Floating Systems

For many field developments, floating structures can play a vital link and can have a large impact on the feasibility and practicality of the project.  Peritus has in-depth knowledge and extensive experience in supporting field development and screening appropriate floating structure selection through to executing sophisticated analysis.

Typically, the floating structures work undertaken by Peritus covers screening, hydrodynamic (motions), stability, structural and mooring analysis and Riser analysis (in conjunction with the Peritus’ dedicated Riser group) across all design engineering phases (including Operate) and can be described broadly by the following activities:

Our services are structured under four broad headings:

• Field Development & Concept Selection through the Appraise and Select Phases, involving Semi-submersible, Deep Draft Floater (Spar), Tension Leg Platform and storage options (FSO, FPSO and FLNG including turret moorings).
• Engineering, Design & Analysis of Floating Structures and their Mooring and Riser Systems (in conjunction with the Peritus’ dedicated Riser group).  Peritus executes these analyses for new builds and conversions.
• Operator Contract Strategy Support and Invitation to Bid (ITB) Documents, Tender evaluation & recommendation through Select and/or Develop Phases.
• Project Management Services, including design supervision, Fabrication, shipyard, integration, commissioning & offshore installation planning and on-site support through Develop and Execute.

Our services are applicable to any company, region, and size of field or water depth.  The scope of our services is different for every client and is based on discussion or preliminary studies to identify requirements. Peritus adds value to its customers in these projects through its combined commercial and technical expertise.

Field Development & Concept Selection

These activities could occur anywhere from the pre-exploration, to post discovery, or even at a brown-field redevelopment stage and include:

• Pre-exploration notional development concept definition and cost estimating and scenario comparison for most floating structures.
• Post discovery concept identification, concept definition, cost estimating, economic analysis and trade-off including a broad multi-disciplinary understanding (subsurface – drilling-facilities-operations-marketing-economics) of the problem.  In the case of Floating Structures, Peritus has great depth in the understanding of strengths and weaknesses and key technical & commercial issues associated with Semi, Spar, TLP and storage options (FSO, FPSO and FLNG) including Contractor capability.
• Full conceptual field development studies including engineering, design, cost estimating and economic valuation.  Peritus also provides full SURF (Subsea, Umbilical, Riser & Flowline) services in addition to floating system engineering and has close association with other engineering parties for the provision of process facilities and fixed platform design & engineering services.
• Full field development FEED services.

Peritus, as a leading provider of specialised services offers the right expertise to undertake and support appropriate independent risk assessment of floating structure designs.  Through their integrated offices, this can be the introduction of new floating structure technologies into new regions (such as FPSO into the GoM or Semi and TLP into Asia Pacific) or and the detailed knowledge of how to address local environmental design criteria) through to the risk assessment of the New Technologies aspects such as FLNG.  For FLNG, Peritus can provide independent expertise identifying the new technology aspects (such as offshore storage and loading) but can also provide a systematic approach to measure maturity and ensure appropriate alternatives are carried till the risk is adequately mitigated.

New Build Projects (FSO, FPSO, FLNG, Semi, Spar and TLP)

Peritus has the capability to screen and analyse floating structures and their associated mooring systems, either as part of early screening or specialized analysis during FEED and Execute.  During the initial evaluation phases, Peritus can undertake preliminary sizing, strength analysis, hydrodynamics (motions) and stability to identify insights appropriate for the environment.  Whether it is challenges associated with floating structures and their associated riser systems (such as Semi or TLP and steel catenary risers in harsh and swell environments) or floating structures in shallower water where mooring and riser systems can be equally challenging.  Activities can include:

• Preliminary sizing of floating structures, their mooring and associated riser system;
• Strength, Hydrodynamics (motions) and stability of floating structures; and
• Interpretation of the environmental conditions and subsea layout in combination with the hydrodynamic results for floating structures, their mooring and riser systems to determine the most appropriate system architecture (hull, riser and potential subsea architecture).

