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BS has enhanced an existing set of subsea guidelines
to create two new technology-specific guides that will facilitate
coordination and communication among designers, operators, |
contractors and subcontractors. The Guide for Building and Classing
Subsea Pipeline Systems and Risers (2001) is now revised and
published as two stand-alone texts: the Guide
for Building and Classing Subsea Pipeline Systems
and the Guide
for Building and Classing Subsea Riser Systems (March
2004).
The new subsea guides help operators adopt a classification society
point of view to identify where risers end and where pipelines start,
as well as assist with the development, design, construction and
operation of subsea pipeline and riser systems.
“ABS is responding to evolving technical developments and
logistics of offshore construction by dividing the existing
Guide into two new carefully compartmentalized guides that
are still coordinated with the big picture,” said Ernesto
Valenzuela, ABS Offshore Technology Manager.
The general requirements of the previous guide were not necessarily
applicable to the specific worldwide environments involving risers
and/or pipelines. Both new guides now have been rewritten for worldwide
application. The satisfaction of individual requirements may vary,
especially for projects located in frontier areas, such as those
characterized by great water depth or areas with little or no previous
operating experience. Many provisions of the individual guides often
can be satisfied merely on a comparative basis of local conditions
or past successful surveying practices, Valenzuela advises.
“ABS acknowledges that a wide latitude exists as to the extent
and type of documentation required to satisfy the provisions of
these guides. Appendices to the guides allow for innovation because
the methods of design and construction are constantly evolving,”
he said.
For example, the guides provide analytical methods and procedures
for vortex-induced vibration (VIV) of free-spanning pipes and catenary
risers which offer new industry-enhanced formulas. In addition,
detailed specifications for hydrostatic pressure tests and unified
inspection requirements will assist operators with the implementation
and management of subsea integrity programs.
The Subsea Pipeline Systems guide details specific pipeline
material and design issues in terms of existing methodologies and
safety factors, including:
- Piping components and pipe coating
- Welding of pipes and components
- Corrosion control
- Flow assurance analysis
- Pipeline rectification and intervention
- Routing
- Pipe-in-pipe design
- Pipeline bundle design
The Subsea Riser Systems guide details criteria for metallic
and catenary risers reflecting the current state of deepwater practice
in offshore riser design:
- Global response analysis and riser components design
- Materials and welding
- Riser components and pipe coating
- Extension of use
- Steel catenary risers (SCR)
- Pipe-in-pipe SCR
Both guides outline the general scope and conditions of classification
and as well as material and design issues shared by both technologies:
- Environmental effects
- Strength and stability criteria
- Installation, construction and testing
- Corrosion control
ABS publication #64,
Guide for Building and Classing Subsea Pipeline Systems
and ABS publication #123, Guide
for Building and Classing Subsea Riser Systems are
available for free download.
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