The employment of high temperatures and a corrosive environment when processing ethane, nafta and other petrochemical products requires the use of specialized alloy materials compatible within the stringent operating conditions of erosion, oxidation and wear. Chemical reactions occurring on the inner diameter of the tubulars create an irreparable impact on the metal surface, damaging the material and thus, decreasing the production rates of petrochemical plants. The coating of these tubes introduces a significant performance increase. Engineered EPVD® coatings applied to the inner diameter of tubulars protect the exposed metal surfaces from high temperature and corrosion and increase the throughput of the installation, which transforms into a significant saving if applied industry-wide. The process forms high quality diffusion coatings of multiple materials and/or alloys for extreme chemical environments in upwards of 1200° C.
Surface Engineering for the Ethylene Industry Coking is a large and growing problem in the Ethylene Industry. Coking damages tubes and reduces furnace performance. CoatAlloy™ is an engineered coating system which provides the necessary surface characteristics to mitigate catalytic coke formation. CoatAlloy™ is:
- Inert top layer
- Continuous and adherent surface oxide
- Able to regenerate under pyrolysis conditions
- Stable at high temperatures
- Impervious to carbon
Tube inner surface coated with CoatAlloy™ utilizing the EPVD® process satisfy the demands of Ethylene service by providing a continuous, adherent inert surface that mitigates catalytic coke formation.
The CoatAlloy™ coatings resist carburization which brings about changes in creep strength, ductility and toughness. They are self healing and have sufficient hardness and toughness to resist erosion by coke particles; they also withstand the thermal shock and cycling inherent in decoking.