope examination of several specimens cut to intersect a crack showed it to be typical of corrosion-fatigue; it was in the form of a broad fissure, contained oxide deposits, and the termination was blunt-ended. The two cases not only serve to illustrate the danger of applying fillet welds to seal the lap edges of riveted seams, but point to the inadvisability of employing riveted construction for vessels intended for service under conditions involving frequent pressure and thermal fluctuations, as it is extremely difficult to maintain the tightness of riveted seams under these conditions. Such vessels are now almost exclusively of all-welded construction
Corrosion-Fatigue Cracking in Steam Accumulators, ASM Failure Analysis Case Histories: Pulp and Paper Processing Equipment, ASM International, 2019, https://doi.org/10.31399/asm.fach.pulp.c9001393
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New Handbook: Volume 11B
Volume 11B serves as a reference and guide to help engineers determine the causes of failure in plastic components and make corrective adjustments through design and manufacturing modifications.