DnV SERVIng THE EnERgy InDUSTRy managing deep and ultra-deepwater technology
services from the sea surface to the reservoir
The power To eXpand inTo deeper waTer
02 I energy I managing deep and ultra-deepwater industry I
DNV main non-classification services within deepwater technology Verification/certification SHE risk management Technology qualification (TQ)
Asset risk management (ARM) Enterprise risk management (ERM)
I managing deep and ultra-deepwater industry I EnERgy I 03
coNteNts 04 06 08 10
The global picture On the sea surface From the sea surface to the seabed On and below the seabed
12 Drilling and wells 13 Materials and DnV offshore codes 14 Main services
The era of ‘easy oil’ is over. Operators are moving into more remote and deepwater areas to explore and produce oil and gas. DnV has been involved with offshore technology over the last 40 years and serviced the operators and contractors into deep and ultra-deep waters. This brochure presents some of DnV experiences and services within the field of deepwater technology.
©istock
The power To eXpand inTo deeper waTer
04 I energy I managing deep and ultra-deepwater industry I
The Global picture
I managing deep and ultra-deepwater industry I energy I 05
Verification and Certification We ensure your projects are properly managed through transparent risk based verification and certification. SHE Risk Management We develop, implement, maintain and continuously improve the best practices in SHE management. Technology Qualification We provide you with the confidence that your technology will function reliably. Asset Risk Management We safeguard integrity and maintain optimal production safely and cost-efficiently. Enterprise Risk Management We provide a complete view of your organisations total risk exposure and manage these risks in an integrated way.
ŠDet Norske Veritas
Typical water depth definitions: Shallow water: 0 – 150 m Deep water: 150 – 1500 m Ultra deep water: beyond 1500 m
06 I energy I managing deep and ultra-deepwater industry I
on the sea Surface Metocean Adequate modelling of environmental conditions is vital when assessing the integrity of offshore structures. Uncertainties in wave, wind and current conditions govern the applied loads and may well be more important than the corresponding uncertainties in the capacity of an offshore structure. The modelling of waves, wind and current has been an important part of DNV services for several decades. Some important projects in the past have been “Ocean Research Design Criteria” for Conoco, “Norwegian Ocean Current Data Analysis Project (NOCDAP)” for Exxon, and verification of the wave conditions at Ekofisk for Phillips. In Fig. 1 a typical Hs/Tp contour plot is shown. DNV has extensive project experience in analysis of measured data and hindcast data for specific locations. Independent analysis and verification of environmental design bases have been performed for several areas.
Hydrodynamics When dealing with deepwater technology the floater is an integral part of a dynamic system that includes the mooring, tendons, risers, umbilicals, and other fluid transfer lines connected to the floater via other nearby structures/floaters. A hydrodynamic analysis is usually the starting effort, either as a simple frequency domain analysis, or a more advanced, time domain, coupled analysis.
For generation of hydrodynamic models the DNV Software suite of programs are utilised and models may include: Traditional WADAM panel model of a floater with focus on 1. order wave frequent and 2. order drift forces (difference frequency). Panel (1/4) model of a TLP with associated surface mesh for analysis of 2. order sumfrequency forces (springing). See Fig.2. Panel model with surface mesh for time-domain analysis using WASIM with consistent treatment/analysis of hydrostatics during a wave cycle. Relevant DNV codes: DNV-RP-C205, Environmental Conditions and Environmental Loads. DNV-RP-F205, Global Performance Analysis of Deepwater Floating Structures. DNV-OS-F201 Dynamic Risers.
Global Performance The slender structures and the floater comprise an integrated dynamic system. This implies that the slender structures influence the floater motions, and the floater motions influence the response in the slender structures. The motion response characteristics of a floater is usually described by three components: The mean offset which is governed by the mean environmental loading due to wind, waves and current and the total system restoring characteristics.
The low frequency (LF) response is due to dynamic excitation from wind and wave drift forces. The wave frequency (WF) loading due to 1. order wave forces. Examples of global performance analyses: Coupled analysis model of a GoM Truss Spar with, mooring lines, top tensioned risers (TTRs) and steel catenary risers (SCRs). The TTRs are simulated with advanced stick/slip modelling. See Fig.3. Multibody simulations of a FPSO with mooring lines and SCRs and transfer lines over to a TLP with TTRs and tendons. This could be simulated with, or without hydrodynamic interaction. More peculiar TLP responses like ringing and springing are usually denoted high frequency (HF) responses. These HF responses requires special type of higher order analyses. Relevant DNV code: DNV-RP-F205, Global Performance Analysis of Deepwater Floating Structures.