Conversion Projects (FSO, FPSO and Semi)

These activities are typically in support of Operator’s conversion, or re-conversion projects.  Activities would include:

• Survey of either existing assets (e.g. FSO, FPSOs or drilling Semis) as potential conversion candidate vessels.
• Preparation of specifications and scope of work for conversion FSO, FPSO or Production Semi.
• Preparation of shipyard repair, life extension or upgrade technical and engineering packages, as part of the conversion.
• Management of either shipyard affiliated or detailed naval architecture design office for the preliminary and/or detailed design of the vessel. This could either be the supervision of the in-house engineering team associated with one of the major shipyards, or the supervision of a low cost East or South Asian naval architecture design entity.

Validation and Verification Projects

These activities are typically in support of Operator’s new, conversion, or re-conversion projects.  Activities would include:

• Independent analysis of hydrodynamics (motions), mooring, structural and riser analysis including an evaluation of any multi-discipline impact across the system, which can either be managed in-house or employing lower cost analytical centres.
• Third party review of documentation.

Advanced Analysis for Naval Architecture, Marine & Floating Structure Design

Pertius employs subject matter experts across the disciplines that can innovate and solve complex and challenging issues supporting unconventional lower cost project execution.  Capabilities include:

• Naval architecture analysis & design including stability, hydrodynamic (motions), and structural calculations / design for any type of floaters and hulls which can either be managed in-house or employing lower cost analytical centres.
• Mooring system analysis and design for any kind of conventional, spread or single point mooring system.
• Risers system design and analysis for any kind of riser systems or shapes in any water depth whether flexible risers, steel catenary risers, hybrid risers, riser towers, etc.
• Integrated hull / mooring / riser analyses, which typically is an issue when providers for the vessel and mooring on the one hand and the risers on the other hand are contracted separately.

Operator Contract Strategy Support and Invitation to Bid (ITB) Documents

For operators, the selection of the contract strategy and the tender preparation and management is actually the most critical activity towards a successful Floating Structure development.  These activities are in support of Operators’ projects; Peritus can develop such strategies (including framing workshops) or support the Operator in assessing and selecting an appropriate contract strategy for the development. 

Peritus Floating Structures Staff have experience developing the following contract strategies and as well as developing these for the Operator can provide valuable lessons learned:

• Leased or Purchased Storage Solutions (FSO and FPSO), including allowing market dynamics to support the decision;
• Floating Asset (FPSO, FLNG, Spar, Semi or TLP) Sole source through to Delivery Competition, either at a screening level (through Select) or through the early phases of Develop (FEED) across the international market, to deliver the most technically and commercially attractive solution;

As part of developing the contract strategy, or once already developed by the Operator, Peritus can develop the technical package including scope and specifications to support the Invitation to Bid.  Activities include:

• Preparation of Detailed Scope(s) of Work;
• Preparation of either detailed or functional specifications;
• Support to commercial documents for both project and operations phases, compensation & incentive schemes, and key contractual requirements & terms for purchases or leases.
• Management or participation in tender processes for the lease or purchase of FPSO, FSO, MOPU & FLNG units including managing of tender phase negotiations, tender analysis, formal recommendations and support of typical operator internal approval processes.

The primary External analysis tools used by PERITUS are:

• Hydrostar
• Orcaflex
• Orcalay
• Mathcad
• MCS Pipelay
• Solidworks
• Abaqus
• Ansys

In addition to discipline engineering roles, Peritus can and has provided Project Management Services in the form of provision of senior staff to owners engineering roles; supervising the design contractors during Develop and Execute.

These activities can either be in an execution mode, typically in support of contractors or Operator.  Activities would include:

• Provision of fabrication yard and shipyard personnel for the fabrication, construction, conversion, life extension, upgrade, integration and pre-commissioning of new or converted FPSOs.
• Provision of offshore personnel for the management of offshore installation and FPSO commissioning personnel.