07121-1401

Goal
This project will design a composite riser system which allows ultra-deepwater and high-pressure well capability using currently available industry standard tensioning capabilities, and construct full-diameter, sub-length specimens for comprehensive lab testing. The system must satisfy regulatory concerns, meet industry performance standards, and provide sufficient margins of safety to eliminate apprehension at the operator level. The result of this project will be a design solution that is ready for trial/use in the field with proven top-side tension leg platform (TLP) and seagoing platform for acoustic research (SPAR) applications under similar load conditions at water depths far exceeding current capabilities.

Performers
Lincoln Composites, Lincoln, NE 68524
Stress Engineering Services, Houston, TX 77041

Background
Carbon fiber composite riser construction has long been recognized as having the potential to greatly reduce the weight of marine riser systems. However, before composite risers will be accepted for use in drilling applications, the issues of wear and abrasion of the riser bore must be addressed. Sliding contact occurs between the rotating drill string and the bore of the riser, and cuttings transported in drilling fluids from the well bore can impinge against the riser bore. Drilling activity can therefore result in abrasion erosion, tearing, and/or gouging of the relatively soft elastomers and thermoplastics typically used for lining composite risers.

Lincoln Composites will utilize previous experience in the hybrid riser field, state of the art finite element modeling software for hybrid composite structures, as well as collaboration with industry experts in large scale design and testing methods, to carry out this design project. Deliverables will include technical reports and presentations and a final report detailing all of the project results.

Potential Impacts
A hybrid composite riser that can safely perform all of the required functions of a drilling riser operation could be capable of more than a 50% reduction in riser weight compared to all steel risers. The weight reduction of a hybrid composite/steel riser system would enable access to ultra-deepwater high-pressure reservoirs that would otherwise prove to be cost prohibitive or technically impossible using conventional all steel means.

Accomplishments
During technical planning meetings, it was determined that the maximum expected temperature will be no greater than 180F, an O.D. (with buoyancy) based on a 60 inch rotary will be used, and that a 19.5” drift diameter riser design will be used for the project since it gives the operators maximum flexibility. Line pipe has also been located for the project—API5L, X80, PSL2, DSAW (2) pieces at 40’ in length with 22” O.D. x 1” wall thickness.

The Global Riser Analysis was completed and the results were presented at the TAC2 meeting in June 2009. The completed report will document the functional performance requirements of the drilling/completion riser as developed by industry participants, selection of a cost effective wrapping method/manufacturing process with a process flow that addresses future manufacturability of large volume production, and a comparative cost benefit analysis – including autofrettage pre-stressing vs. minimal tension required to effectively wrap, plus an effective end termination manufacturing/fabrication process.

The Basis of Design Document was also completed and submitted for review in June 2009. Following the completion of this document, a Preliminary Design Review was conducted in August and a more comprehensive design review in November 2009.

Current Status
Project Management. Work continues on key project management activities. A Project Management Plan is maintained to include a current work breakdown structure that concisely addresses the objectives and approach for each task with all major milestones and decision points. Biweekly teleconferences are held to apprise the project team of progress and current issues. Monthly progress reports are submitted. Presentation materials and minutes from all reviews and meetings are made available to all participants through postings to the RPSEA SharePoint site.

Composite Riser Design, Analysis and Prototype Fabrication. Lincoln Composites has designed and initiated fabrication of short length full diameter riser joint test specimens for concept qualification testing. Activities will include a summary design analysis report documenting a general discussion of load sharing structure design, a model evaluation of the expected load share between the Structural Composite Overwrap (SCO) and the steel liner, and a complete end termination and joint interface design intended for test purposes. Additional activities will include definition and implementation of a fabrication Quality Assurance/Quality Control (QA/QC) process in compliance with industry practices and the performance of a Health, Safety, and Environmental (HS&E) evaluation of the riser fabrication processes. The evaluation will be extended to the in-service (field) use of the light weight riser system.

Qualification of Riser Design. Lincoln Composites will define and then perform appropriate specimen testing to qualify the hybrid riser design methodology. This will include verification of the end termination/interface design with the analyzed results of specimen burst tests and specimen testing and analysis to determine riser sensitivity to handling, storage, and impact energy. This work will be extended to produce a recommended transportation and handling procedure for the riser system components. Other elements of the task will include identification of any special features or procedures to minimize riser degradation during storage, transportation, handling, and field use and qualification through design, fabrication, and laboratory testing of specimens that the concept will meet the functional performance requirements. Lincoln Composites will use the design methodology and information developed within this project to prepare a riser design for a Phase 2 Base Case Test field location. This information will also be used to estimate a complete riser system cost and fabrication schedule.

Project Start: December 5, 2008
Project End: October 31, 2010

DOE Contribution: $1,678,411
Performer Contribution: $1,030,574

Contact Information:
RPSEA – Jim Chitwood (jchitwood@rpsea.org or 713-372-2820)
NETL - Jay Jikich (Sinisha.Jikich@netl.doe.gov or 304-285-4320)
Performer Company – Donald Baldwin (dbaldwin@lincolncomposites.com or 402-470-5017)

Additional Information:

Final Project Report [PDF-19.8MB]