STDHydrotreater recirculation heater tube overheat rupture -> renewables diesel/hydrogen leak and fire
Mispositioned valve caused low-flow maldistribution + blocked combustion air duct reburn -> tube over-temperature rupture
The recorded code STD is an ISO 14224:2016 functional failure code (describes what the equipment failed to do). The damage mechanism (how it failed) is shown in the Mapping block above. The two are distinct dimensions in ISO 14224.
creep_bulgingCarburization carburizationFurnace Tube Oxidation / Spalling oxidation_spallingInternal Coking internal_cokingHot Spot hot_spotBend Thinning bend_thinningWeld Crack weld_crackHigh-temp Failure high_temp_failureOxidation oxidationDew Point Corrosion dew_point_corrosionFin Loss/Fouling fin_loss_foulingErosion erosionBurner Tip Plugging burner_tip_pluggingFlame Impingement flame_impingementIgnition Failure / Flameout ignition_failurePilot Outage pilot_outageTC Failure tc_failureStack Corrosion stack_corrosionLining Loss lining_lossDamper Sticking damper_stickingActuator Failure actuator_failureFan Imbalance fan_imbalanceBearing Failure bearing_failureLens Fouling lens_foulingElectronics Failure electronics_failureValve Seat Leakage seat_leakageActuator Failure actuator_failure_2Refractory Spalling refractory_spallingRefractory Lining Thinning -> Shell Over-temperature (Hot Spot) hot_spot_on_shell结垢/堵塞 MECH-FOULING保温层下腐蚀 MECH-CUI热疲劳 MECH-THERMAL-FATIGUE湿硫化氢损伤 MECH-WET-H2S蠕变与应力破裂 MECH-CREEP酸性水腐蚀 MECH-SOUR-WATER锅炉水/凝结水腐蚀 MECH-BWC高温硫化氢/氢腐蚀 MECH-HT-H2S高温氧化 MECH-OXIDATION硫化腐蚀 MECH-SULFIDATION冲蚀/冲刷腐蚀 MECH-EROSION硫氢化铵腐蚀 MECH-ABS均匀/局部减薄（通用减薄） MECH-THINNING烟气露点腐蚀 MECH-DEWPOINT大气腐蚀 MECH-ATMOS