Libros UCLV { BETA }

The world of failure analysis began opening up to me about 30 years ago when, as a young engineer on a plant tour, I was shown a row of six 600-hp pumps that had broken 11 pump shafts in the previous 8 or so months. The pumps were impressive, but the fact that they were repeatedly breaking 6-in.-diameter shafts was just amazing to me. After many months of charting and analyzing motor power requirements, pump flow rates, liquid temperatures, and inspecting everything else we could think of, we eventually realized that the pumps were operating far back on their curve and fatigue pulses occurred every time a vane passed the cut water. The result of this cyclical loading, combined with the shaft corrosion, was causing the failures.