NTSB Safety Recommendation P-77-030

NTSB safety recommendation P-77-030.

INCLUDE, IN EMERGENCY SHUTDOWN SYSTEMS, A SEPARATE CONTROL TO REMOTELY OPERATE VALVES THAT CAN INDEPENDENTLY BLOW DOWN THE STATION PIPING.

Priority: CLASS II

Overall Status: Closed - Acceptable Action

Issued Date: 1977-10-31

Adopted Date: 1977-10-13

Overall Date Closed: 1978-09-28

Synopsis: ON DECEMBER 7, 1976, A NATURAL GAS COMPRESSOR FAILED AND THEN EXPLODED AND BURNED AT AN EXXON GAS SYSTEM, INC., STATION NEAR ROBSTOWN, TEXAS. AN EMERGENCY SHUTDOWN SYSTEM WAS ACTIVATED, BUT FOUR AUTOMATED FIRE GATE VALVES DID NOT CLOSE. ANOTHER EMERGENCY CONTROL SYSTEM ALSO FAILED TO AUTOMATICALLY CLOSE THE SHUTOFF VALVES, LEADING TO TWO OF THE FIVE COMPRESSORS IN THE STATION. A SECOND EXPLOSION OCCURRED WITHIN THE BURNING BUILDING. THE FIRE KILLED ONE PERSON, INJURED TWO PERSONS, AND DESTROYED THREE ENGINE-DRIVEN COMPRESSORS AND THE COMPRESSOR BUILDING.

Keywords: Remote Operated Valves

Ntsbnumber: DCA77MP005

Report Number: PAR-77-03

Addressee Name: ExxonMobil Corporation

Addressee Status: Closed--No Longer Applicable

Addressee Date Closed: 1978-09-28

Addressee Organization Type: P-Private Industry

Communication Date: 1977-12-20

Communication Type: Official Correspondence

Communication Contents: EXXON GAS SYSTEM LTR: STATION 1 IS BEING COMPLETED WITH A SYSTEM WHICH INCORPORATES A MANUAL, REMOTE CONTROL POWERED BY A SEPARATE DEDICATED NITROGEN SUPPLY. INSTALLATION IS 90% COMPLETE ON STATION 1. AFTER TESTING AND DEBUGGING AT STATION 1, THIS DESIGN WILL BE USED AT ALL OTHER STATIONS. 5/12/78 - EXXON RESPONSE TO NTSB LETTER OF 4-27-78 : THE MODIFICATION OF THE STATION 1 INDEPENDENT BLOWDOWN VALVES TO INCLUDE REMOTE ACTUATION BECAME OPERABLE PRIOR TO 4-28-78. MODIFICATIONS HAVE ALSO BEEN COMPLETED AT STATIONS 2,3, AND 4 TO PERMIT REMOTE BLOWDOWN OF STATION PIPING. THE BLOWDOWN VALVES AT ALL OTHER STATIONS ARE OPERATED BY SEPARATE CONTROL SYSTEMS WITH OPERATION INITIATED BY THE FULL CLOSURE OF ALL FIRE GATE VALVES AT THE RESPECTIVE STATIONS. THEREFORE, EACH OF OUR STATIONS ARE ABLE TO HAVE REMOTE BLOWDOWN OF STATION PIPING.

Addressee Organization Type: P-Private Industry

Communication Date: 1979-01-05

Communication Type: Official Correspondence