Afterthoughts on a Cheap Lesson

You might ask, What would the PSM regulation require A portable sandblast rig would normally not be included in the covered process within a refinery or chemical plant. But, a facility that had such PSM programs would probably have influences in the Mechanical Integrity area that encourages strict adherence to welding procedures and emphasizes use of original manufacturers methods and standards. 

Piping system changes occur frequently within major chemical plants. This section covers incidents involving piping changes in which piping specifications were not strictly utilized. 

A Small Piping Modification—For Testing the Line—Helped Create a Failure Point 

Refinery employees observed a noticeable leak on a 1-inch (2.5 cm) connection above a discharge header in a refinery. While carefully removing insulation around the leak to better observe the leak source, the mechanic aggravated the situation, and a threaded nipple and valve blew off. A stream of hot oil slurry (670° F (354° C)) sprayed the area and produced a dense cloud of heavy hydrocarbon mist. Oil sprayed over 90 ft. (27 m) into the air and the mist covered an extensive area of the refinery. [9] Immediately after the oil mist cloud formed, operators initiated a shutdown of the unit, and the alert team started the fire-water monitors. The hydrocarbon mist ignited about 10 minutes after the threaded nipple blew off. Responders extinguished the blare within about 90 minutes. Luckily, only a portion of the total volume of escaping oil burned. 

Employees questioned if there were more of these potential surprises on piping hidden beneath the insulation. The refinery instituted a two-part program to eliminate additional hidden hazards to avoid similar troubles. A fist of likely pipeline hazards was assembled, and a technical staff member accompanied the foreman in an inspection tour of each operating area. The unit foreman assisted in the inspection. 

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