TRANSCONTINENTAL GAS PIPE LINE COMPANY
gas_transmission Incident — — April 16, 2024
Incident Information
| Incident Date | April 16, 2024 |
| Operator | TRANSCONTINENTAL GAS PIPE LINE COMPANY |
| Commodity | NATURAL GAS |
| Pipeline Type | gas_transmission |
Location
| State | |
| Coordinates | 41.26013, -77.22886 |
Cause
| Cause | EQUIPMENT FAILURE |
| Subcause | MALFUNCTION OF CONTROL/RELIEF EQUIPMENT |
Casualties
| Fatalities | 0 |
| Injuries | 0 |
Costs
| Property Damage | $1,047,629 |
| Emergency Response | $0 |
| Other Costs | $0 |
Location Map
Incident Narrative
"ON 4/16/2024, OPERATIONS WERE PERFORMING VALVE MAINTENANCE ON PL-115 GATE VALVE (WKM VALVE WITH AN EIM ACTUATOR). DURING THE CLOSE ACTUATION, THE VALVE FAILED TO STOP CLOSING WHEN COMMANDED AND RESULTED IN THE ACTUATOR BEING PUSH OFF THE STEM AND INTO THE GROUND. THE END OF STROKE/LIMIT VALVE FAILED TO ISOLATE POWER GAS AFTER CLOSE, RESULTING IN ADDITIONAL TORQUE ENERGY BEING APPLIED TO THE GEARS HOUSING. ALL THAT ENERGY RESULTED IN THE FAILURE OF THE CAST IRON WELDS BETWEEN THE ACTUATOR AND YOKE/STEM HOUSING. WITH THE GEAR HOUSING OFF THE SHAFT, THE GATE VALVE COULD NOT REMAIN CLOSED AND PIPELINE PRESSURE SLAMMED IT OPEN AGAINST THE BONNET. AS A RESULT OF THE ACTUATOR FAILURE, A STAINLESS POWER GAS LINE BROKE OFF AND VENTED. THE EIM ACTUATOR CONTROLS WERE TESTED ON A BENCH WITH PRESSURIZED AIR AND DISCOVERED TO SUCCESSFULLY ACHIEVE THE OPEN LIMIT BUT NOT THE CLOSE LIMIT. THE CAUSE FOR THIS WAS THE CLOSE LIMIT VALVE WAS INSTALLED BACKWARDS, WHICH RESULTED IN THE POPPET BEING UNABLE TO ENGAGE WITH THE CAM AND FAILURE TO ISOLATE POWER GAS TO THE MOTOR ONCE THE VALVE WAS CLOSED."
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.