Marine operations DNV has over 30 years experience in delivering verification work and warranty approval to the offshore industry. History tells that major offshore accidents occur due to the fact that certain areas have not received proper attention. The verification carried out has been satisfactory, but undefined grey areas between the different parties
ŠDet Norske Veritas
I managing deep and ultra-deepwater industry I energy I 07
involved have not been handled satisfactorily, or in many cases, at all. This emphasises the importance of continuity between the different stages of design, construction, installation and in-service operation and calls for an integrated approach, not fragmented verification carried out by different bodies. DNV provides independent assessments, verification, or approval Fig.1
Fig.2
services for complete operations, or elements thereof. Example in Fig. 4 shows a template installation where independent CFD simulations (1/2 model) have been performed using the software COMFLOW.
DNV-RP-H101 Risk Management in Marine and Subsea Operations DNV-RP-H102 Marine Operations during Removal of Offshore Installations DNV-RP-H103 Modelling and Analysis of Marine Operations.
Relevant DNV codes: DNV Rules for Planning and Execution of Marine Operations Fig.3
Fig.4
08 I energy I managing deep and ultra-deepwater industry I
From the sea surface to the seabed mooring systems Within DNV, the typical mooring services comprise classification, certification, verification, testing, execution of JIPs, research on mooring materials and components as well as consultancy services and independent analyses. Fig.1 shows testing of a fiber rope for a GoM installation. Classification of mooring systems mainly according to DNV’s own standard, or other internationally recognised standards. Mooring analysis calculations may comprise: line tensions under extreme conditions analysis of marine operations fatigue calculations structural reliability calculations dimensioning and material selection. Relevant DNV codes: DNV-OS-E301, Position Mooring DNV-OS-E302, Offshore Mooring Chain DNV-OS-E303, Offshore Mooring Fibre Ropes DNV-OS-E304, Offshore Mooring Steel Wire Ropes DNV-RP-E304, Damage Assessment of Fibre Ropes for Offshore Mooring.
services are mainly focused on verification, certification and consultancy services. Design of dynamic riser systems rely heavily on being able to analyse these systems and DNV is regarded as being at the forefront of this. Our key software for these type of analyses are DeepC, which include the Marintek developed software RIFLEX and SIMO. Project examples shown comprise: Inspection of flexible risers and umbilicals hung off from a semi submersible in the North Sea. See Fig.2. Riser and umbilical interference. See Fig.3. Relevant DNV codes: DNV-OSS-302, Offshore Riser Systems DNV-OS-F201, Dynamic Risers DNV-RP-F201, Design of Titanium Risers DNV-RP-F202, Composite Risers DNV-RP-F203, Riser Interference DNV-RP-F204, Riser Fatigue DNV-RP-F206, Riser Integrity Management. Fatigue is usually one of the critical failure modes for dynamic riser systems and for SCRs the critical areas are hang off and touch down (TD). DNV has put a lot of effort into refined analyses of these high stress areas.
Riser Systems Services related to metallic as well as flexible risers are part of DNV’s core services and are provided at all our major offices around the world. The
For riser systems the knowledge and experience management throughout the life cycle is crucial to ensure risers are:
managed cost effectively and safely, reliable and available, and that due focus is given to personnel, assets, operations and the environment.
Umbilicals Over the last decade DNV has been heavily involved with umbilicals. Our services and involvements have evolved from traditional verification and certification services to advanced analyses of this special type of product. Umbilicals are considered a highly multidiscipline type of product requiring a complex risk/reliability assessment (e.g. need for redundant functional lines). Usually there will be tailor made solutions with novel aspects involved and it can be argued that there is a general lack of industry accepted acceptance criteria (e.g applicable SN curves, or other material qualifications). Umbilicals are light-weight structures and hence often challenges global design/analysis as well as stress calculations (fatigue analyses). The figures 4 and 5 shows: Typical umbilical cross-sectional design. Analytical model for fatigue stress calculation in helix elements using the DNV software HELICA.
