ONEOK NGL PIPELINE, LLC

Incident Narrative

ONEOK'S PIPELINE CONTROL CENTER SCADA SYSTEM RECEIVED A STATION SHUTDOWN DUE TO GAS DETECT AT APPROXIMATELY 12:34 PM ON 1/20/2015 FOR ONEOK SHAWNEE PUMP STATION. LOCAL ONEOK FIELD REPRESENTATIVE WAS CONTACTED AND RESPONDED TO THE LOCATION WHERE HE FOUND THE 1/2 INCH STAINLESS STEEL TUBING CONNECTED TO THE OUTBOARD SEAL ON PUMP #3 HAD FAILED. EMPLOYEE ISOLATED THE PUMP AND LOCKED IT OUT OF SERVICE. PUMP STATION WAS THEN PLACED BACK IN SERVICE WITHOUT PUMP #3. ONEOK'S INVESTIGATION FOUND THE TUBING HAD FAILED AT THE FERRULE CONNECTION AND IT WAS BELIEVED THE FAILURE WAS CAUSED BY OVER TIGHTENING OF THE FITTING. AFTER THIS FINDING ALL STAINLESS STEEL TUBING ON ALL PUMPS AT THE STATION WAS REPLACED AND ALL FITTINGS WERE TIGHTENED FOLLOWING MANUFACTURES SPECIFICATIONS. ONEOK IS CONTINUING TO INVESTIGATE TO SEE IF VIBRATION, HARMONICS, LACK OF ADEQUATE SUPPORT OR OTHER FACTORS MAY HAVE CONTRIBUTED TO THE FAILURE. 4/23/2015 ONEOK INVESTIGATION DETERMINED TUBING FITTING HAD BEEN OVERTIGHTENED. THE FAILED TUBING WAS SENT TO OUTSIDE PARTY, (I2C), THAT DETERMINED FAILURE WAS CAUSED BY OVERTIGHTENING. ONEOK EMPLOYED PARKER HANNIFIN CORPORATION PERSONNEL (STAINLESS STEEL TUBING FITTING MANUFACTURE) TO TRAIN ONEOK INSTRUMENTATION AND ELECTRICAL TECHNICIANS ON INSTALLATION PROCEDURES OF TUBING FITTINGS. TRAINING WAS COMPLETED IN MARCH OF 2015. ONEOK ALSO REVIEWED THE STAINLESS STEEL TUBING INSTALLATION AT THE SHAWNEE PUMP STATION AND INSTALLED ADDITIONAL SUPPORTS.