Offshore Drilling Rig Generations

April 13, 2015

A qualified Texas or Louisiana offshore injury attorney handling a maritime personal injury lawsuit will be mindful of the technological capability of the vessel involved. Semisubmersible offshore drilling rigs are often categorized by “generation.” A drilling unit’s generation is based on when it was built or upgraded, its maximum operating water depth, and its drilling capability. Your Texas offshore injury lawyer should know the generation of the drilling vessel involved in your accident. Basic information regarding offshore drilling rig generation is as follows:

  1. First Generation. Built in the 1960s, these rigs can drill (operating) in 800 feet of water or less. Designers include Shell Oil, ODECO, Friede & Goldman, Neptune, Earl & Wright, and Aker Mek Verksted. First-generation rigs use mooring (anchors) to stay in place or “keep station.”
  2. Second generation. Built in the 1970s, it can drill in 1,000-1,500 feet of water. These include the Aker H3 design, of which 37 were built, and many were ultimately upgraded to third-generation rigs. Second-generation rigs rely on mooring for station keeping. As many as 60 of these vessels are still in operation today.
  3. Third generation. Built in the early 1980s, it can operate in 2,500-3,000 feet of water. Many were intended to operate in relatively harsh weather conditions, including in the middle-depth Gulf of Mexico and the North Sea.
  4. Fourth generation. Built or upgraded in the late 1980s, it can drill in 3,000-7,500 feet of water. In 1985, Reading & Bates completed the Jack Bates, which set the standard for fourth-generation offshore drilling rigs with its high variable deck load (VDL) capacity, reduced ocean motions, advanced drilling system, and the capability to drill in 7,500 feet of water. Fourth-generation rigs include moored rig designs and those that keep stations with “dynamic positioning” (DP), which means thrusters and GPS/satellite systems are utilized to keep the vessels on location. Fourth-generation rigs include upgraded designs like Noble’s EVA-4000s and new designs such as the Aker H-4.2DP. As many as 40 fourth-generation rigs are still in operation.
  5. Fifth generation. Built in the late 1990s and early 2000s, these are the first “ultra-deepwater” offshore drilling rigs capable of drilling at 7,500-10,000 feet. They have several automated and computer-controlled systems, including drill floor equipment, DP station-keeping systems, power management, blowout preventers (BOPs), and pipe handling systems. Many of these rigs have DP systems certified to DP-3, which means they are theoretically “triple redundant” to avoid drift-offs. One of the first fifth-generation designs presented was the RBS 10,000, which has high-specification outputs, including the ability to drill to 10,000 feet, a 10,000-ton deck load capacity, a large open deck area, and further reduced motions. Fifth-generation rigs were built during lean economic times, and less than 25 are in operation today.
  6. Sixth Generation. Built in the mid-2000s, sixth-generation rigs can drill in 10,000 feet or more of water and have modular top drive systems. Some “dual activity” sixth-generation rigs have more than one drilling derrick. Examples of sixth-generation offshore rigs include the ENSCO 8500 rigs, the Noble Jim Day, and the Noble Danny Adkins. There are around 70 in operation.
  7. Seventh Generation. Some newer rigs with dual BOPs and higher variable deck loads have been dubbed “seventh generation.”

If you or a loved one has suffered a serious injury while working off the shores of Texas or Louisiana, consult with a qualified Houston offshore injury lawyer for a free, confidential consultation. The reason is that most offshore drillers, oil companies, and oilfield services companies are based in Houston, and qualified Houston injury lawyers will know where and how to pursue your claim. The Houston offshore injury lawyers at Morrow & Sheppard can help. They have membership in the prestigious Maritime Law Association. They have assisted clients in various maritime injury cases involving accidents throughout the Gulf of Mexico.

Get a Free Case Review by Calling Morrow & Sheppard Now.

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