ŠNexans
I managing deep and ultra-deepwater industry I energy I 09
Fig.4 Fig.1
Fig.2
Fig.3
Fig.5
10 I energy I managing deep and ultra-deepwater industry I
on and below the Seabed Subsea structures and systems DNV performs technology qualification, quality surveillance, verification, technical risk management, in-service and failure investigation services for subsea systems and components, such as: x-mas trees and wellhead systems manifold systems with supporting and protective structures PLETS, PLEMS, jumpers, and piles tie in and connection systems pipeline and flowline repair systems subsea boosting and subsea separation systems systems for prevention of corrosion, hydrate and wax formation. Concept design/engineering/ modelling: RISK (from identification to management) installation and operation procedures and pitfalls wicked problems concept engineering benchmarking/best practices/joint industry projects evaluation of alternatives gap analysis documentation. Package solutions: concept design/high-end analysis system evaluation specifications SIT/FAT HAZOP/HAZID installation spare part philosophy integrity management
operating manuals and system-wide procedures. Relevant DNV codes: DNV-OSS-306 Verfification of Subsea Facilities DNV-RP-C204 Design against Accidental Loads DNV-RP-F112 Design of Duplex Stainless Steel Subsea Equipment Exposed to Cathodic Protection DNV-RP-F301 Subsea Separator Structural Design DNV-RP-F302 Selection and Use of Subsea Leak Detection Systems DNV-RP-O401 Safety and Reliability of Subsea Systems DNV-RP-O501 Erosive Wear in Piping Systems.
Geotechnical DNV foundations take the structures down to the ground. See Fig.1, providing an overview of services. Our services involves soil interpretations and soil structure interaction analyses mainly within anchors, subsea structures, pipelines, jackets, jack-ups, GBS, wind turbines, and ports and terminals. Our services are related to classification, verification and consultancy. Relevant tools: PLAXIS 2D and 3D Flac2D and Flac3D ABAQUS SPLICE SHAKE GRLWEAP DIGIN (fluke anchors) IMPACT, LACSAC, ROTSTAB
DROPIN (Torpedo piles). Relevant DNV codes: DNV RP-E301 Design and Installation of Fluke Anchors in Clay DNV RP-E302 Design and Installation of Plate Anchors in Clay DNV Classification Notes 30.4 “Foundations” DNV-OS-C101 Design of offshore steel structures DNV-OS-E301 Position Mooring DNV-OS-F101 Submarine Pipeline Systems.
Pipelines A pipeline system is a significant financial investment and forms a key element of the oil and gas value chain. The vast number of both planned and installed pipelines puts increasing focus on asset integrity management and life extension. From well to shore, concept to operation, internal flow to external threat, ensuring that each pipeline is designed, fabricated and operated in a safe, reliable and costeffective manner involves many professional disciplines. DNV offers the full range of services for all phases of offshore pipeline systems – such as design, manufacturing, installation, testing, operation and abandonment services. See Fig.2. For our customers, DNV has developed new pipeline training programmes covering all aspects of pipeline technology from concept to operation. DNV’s first submarine pipeline code was issued in 1976. Since then, DNV,
©FMC Kongsberg/Statoil
I managing deep and ultra-deepwater industry I Energy I 11
together with the pipeline industry, have created a series of internationally recognised standards and recommended practices. Relevant DNV codes: OSS-301–Certification and Verification of Pipelines OSS-313–Pipe Mill and Coating Yard Qualification OS-F101–Submarine Pipeline Systems RP-F101–Corroded Pipelines RP-F102–Pipeline Field Joint Coating and Field Repair of Linepipe RP-F103–Cathodic Protection of Submarine Pipelines by Galvanic Anodes RP-F105–Free Spanning Pipelines RP-F106–Factory Pipeline External
Pipeline Coatings for Corrosion Control RP-F107–Risk Assessment of Pipeline Protection RP-F108 – Fracture Control of Pipeline Installation Methods Introducing Cyclic Plastic Strain RP-F109–On Bottom Stability design of submarine Pipelines Fig.1
RP-F110–Global Buckling of Submarine Pipelines Structural design due to HPHT RP-F113–Pipeline Subsea Repair RP-F116–Integrity Management of Submarine Pipeline Systems RP-F118–Pipe Girth Weld AUT Qualification.
Fig.2
12 I energy I managing deep and ultra-deepwater industry I
Drilling and wells
Drilling and wells DNV is offering services towards the development of drilling and well systems. These services includes verification of drilling systems, recertification of BOPs and well control systems, qualification of new technologies for drilling and wells and also by performing reliability studies and concept evaluations of well completion systems, smart well solutions and subsea systems.
Structural well integrity DNV is presently running a joint indus-
try project (JIP) to develop improved methodology for wellhead fatigue calculations, ultimate and accidental structural capacity and integrity management. We also perform structural analysis of wellhead systems and dynamic analysis of riser tension systems. Fig. 1 and 2 shows a typical analytical model of a riser system with tensioner/floater interface and global and local soil structure interaction (SSI) models.
