OTC 17060

Remote Subsea Intervention - An Enabling Technology or Not? An Installation Contractor's Perspective S. Macknocher, Stolt Offshore M.S. Ltd

Copyright 2005, Offshore Technology Conference This paper was prepared for presentation at the 2005 Offshore Technology Conference held in Houston, TX, U.S.A., 25 May 2005. This paper was selected for presentation by an OTC Program Committee following review of information contained in a proposal submitted by the author(s). Contents of the paper, as presented, have not been reviewed by the Offshore Technology Conference and are subject to correction by the author(s). The material, as presented, does not necessarily reflect any position of the Offshore Technology Conference, its officers, or members. Papers presented at OTC are subject to publication review by Sponsor Society Committees of the Offshore Technology Conference. Electronic reproduction, distribution, or storage of any part of this paper for commercial purposes without the written consent of the Offshore Technology Conference is prohibited. Permission to reproduce in print is restricted to a proposal of not more than 300 words; illustrations may not be copied. The proposal must contain conspicuous acknowledgment of where and by whom the paper was presented. Write Librarian, OTC, P.O. Box 833836, Richardson, TX 75083-3836, U.S.A., fax 01-972-952-9435. Abstract As Installation Contractors fight to survive in the risk loaded world of EPCI/EPIC Contracting, many are starting to question which technologies they need to retain in order to successfully support their core business of Installation and Subsea Construction. These technologies are sometimes referred to as 'enabling technologies' and are defined as those required to execute the Contractors core business, i.e. they cannot, or should not be out-sourced. To date, most Installation Contractors who are active in deepwater locations Worldwide have treated Remote Subsea Intervention as an enabling technology. However as Remote Intervention in deepwater becomes an established and accepted technology, should it continue to occupy such status within a Contractor's organization?

This paper aims to review the development of Remote Subsea Intervention within Contracting Companies and to examine the criticality of this technology to such Organisations ongoing business. Furthermore, current Remote Subsea Intervention technology appears to have reached a position within the industry where it is considered to be mature and indeed sufficient for todays needs. Whilst this perception may be correct, there is surely a danger in assuming that what we have is good enough and will continue to fulfil the future needs of the industry.

Finally, against a background of the industries need and desire to advance into frontier areas (i.e. ultra deepwater), the paper aims to examine alternative approaches to achieving cost effective, yet reliable and efficient Remote Subsea Intervention in the future.

Introduction Recent years have seen many established Subsea Installation Contractors suffer poor financial health resulting from losses incurred during precedent setting, yet low margin deepwater developments executed under demanding contracting terms. The advent of these EPIC type contracts led to increased scopes of work which led many contractors to expand their portfolio of in-house capabilities. In otherwords, previously out-sourced technologies were either developed internally or obtained through acquisition as Contractors tried to mitigate risk by taking control of key equipment and services. Furthermore, significant consolidation took place as the sector tried to address the oversupply, which existed during the 1990s, examples of which are Stolt Offshore/ETPM, Saipem/Saibos and Technip/CSO. However, as the number of deep and ultra-deepwater field developments increase, the supply and demand equation appears to be levelling out, with the availability of key marine assets and engineering resources becoming tight. Yet even within this improving environment, Contractors appear to be re-focussing on their true core business of Subsea Installation and Construction as a way of returning to profitability and managing their risk profile going forward. Part of this re-focussing involves achieving the correct internal/external capability balance through initiatives such as asset reduction, divestment of non-core activities and joint venturing.

But how does an organisation decide which capabilities or

technologies are retained and which can be out-sourced?

Control Required over Product or Service

Figure 1 : Technology Ownership

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Usually, it is those technologies, capabilities and assets that enable an organisations core business that are considered essential and therefore retained in-house. Figure 1 depicts this decision making process in simplistic form. Indeed, over the past year or so, the term Enabling Technology appears to have been adopted to describe such capabilities that are considered to be of such importance that they must be controlled and cannot therefore be out-sourced. But what is an Enabling Technology?

In simple terms, these are fundamental technologies or capabilities that enable core applications or activities to work. Therefore, in the case of Subsea Installation and Construction, we mean those technologies or capabilities that make the installation of subsea infrastructure feasible or possible, including:

- Engineering and Project Management - Deepwater Pipelay - Riser Technology - Remote Subsea Intervention

And associated with these Enabling Technologies are

Enabling Assets such as:

- Installation Ships or Barges - Pipelay Equipment and Spoolbases - Remotely Operated Vehicles (ROVs) - Specialised Deployment Equipment

For the purpose of this discussion, it could be argued that

the opposite of an Enabling Technology is a Commodity which can be defined as a technology or service that is interchangeable with another product of the same type, the price of which is subject to supply and demand. Making this distinction between Enabling Technology and Commodity helps us to understand the technology landscape with respect to Subsea Installation and Construction and to make decisions as to those activities which must be closely controlled, nurtured and developed, and those which can be bought as required.

