2019 Spring Meeting and 15th Global Congress on Process Safety
(120c) Fitness-for -Service Steam Super Heater Coil
Authors
Thomas Garza, Chevron Phillips Chemical Company, LP
Cliff Knight, Knighthawk Engineering
Carlos Corleto, Knighthawk Engineering
Abstract:
Chevron Phillips Chemical Company, LP (CPC) operates a Steam Superheater at the ethylene plant in Port Arthur, Texas. The Superheater receives saturated steam from the ethylene cracking furnaces and superheats it so that it can be used to drive high horsepower turbines. The superheater experienced a temperature excursion in the 1 ¼ Chrome radiant coils and was evaluated to determine if the tubes were acceptable for further safe operation. The coil outlet temperature increased to 1350° F, which would correspond to a tube metal temperature inside the superheater more than 1400° F during the excursion. This temperature is above what is allowed by ASME Section I.
The coil was evaluated using several non-destructive evaluation techniques including metallographical replicas, visual assessment, thickness measurements, and hardness measurements. In addition, a fitness for service assessment per API 579/ASME FFS-1, 2007 was performed. This paper presents the results of the evaluation that was used to ensure that the integrity of the pressure boundary is maintained while the superheater continues to operate until the next scheduled opportunity for inspection or replacement.
Chevron Phillips Chemical Company, LP (CPC) operates a Steam Superheater at the ethylene plant in Port Arthur, Texas. The Superheater receives saturated steam from the ethylene cracking furnaces and superheats it so that it can be used to drive high horsepower turbines. The superheater experienced a temperature excursion in the 1 ¼ Chrome radiant coils and was evaluated to determine if the tubes were acceptable for further safe operation. The coil outlet temperature increased to 1350° F, which would correspond to a tube metal temperature inside the superheater more than 1400° F during the excursion. This temperature is above what is allowed by ASME Section I.
The coil was evaluated using several non-destructive evaluation techniques including metallographical replicas, visual assessment, thickness measurements, and hardness measurements. In addition, a fitness for service assessment per API 579/ASME FFS-1, 2007 was performed. This paper presents the results of the evaluation that was used to ensure that the integrity of the pressure boundary is maintained while the superheater continues to operate until the next scheduled opportunity for inspection or replacement.