Fig.1
Fig.2
I managing deep and ultra-deepwater industry I energy I 13
Materials and offshore codes DNV Service Descriptions
Offshore Service Specification (OSS)
Offshore Standards (OS) Classif
DNV Offshore Standards
ication
Object
and sp
ecial fa
System
s and
Supporting documents
Materi
als an
DNV notes
DN recom V men practic ded es
cilities
RPs struct
ures
d com
ponen
Non D
ts
Operation Design construction and assembly
NV do
cume
nts
Supply of materials, components and equipment
Severe safety, environmental and financial consequences of potential equipment failure in deep water production require assuring the mechanical integrity of the subsea system during the entire life cycle.
fore requires not only innovation in materials design, but also deeper insight into the limitations of existing ones. This will allow the industry to cost-effectively and safely design, manufacture and operate better systems.
Materials degradation in service is a constant threat in all operating systems, but poses major challenges in deep water production due to the harsh physical environment that may be present, as well as difficulty of accessing deep water components for inspection, repair or replacement. Carbon steel is still the first material of choice, due to its availability, good weldability and low cost, but in some cases corrosion resistant alloys are required to prevent materials degradation.
Corrosion can be controlled through design, materials selection, application of coatings and claddings, and cathodic protection. Ongoing monitoring and maintenance also help to maintain system integrity throughout the intended design life.
DNV standards and recommended practices
With a broad and deep competence in materials and corrosion technology and testing, DNV is well positioned to help the energy industry in addressing these challenges. We provide services such as corrosion control consultancy, materials selection, verification, qualification of new technology, laboratory testing, failure investigation and fabrication follow-up.
Over the last 40 years DNV has issued rules and standards for the offshore industry. The three level hierarchy provides a flexible and user friendly menu covering services (OSS), technical standard (OS) and recommended practices (RP). Over the years this system has been expanded to cover the key disciplines and all phases, and also provides reference to other, internationally accepted standards.
This creates a variety of problems, since existing materials may not be adequate for new applications and systems. Stretching the design envelope there-
Laboratories are an important part of the technology base at DNV and are fully integrated with our entire range of technical disciplines. We have full scale corrosion testing facilities to verify that materials, corrosion inhibitors and coatings meet defined requirements. We take a collaborative approach to both science and engineering, in order to develop the best solutions for the client.
14 I energy I managing deep and ultra-deepwater industry I
Main Services Verification and Certification Verification are activities aiming at satisfying the expectations or requirements of owners, authorities and other stakeholders in terms of safety, environmental protection and functionality. Verification is an examination to confirm that an activity, a product or a service is in accordance with specified requirements. Certification is a confirmation through the provision of objective evidence that specified requirements have been fulfilled. Scope is defined by DNV, or an authority. The SoW for verification is ultimately decided by the customer, while the scope of work for certification is decided by DNV (or the national authorities when we issue certificates on their behalf). Certification is documented with a Certificate. Verification is documented by a report, or a statement of compliance, not a certificate. For certification the work is always carried out by an independent third party. The verification services offered by DNV shall be risk based, transparent and recognised as best industry practice. See Fig. 1.
SHE services Dropped objects Dropped objects risk assessments uses analytical techniques to quantify the risk associated with dropped objects on subsea structures. The analysis calcu-
lates dropped object frequencies and impact energies based on topsides lifting requirements to assess the need for structural protection or relocation of subsea equipment and pipelines. DNV-RP-F107 Risk Assessment of Pipeline Protection. DNV proprietary software (DORA) applies the methodology defined in RP F107.
Subsea release and dispersion Modelling analytical methods to assess the impact of subsea releases on topsides infrastructure with respect to loss of buoyancy, ignition of gas clouds and potential pool fires on the sea surface. Quantitative techniques for modelling subsea releases, their subsequent dispersion and consequential impact to topsides facilities. Techniques include modelling of subsea release rates (DNV Piperup software), quantification of dispersion and surface bubble zone (DNV Plumerise software) and above surface dispersion/consequence assessments (DNV PHAST software and CFD tools).
Performance forecasting/intervention assessment Reliability, availability and maintainability (RAM) assessments are used to predict the performance expected from a deepwater development to find the trade-off between production availability and corresponding costs. Tailor made solutions using the DNV proprietary MAROS simulator, are widely used in the industry. DNV extends the traditional RAM assessment to include logistics associated with subsea interventions. This allows infrastructure investment decisions to be based
on through life cycle cost, not just CAPEX. See Fig. 2.
Technology qualification Ten years ago DNV issued a procedure for qualification of new technology. Over these years many projects have been executed with basis in the TQ process described in DNV-RP-A203 and many clients have adopted this structured process for qualifying new technology. See Fig. 3.
