NORTHERN NATURAL GAS CO
gas_transmission Incident — — June 17, 2017
Incident Information
| Incident Date | June 17, 2017 |
| Operator | NORTHERN NATURAL GAS CO |
| Commodity | NATURAL GAS |
| Pipeline Type | gas_transmission |
Location
| State | |
| Coordinates | 44.64276, -93.16182 |
Cause
| Cause | EQUIPMENT FAILURE |
| Subcause | MALFUNCTION OF CONTROL/RELIEF EQUIPMENT |
Casualties
| Fatalities | 0 |
| Injuries | 0 |
Costs
| Property Damage | $0 |
| Emergency Response | $0 |
| Other Costs | $0 |
Location Map
Incident Narrative
"THE FARMINGTON B DISCHARGE BLOW DOWN VALVE OPENING EVENT ON 6/17/2017 WAS CAUSED BY THE PILOT CONTROLLED ESD 3-WAY POPPET VALVE TO IMPROPERLY SEAL/PREVENT POWER GAS FROM REACHING THE MAIN VALVE OPENING CONTROL CIRCUIT. THE PURPOSE OF THE PILOT VALVE IS TO CONNECT THE POWER GAS PORT TO THE OPENING CONTROL PORT ONLY IF/WHEN ESD PILOT IS REMOVED FROM THE CIRCUIT BLOCK. THE 'AS FOUND' CONDITION OF THE PILOT VALVE, CLEARLY TESTED AN OPEN PATH BETWEEN THE TWO PORTS, EVEN WITH NORMAL ESD PILOT GAS PRESENT (NON-ESD CONDITION). FURTHER REVIEW OF THE POPPET VALVE ASSEMBLY SUPPORTED THE FAILURE WAS DUE TO END OF LIFE-CYCLE FOR THE SOFT COMPONENTS (POPPET VALVE/O-RINGS). THE POPPET VALVE IS TUBED IN A DEAD-LEG CONFIGURATION AND ONLY FLOWS DURING ESD ACTUATION, LAST ACTUATION/TEST WAS SUCCESSFULLY DONE SO IN SEPTEMBER OF 2016. NORMALLY THE VALVE IS OPERATED ONCE YEAR DURING THE ANNUAL STATION ESD TEST. A NEW ESD CONTROL POPPET VALVE WAS INSTALLED AND TESTED ON THE ACTUATOR AND PLACED INTO SERVICE ON 6/17/2017."
About This Pipeline Incident
Pipeline incident data is reported to the Pipeline and Hazardous Materials Safety Administration (PHMSA). All significant incidents involving fatalities, injuries, or property damage over $50,000 must be reported.