ABS Classes New-Build GSF ‘Constellation I’ Jack-Up

Tuesday, August 05, 2003
Continued frontier development is driving industry's need to refurbish and significantly modify many of the world's 388 active jack-up units for novel projects, improved efficiency and sometimes harsh environments. Frontier development also is spurring the building of new units. Responding to the technical challenges posed by these modifications and the need for new designs, ABS has released a detailed technical Commentary to its Rules for Building and Classing Mobile Offshore Drilling Units (MODUs). The commentary—a further step in providing industry more specific direction on how to apply ABS Rules to these new projects—particularly focuses on jack-ups, which are the predominant type of drilling unit addressed in the Rules for Building and Classing MODUs. ABS provides classification and certification services for 75 percent of the world fleet of MODUs. William J. Sember, ABS vice president Offshore Development, advises that rapid advancements in technology and accelerated frontier development have challenged designers and generated increasing questions with respect to interpretation and applicability of the ABS Rules. "This document serves as a supplement to the MODU Rules. The document also addresses industry questions and is intended to facilitate communications regarding future classification requirements for both modified units and new-builds," said Sember. The commentary addresses some 27 issues, including clarification of load considerations, material selections and structural analysis requirements, and applies to Part 3 of the MODU Rules, which details criteria for the hull and equipment associated with all structures. The Rules include a total of five parts: general introduction; materials and welding; hull and equipment; machinery; and surveys after construction. ABS Principal Engineer Jer-Fang Wu served as project leader for the document. "The commentary addresses a broader range of unit designs and gives owners more detailed guidance on the application of the MODU Rules, particularly those sections applicable to self-elevating jack-up units," said Wu. Bret Montaruli, ABS manager of Offshore Engineering, explains that because ABS Rules need to be applicable to all designs, they are very broad in scope and are often open to interpretation. "The commentary, therefore, addresses designers' questions, such as: 'We know what the Rule says; but when applied to our design, what does it mean?'" said Montaruli. As an example of the clarification provided, Wu says ABS has enhanced the original "Structural Analysis" section to include a discussion on "Analysis of a Primary Structure." "The commentary," advised Wu, "incorporates the following key elements to clarify all analysis-related issues, giving readers the 'background' or 'why' for formulas comprised within the Rule:" 1. Subsection on general concept of the analysis 2. Description of stepping wave through the structure 3. Description of steep waves 4. Loading directions of the waves 5. How to include the P (force)-Delta effect in the analysis 6. Details of the hydrodynamic leg-modeling procedure 7. Consideration of gravity loads and buoyancy 8. Importance of leg buoyancy 9. Clarification of total-elevated load 10. Emphasis of the effects contributed from Spudcan during the analysis 11. Clarification of the wave load effects on a mat-supported unit during analysis "We plan to review and update the commentary periodically to ensure its applicability to current technologies and frontier developments," added Wu.
Maritime Reporter March 2015 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

People & Company News

WOW at USMMA

The United States Merchant Marine Academy Hosts 7th Annual Women on the Water Conference. Last week, The United States Merchant Marine Academy (USMMA) in conjunction with the U.

Methanol Powered Ferry Launched in Baltic Sea

Swedish ferry operator Stena Line has announced that it has converted the Stena Germanica to run on methanol, an industry first.   The company spent $24 million on converting the ship to methanol.

U.S. Oil Train Traffic mostly from Midwest to East Coast

U.S. oil trains delivered more than 13.5 million barrels of crude oil from the Midwest to the East Coast in January, according to government data that gives a first

Offshore

Keppel FELS Delivers 11th Jackup to Mexico

Keppel FELS Limited (Keppel FELS), a wholly owned subsidiary of Keppel Offshore & Marine Ltd (Keppel O&M), has delivered a KFELS B Class jackup rig to Mexican national oil company,

North Sea Oil: Harkand wins Maersk Oil North Sea Deal

Harkand won a multi-million contract with Maersk Oil North Sea Ltd for the provision of DSV services in the North Sea region. The 12-month contract will be serviced by Harkand’s two DSVs,

China's Air Drills Roil South China Sea Waters

China's air force conducted its first drill above the western Pacific Ocean on Monday, the Defence Ministry said, in a move that could exacerbate tensions with

 
 
Maritime Careers / Shipboard Positions Maritime Contracts Navigation Offshore Oil Pipelines Pod Propulsion Port Authority Ship Electronics Sonar Winch
rss | archive | history | articles | privacy | terms and conditions | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.2148 sec (5 req/sec)