Qualification is the process of providing the evidence that the technology will function within specific limits with an acceptable level of confidence. DNV TQ definition
Some of the benefits include: improved end users’ confidence in the system optimised qualification testing and analysis interface between manufacturers and sub-vendors uncovered reduced risk cost during operation by reducing uncertainties and increasing the reliability
Fig.1
I managing deep and ultra-deepwater industry I energy I 15
a standardised qualification process. Examples of TQ participation by DNV include: subsea processing, compression, boosting pipeline applications: direct electric heating, dual director wye, cryogenic pipe-in-pipe, etc. subsea equipment: MPFM, wet and dry mate connectors, pumps, power umbilicals, etc. dry tree semi concepts. Relevant DNV codes: DNV-OSS-401 Technology Qualification Management DNV-RP-A203 Qualification Procedures for New Technology.
Fig.2
Asset Risk Management ARM is about helping organisations to safely and responsibly obtain maximum value from facilities, equipment and people without compromising safety or the environment. Business unit managers and asset managers constantly have to identify new opportunities that better control operational results and associated risks. Those assets that succeed in operating more efficiently and reliably than their competitors will be positioned to ensure long-term success. DNV has developed a range of solutions to help anticipate and manage these challenges. The approach selected by DNV is to work closely with our customers to understand the unique characteristics of their operations and develop the best solutions for their assets. Our services range from assessment and benchmarking through management and implementation to advanced materials technology investigations. Typical solutions brought to the market are assessment and benchmarking, asset operation management, production optimisation, maintenance and
Fig.3
inspection management and development of solution to failures. See Fig. 4.
Enterprise Risk Management ERM seeks to provide an overall risk picture for an enterprise and can increase the value of the enterprise by supporting decision-making, reducing surprises and increasing the ability to meet the enterprise objectives. ERM can be defined as a systematic approach to improve the chances of reaching enterprise goals by: understanding and ranking threats and opportunities with respect to their influence on enterprise goals controlling risks and exploiting opportunities on the basis of risk/ reward considerations considering all sources of risk (SHE, asset, project, reputation, political, organisational) a design of ERM frameworks to describe and regulate the execution of enterprise risk management an application of formal processes to implement the ERM frameworks in corporate operations and strategy considerations. See Fig. 5.
Qualification Basis
Fig.4
Technology Assessment Threat Identification Develop Qualification Plan Analysis and Testing Performance and Testing Technology Deployment
Concept Improvement
Fig.5
det norSke VerItaS aS nO-1322 Høvik, norway i Tel: +47 67 57 99 00 i Fax: +47 67 57 99 11 www.dnv.com
tHIS IS dnV DnV is a global provider of services for managing risk, helping customers to safely and responsibly improve their business performance. Our core competence is to identify. assess and advise on risk management. DnV is an independent foundation with presence in more than 100 countries.
Global services To The mariTime and enerGY indusTries Safety, health and environmental risk management Enterprise risk management
Asset risk management Technology qualification Verification
Ship classification Offshore classification
main enerGY offices aberdeen Cromarty House Regent Quay Aberdeen AB11 5AR United Kingdom Phone: +44 1224 335 000
columbus 5777 Frantz Road Dublin, OH 43017-1386 United States Phone: +1 614 761 1214
Houston 1400 Ravello Dr Katy, TX 77449 USA Phone: +1 281 396 1000
kuala lumpur 24th Floor, Menara Weld Jalan Raja Chulan 50200 Kuala Lumpur Malaysia Phone: +603 2050 2888
london Palace House 3 Cathedral Street London SE1 9DE United Kingdom Phone: +44 20 7357 6080
luanda Edificio Monumental Rua Major Kanhangulo nº 290, 2º Andar Angola Phone: +244 222 391 631
oslo Veritasveien 1 nO-1322 Høvik norway Phone: +47 67 57 99 00
paris 69 rue du Chevaleret 75013 Paris France Phone: +33 144244010
perth Level 5 216 St georges Terrace Perth, WA Australia Phone: +61 0408 006339
rio de Janeiro Rua Sete de Setembro,111/12 Floor 20050006 Rio de Janeiro Brazil Phone: +55 21 3722 7232
Shanghai House no. 9 1591 Hong Qiao Road Shanghai 200336 China Phone: +86 21 3208 4518
Singapore DnV Technology Centre 10 Science Park Drive Singapore 118224 Phone: +65 6508 3750
© Det norske Veritas AS. Design: Coor Service Management/graphic Services 1103-020. Frontcover: ©getty images