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CSB Investigation Report No. 2010-08-I-WA 2010 Safety Safety
Tesoro Anacortes Refinery Heat Exchanger HTHA Rupture and Explosion
Tesoro Anacortes Refinery, Anacortes, Washington
Related equipment → Shell-and-tube heat exchanger (shell_tube_heat_exchanger)
7Fatalities
0Injuries
Corrosive ruptureMechanism code STD
⌗Failure Mode · ISO 14224 Mapping
Damage mechanism (recorded in KB)
Corrosive ruptureSTD
ISO functional code (as recorded)
ISO 14224:2016 functional failure code
STD · Structural failure
ISO STD — Structural failure.
1What Happened

Naphtha hydrotreater heat exchanger carbon-steel shell degraded by high-temperature hydrogen attack (HTHA); catastrophic in-service rupture, explosion and fire

2Root Cause

Carbon-steel exchanger shell in long-term high-temperature hydrogen service suffered HTHA; industry practice (API RP 941 Nelson curves) insufficient to prevent it — rupture and explosion killed 7 employees

3Reliability Lessons (from investigation root cause)
  • The 'Root Cause' above is the core lesson of this accident; not split further.
4Associated Failure Mechanisms (Keywords)
heat exchanger HTHA high-temperature hydrogen attack rupture explosion carbon steel naphtha hydrotreater
About the Failure-Mode Code (click to expand)

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.

5Evidence Source (transparent)
Authority：U.S. Chemical Safety and Hazard Investigation Board (CSB)
Official Report：www.csb.gov ↗
Data Verification：verified_url_csb_case_page_curl200
↗Related Failure Modes · Traceability
Fouling/Plugging fouling_pluggingCorrosion Thinning corrosion_thinningErosion erosionStress Corrosion Cracking (SCC) sccFlow-induced Vibration Fatigue (Tube) flow_induced_vibration_fatigueExpanded Joint Leak expanded_joint_leakTube Sheet Corrosion tube_sheet_corrosionTube Hole Enlargement tube_hole_enlargementCladding Disbonding cladding_disbondingPartition Leak partition_leakChannel Flange Leak channel_flange_leakShell Internal Corrosion / Erosion fmShell Crack fm_2Baffle Corrosion / Wear -> Loss of Tube Support fm_3Baffle Vibration Fatigue fm_4Fatigue Cracking fatigue_crackingCorrosion Thinning fm_5Gasket Aging / Creep -> Leak fm_6Improper Gasket Installation fm_7Bolt Relaxation bolt_relaxationBolt Corrosion fm_8Valve Internal Leak fm_9Blockage fm_10Relief Valve Set-pressure Drift fm_11Valve Seat Leak fm_12Inlet Line Blockage fm_13Sensor Drift fm_14Loose Wiring / Terminals fm_15Fouling/Plugging fouling_pluggingCorrosion Thinning corrosion_thinningErosion erosionStress Corrosion Cracking (SCC) sccFlow-induced Vibration Fatigue (Tube) flow_induced_vibration_fatigueExpanded Joint Leak expanded_joint_leakTube Sheet Corrosion tube_sheet_corrosionTube Hole Enlargement tube_hole_enlargementCladding Disbonding cladding_disbondingPartition Leak partition_leakChannel Flange Leak channel_flange_leakShell Internal Corrosion / Erosion fmShell Crack fm_2Baffle Corrosion / Wear -> Loss of Tube Support fm_3Baffle Vibration Fatigue fm_4Fatigue Cracking fatigue_crackingCorrosion Thinning fm_5Gasket Aging / Creep -> Leak fm_6Improper Gasket Installation fm_7Bolt Relaxation bolt_relaxationBolt Corrosion fm_8Valve Internal Leak fm_9Blockage fm_10Relief Valve Set-pressure Drift fm_11Valve Seat Leak fm_12Inlet Line Blockage fm_13Sensor Drift fm_14Loose Wiring / Terminals fm_15
Report No. 2010-08-I-WA · Data from CSB public investigation conclusions, compiled by Reliability AI, for reliability demonstration purposes only. This case is derived from public incident investigation reports for learning purposes only. AIM does not endorse or guarantee its accuracy.