As the oil & gas industry ventures into deeper waters and more extreme environments, operators, umbilical equipment designers and manufacturers, and installation companies, have been working together to ensure umbilical installation is as smooth an operation as possible. Pat Oakley reports.
Umbilicals form a critical link in the recovery of hydrocarbons involving subsea production. Over the past 30 years, many umbilical systems have been installed in waters ranging from a few meters to depths exceeding 2000m. Installing umbilical products subsea presents several challenges and it is understandable that some diffi culties have been encountered during past operations.
With the trend to ever deeper waters and longer tie-back distances, and with subsea production moving into increasingly hostile environments, it is likely that installation will continue to be a problem for the industry. In 2009, the Umbilical Manufacturer’s Federation (UMF), in conjunction with the Society for Underwater Technology (SUT), arranged a one-day seminar/workshop with the objective of gaining a better appreciation of the issues.
With this, the UMF aimed to develop a strategy with the ultimate goal of reducing the occurrences of umbilical installation problems.
The workshop adopted a similar format to that used for the UMF umbilical blockages initiative which was very successful and resulted in a joint industry project addressing blockage avoidance in subsea productions systems (www.basics-jip.com).
The workshop was a great success, with more than 100 attendees from operators, installation companies, equipment designers and manufacturers. Morning presentations highlighted a number of significant issues in relation to umbilical installation. In the afternoon, the audience was organized into groups, each to discuss a topic arising out of the morning session. The major themes were :
- Reducing the size of subsea terminations.
- Matching vessel spreads to umbilical needs.
- Better understanding of umbilical internal behavior.
- Standards and specifications.
- Lessons learned.
- Training and awareness.
Various suggestions to improve installation activities arose from the different discussion groups including:
- Address the issue of termination size and weight by designing smaller units, relocate distribution onto subsea structures, change handling/deployment methodologies, or combinations of such actions.
- Develop best and recommended practice documents.
- Assess and revise the current standards and specifications.
- Standardize terminology throughout the industry.
- Standardize information presentation throughout the parties involved.
- Encourage development of an ‘umbilicals network’ that involves the entire supply chain from an early stage of a project.
- Develop a global ‘lessons learned’ database.
- Develop training modules to educate design and installation personnel.
- Survey/review current installation spreads to identify any shortcomings with a view to developing a specification for spreads for umbilical installation purposes.
The workshop closed with strong feedback from attendees that the issues highlighted should be followed up. As a result, the UMF undertook to raise the output from the seminar with a number of major installation companies. A meeting took place with installation contractors in early 2010. The various themes raised at the previous workshop were tabled and discussed.
A considerable amount of time was spent on the subject of umbilical terminations, this being one of the major concerns of installation companies.
The general view was that terminations were too large and heavy, quite often not cylindrical, and lacked sufficient handling points. The size and weight caused problems when loading onto a vessel, and even more so when over-boarding during the installation process. This often led to increased installation time and subsequent significant weather downtime.
These factors were compounded by the fact that many installation vessels are not purpose-designed for umbilical installation and the termination handling requirements proved difficult to meet with normal crane outfitting.
Other issues relating to the design of umbilical terminations were raised. It was noted that design premises rarely address size and weight limitations, and that the design for the same number of elements varies with designer.
The meeting participants observed that dealing with the issue of large terminations would require involvement by all parties, including clients, FEED contractors, control system designers, and termination designers.
It was proposed that a way forward for dealing with the issue would be a JIP drawing in all interested parties.
As a result, OTM Consulting – a company with a solid track record of successful JIP launch and management – was engaged to map industry interest in a termination JIP. Interest was strong and a JIP launch meeting took place in Aberdeen in April 2011, at which several companies confirmed their willingness to participate. As a result, the first Umbilical Termination Size Reduction JIP (UMSIRE) meeting took place in September 2011.
To date, UMSIRE has 16 member companies encompassing operators, installers, equipment designers and manufacturers.
UMSIRE membership aims to collaboratively develop a best practice document addressing the need to optimize the shape of umbilical termination assemblies (UTAs) and identify guidelines for their size and weight, thus allowing:
- Planning and consideration of installation issues at the design stage of the umbilical system resulting in UTAs to be more proportional to the umbilical size and the installation equipment capabilities.
- Evaluation of the economic and operational risks during the design phase.
- Estimation at the design stage of the final UTA size on the basis of the number of functionalities of the umbilical system
One year after its official launch, the JIP is well on track with the preparation of its deliverables which will clearly serve to address one of the main concerns raised by installers (further information on the UMSIRE JIP is available at www.umsire.com).
The UMF reports that further initiatives are under consideration to address a number of the other themes and issues raised at the original installation workshop. OE
The Umbilical Manufacturer’s Federation
The UMF is a group of global umbilical manufacturers, founded in 2001, with the principal objectives of improving umbilical safety, reliability and standards. The UMF seeks to support the subsea oil & gas industry by various activities including umbilical related workshops, guidance notes, and joint industry projects. The UMF comprises Aker Solutions, Duco, JDR Cable Systems, Nexans, Oceaneering Umbilical Solutions and Parker Scanrope, who between them account for the majority of umbilical systems installed in subsea production systems.