Event
- Event ID
- 1057
- Quality
- Description
Release from a welding of a hydrogen transmission pipeline
At 12:45 pm the operation control centre (OCC) recognised that a customer flow and pressure dropped significantly.
At 13:28 the OCC made the decision to close the upstream remote operated valve.
At 15:00 the pipeline technician arrived on site and confirmed the breach in the pipeline.
Additional pipeline operations technicians were deployed to isolate both manual block valve upstream and downstream of the incident site.- Event Initiating system
- Classification of the physical effects
- Hydrogen Release and Ignition
- Nature of the consequences
- fire
- Macro-region
- North America
- Country
- United States
- Date
- Component involved
- pipeline (weld)
- Failure mode
- rupture & ignition
- Initiating cause
- H2-driven material degradation
- Root CAUSE analysis
The initial cause was the complete failure of a pipe girth weld, probably at the heat-affected zone, by hydrogen induced cracking.
- Root causes
- Date entry in HIAD
- 01/07/2024
Facility
- Application
- Hydrogen transport and distribution
- Sub-application
- Pipeline
- Hydrogen supply chain stage
- All components affected
underground pipepine,welding
- Process temperature range [C]
- ambient temperature (-50°C to +50°C)
- Process pressure range [MPa]
- medium pressure (2 to 10 MPa)
- Location type
- Underground
- Location
- countryside or desert
- Operational condition
- Description of the facility/unit/process/substances
DESCRIPTION OF THE FACILITY
The pipeline had been installed in 1992. it was made of carbon steel, with a Max operative pressure of 375 psig. At the moment of the incident the pressure was 374 psig.
Gas flow was 7284 mcf
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
- Currency
- US$
- Property loss (onsite)
- 500.948
- Post-event summary
No consequence to environment or persons. Only costs related to materials damage and emergency intervention.
- Emergency action
Both manual block valve upstream and downstream of the incident site were blocked.
Local and federal first responders intervened (unknown their actions)
136 thousand standard cubic feet went lost during the leak (unintentional release)
In-depth data
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Released amount (kg)
- 322
- Release temperature [°C]
- 25
- Release pressure [MPa]
- 2.3
- Probable IGNITION SOURCE
References
- Sources categories
- PHMSA
- Reference & weblink
US Pipeline and Hazardous Materials Safety Administration PHMSA:
https://www.phmsa.dot.gov/safety-reports/pipeline-failure-investigation…
