(Part 1 of 5) - Muhammad Abduh (abduh@reksolindo.co.id)
As key chain in world energy supply, the industry within oil and gas production, hydrocarbon refinery, storage and distribution, and power plant industry strive to achieve the highest level of integrity and reliability of their facilities, structures, tool and equipment system. Industry stakeholders that ranging from oil and gas producer, engineering, procurement, contractors, material suppliers, and inspection companies from day to day improve the quality standards, discovering new tehcnologies, develop new techniques and methodologies in order to raise the engineering integrity for the improvement of safety for people , environment conservation, and securing economic investment.
Tak ada gading yang tak retak. As an ancient Indonesian proverb is also happened to engineering structure: there will be no design without flaw and there will be no construction without defect. Failures sometimes occur. In several cases the aftermath of failures have a significant impact to the people safety and economic risk. But industry gain a valuable experience each accident occurs. There always be opportunities to improve operation procedures, value perceptions, technical code revisions, and regulatory improvements.
This publication as a result of literature work is aimed is to develop an alternative engineering failure database associated with material failures,corrosion, design flaw and construction defect that lead to material failure in oil and gas production, hydrocarbon industry, oil and gas distribution network, and energy power plant.
1. Umm Said Qatar - April 3, 1977 (Weld Failure, Gas Processing Plant, 3 killed, US$ 76,350,000/179,000,000)
A tank containing 236,000 barrels of refrigerated propane at 45 °F failed at weld. Near-miss-accident a year earlier reported at similiar tank weld caused 14,000 barrels of propane released. The possible cause of weld failure was corrosion by the influence of sulphate reducing bacteria that remained inside the tank after hydrotest with seawater. The wave of liquid propane swept over the dikes before igniting a near tank contained 125,000 barrels of buthane. It took eight days to completely extinguished the fire. (Source, Location)
2. Abqaiq Saudi Arabia - April 15, 1978 (Corrosion, Gas Processing Plant, US$ 53,700,000/117,000,000)
A 22-inch pipe operated at 500 psig in gas transmission system corroded and releasing vapor cloud. The first ignition occured from a flare 1,500 feet downwind. The second ignition occured when jet whipped pipe section struck the vapor space of a 10,000 barrels spheroid tank. (Source, Location)
3. Ekofisk Norway - March 27, 1980 (Weld Failure, Offshore Platform, 123 killed)
Alexandra L Kielland Platform, a semi-submersible oil drilling platform located at Ekofisk field North Sea capsized during a storm. The platform supported by five columns standing on five 22 meter diameter pontoons. The five 8.5 diameter columns on the pontoons were interconnected by a network of horizontal bracings. The cracked bracing made five other bracing broke off due to overload, and the vertical column connected with the cracked bracings became separated from the platform. The platform subsequently became unbalanced and capsized.
The investigation showed that a fatigue crack had propagated from the double fillet near the hydrophone mounted to one of the horizontal bracing. Some cracks related to lamellar tearing were found in the heat affected zone (HAZ) of the weld around the hydrophone. Learning from this accident some countermeasures were undertaken including the amendment of the standards in for stability, motion characteristics, manueverability, watertight doors, and structural strength in Mobile Offshore Drilling Units (MODU) Code by the International Maritime Organization. (Source 1, 2)
4. Edmonton Canada - April 18, 1982 (Fatigue, Petrochemical Plant, US$ 21,000,000/33,000,000)
Vibration from the reciprocating compressor was believed causing transverse fatigue of 1/8 stainless steel instrument tubing. High pressure ethylene released causing a fire by static electricity ignition. Although the compressor building equipped with gas detection system the gas release was not accurately relayed to the control room. Automatic fail-safe valves functioned properly by blocking the flow of more ethylene which was up to 11,000 pounds of gas already released causing damage to this low density polyethylene plant. (Source)
5. Remeoville Illinois US- July 23, 1984 (Weld Failure, Refinery, 17 killed, US$ 191,000,000/273,000,000)
A vessel for monoethanolamine absorber was constructed ten years earlier with one-inch thick ASTM A516 Gr 70 steel plates rolled and welded with full submerged arc without post weld heat treatment. Just prior to rupture a 6- inches crack detected at circumferential weld and by the time operator close inlet valve crack spread to 24 inches. The area was already cleared for evacuation and when fire brigade arriving the explosion occured. This explosion created sequential fire and explosion within refinery plant. A boiling liquid expanding vapor exposion (BLEVE) occured in a alkylation unit vessel.
Technical investigation pointed that crack initiated at HAZ of welded shell of the column by hydrogen cracking, and progressed by the mechanism of hydrogen induced stepwise cracking (HISC). Test according to NACE procedure confirmed that material was susceptible to HISC. (Source 1, 2)
6. San Juan Ixhuatepec Mexico City Mexico - November 19, 1984 (Pipe Leaking, LPG Terminal, 650 killed 64,000 injured, US$ 19,940,000/29,000,000)
A 12-inches pipeline between cylinder and sphere storage ruptured. Initial blast caused a series of BLEVEs. The oustanding cause of escalation was the ineffective gas detection system and as a result of lack of emergency isolation. This explosion and fire is perhaps the most devastating incident ever. The high death toll was due to the proximity of the LPG terminal to residence complex. Until now there is no clear information about the cause of pipe rupture. (Source 1, 2)
7. Las Piedras Venezuela- December 13, 1984 (Hydrogen Embrittlement, Refinery, US$ 62,076,000/89,000,000)
A fracture occured in 8-inch line carrying hot oil from hydrode sulfurizer. Crack found in heat affected zone about 1 - 1/2 inches from weld. Hot oil at 700 psi and 650 oF sprayed and ignited at the hydrogen units. Fire causing sequential rupture of 16-inch gas line and successively blow torch to piping system in adjacent areas. Vibration analysis nine years earlier judged that the failed line was having excessive vibration and it strengthened the confidence that the hot oil line failed in fatigue dominantly due to hydrogen embrittlement. (Source)
8. Norco Louisiana- US May 5, 1988 (Erosion-Corrosion, Refinery, 4 killed, 20 injured, 4500 evacuated US$ 254,700,000/336,000,000)
An elbow at depropanizer column piping system in a fluid catalytic cracking (FCC) unit failed. A large vapor with estimated 20,000 pounds of C3 hydrocarbon cloud escaped from the failed elbow and ignited in FCC charge heater. The explosion of FCC unit was the most severe damage. A report pointed that the failed elbow suffering excessive locally thinning. The failed elbow was located downstream of the injection point where ammoniated water was added to reduce propanizer condensation or fouling.(Source 1, 2)
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See also: Part 2, Part 3, Part 4, Part 5
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