Case Study on Hydrocracking Reactor Inspection after an Emergency Shutdown
SourceSince 1973 hydrocracking reactors have been operating in the oil refinery of Salamanca, Mexico. These reactors are composed basically of 2¼Cr-1Mo steel, overlaid with 347 stainless steel, of 262 mm total thickness. In early 1979 one of these reactors experienced an emergency shutdown caused by a fire originating in the recirculation pump. In this paper several observations made during a field inspection are presented. It was found by ultrasonic methods that some parts of the reactor suffered overlay separations, including a total of about 12 percent of the surface area on the first ring. Metallographic analysis was carried out to find whether the material had suffered damage due to the emergency cooling conditions. Possible causes of the overlay separation and its behavior after re-starting operations are reported.