Tian H.,CNPC Research Institute |
Lu J.,CNPC Research Institute |
Li W.,CNPC Research Institute
International Petroleum Technology Conference [IPTC] (Beijing, China, 3/26-28/2013) Proceedings | Year: 2013
Nearly 800 offshore spill accidents in the U.S. Gulf of Mexico occurred over the past 50 years. Of these, 80% took place in the oilfield development period, 25% during drilling and mining operations, and 72% on the platform or rig. Since 2000, the offshore oil and gas exploration and development has been booming with significantly increased number of oil spills. In 2005, most of leak accidents, including 49 cases with results of leakage of more than 50 barrels and 39 cases of 1-49 barrels, appeared in the history, resulting in total leakage of 16,155 barrels. There is no obviously direct relation among operating water depth, distance from the shore and accident frequency. Most of accidents involved oil spills, followed by diesel and mud spills. The statistics of spill incidents show oil spills accounted for 48% to 63% and the diesel spills for 15% to 21%. There are less accidents resulting in casualties and the Deepwater Horizon accident is the biggest accident in the history. Equipment, weather, human factors and external forces (waves, tides and currents, etc.) are the four major factors behind oil spills at sea.
Li H.,CNPC Research Institute |
Chi Q.,CNPC Research Institute |
Zhang J.,CNPC Research Institute |
Li Y.,CNPC Research Institute |
And 2 more authors.
The Journal of Pipeline Engineering | Year: 2013
Fracture resistance determination was one of the most important aspects during the research and development of the Chinese Second West-East X-80 pipeline steels. More than 30 kinds of longitudinal submerged-arc-welded (LSAW) X-80 pipes were tested using the 2 mm striker Charpy V-notch (CVN) test, the 8 mm striker CVN test, and the instrumented drop-weight tear test (DWTT). It was found that the threshold energy was about 200 J for the 2 mm striker and 8 mm striker CVN tests. Below this threshold, the difference between the 2 mm striker CVN energy and the 8 mm striker CVN energy was small. Above the threshold, however, the difference between the 2 mm striker CVN energy and the 8 mm striker CVN energy increases as the CVN energy increases. It was also found that there is a linear relation between the DWTT energy and the 8 mm striker CVN energy when the latter is lower than 400 J/sq cm. Otherwise, the DWTT energy trends to reach a plateau.