Thermowells for use in Fluid Catalytic Cracking Units Applications

A spray coating for thermowell temperature assemblies has been developed that increases the life of thermowells in critical Fluid Catalytic Cracking Units (FCCU) in oil refineries, whilst also reducing maintenance and repair costs.

The SDC-4 plasma flame sprayed coating from Okazaki Manufacturing Company (Japan) is applied to the tip of its thermowells for use in FCCU applications, providing excellent corrosion resistance in harsh operating temperatures and pressures. At Fuji Oil Company in Japan, the SDC-4 plasma coating thickness on an FCCU thermowell tip had eroded by just 0.1mm during 51 months of operation. Mounted in the FCCU reactor stripper riser extension, with operating temperatures of 510 deg C and operating pressures of 0.27Mpa, the thermowell was manufactured from Inconel600, with a 16mm OD and an SDC-4 coating thickness of 2mm.