Ceradyne manufacturers tube sheet boiler ferrules for use in the chemical processing industry. These ferrules, made from Ceralloy® 147-31N Silicon Nitride, are used in the manufacture of hydrogen cyanide. The performance benefits include resistance to severe thermal shocking and elimination of the metal dusting seen in inconel ferrules. Ceradyne’s tube sheet boiler ferrules have been designed for operation in a variety of boiler types that have successfully completed many more operating hours than other materials.