But where, in this examination of Enabling Technology does Remote Subsea Intervention fit?

Without doubt, this is a technology that has, since the advent of deepwater development, become critical to the success of Installation Contractors. Without successful Remote Intervention capabilities, Contractors would have been unable to execute complex, deepwater development projects. Whilst there have been problems along the way, here is a technology that has evolved to a point where it appears to meet the needs of the industry with regular operations being reliably performed in water depths of 1,500m and beyond. Therefore, could it be that Remote Subsea Intervention has evolved from being an enabling technology to that of a commodity? Furthermore, if this is the case, can we assume that Remote Intervention will continue to meet the complex challenges of ultra-deepwater without further development? And do Contractors, who rely on this technology on a day-to-day basis, need to maintain the direct involvement that we see

today? To answer this question, it is important to firstly consider the history of Remote Intervention within the Installation Contractor community. History and Experience to Date The majority of todays main Installation Contractors have evolved from Companies with a diving, or pipelay heritage, and in many cases, this has led to Remote Subsea Intervention being developed or acquired on an as required basis. As long as diving was available, this was justifiably the preferred option given that remote technology was relatively undeveloped, and could not match the efficiency or reliability of diving as a means to intervene in the subsea environment. However the advent of deepwater exploration and subsequent development, particularly in frontier areas such as Brazil, forced the hand of Contractors and Remote Intervention subsequently became part of their daily toolkit. However, the methods by which Contractors have accessed this capability have varied considerably. In terms of the enabling equipment, namely ROVs, each company has taken a different route, but has ultimately ended up with the same result.

Technip, formerly Coflexip Stena Offshore, acquired US based ROV manufacturer Perry Tritech and subsequently expanded this operation with the capture of Slingsby Engineering, thereby gaining control of one of the largest manufacturers of Subsea Intervention systems world-wide.

Figure 2 : Stolt Offshores SCV3000-1A

Stolt Nielsen Seaway became the first main diving

contractor to operate Workclass ROVs in the North Sea when they introduced the Scorpio#02 in 1978. But as the importance of Remote Intervention increased, particularly in Norway as the drive to introduce, and indeed eliminate diving gathered pace during the early-to-mid 1990s, the company (then Stolt Comex Seaway) developed an in-house design capability which culminated in the first large scale build of ultra-deepwater ROVs. The SCV3000 (Figure 2) was first introduced in 1997 and continues to be built by Stolt Offshore today with over 25 of these units having been produced to date (Figure 3).

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Like Technip, Saipem achieved control over Intervention equipment design and manufacture through acquisition, but took this one step further by purchasing an active ROV operator. In Sonsub, Saipem attained in-house designed and built ultra-deepwater Innovator ROVs, that have operated in almost 4,000msw during the Prestige oil recovery operation.

Finally, Siem Offshore (previously Subsea 7) built its capability on a long-term, in-house development effort, which took it to the forefront of subsea intervention expertise, particularly in the North Sea, and the then frontier area of West Shetland and its pioneering deepwater tooling systems. Today, Siem Offshore maintain this in-house capability, although on a scale somewhat reduced from its heyday of the late 1980s and early 1990s.

The foregoing potted history of intervention equipment and in particular, ROVs shows us that Contractors recognised the importance of Remote Subsea Intervention to their evolving businesses and reacted by not only attaining this new technology, but by gaining full control over it, albeit through very different means. But how successful have these initiatives been?

Over the past three to four years, the subsea contracting industry has moved from a position where deepwater operations were sporadic in nature, to a position today where the majority of day-to-day challenges lie in water depths beyond 1,000m and regularly in depths over 2,000m. The scale of subsea developments in ultra-deepwater such as Girassol in West Africa and Na Kika in the Gulf of Mexico has meant that without reliable and efficient Remote Intervention capabilities, Contractors would have been unable to successfully execute such projects. This simple fact has driven Remote Subsea Intervention to a level of reliability where this capability is today considered to be a key, yet mature part of the Contractors portfolio of enabling technologies. As such, we can conclude that this philosophy of treating Remote Intervention as a key technology, requiring full ownership or control has been successful. But this has not always been the case.

Figure 3 : Pile Installation from Seaway Polaris

Initial efforts to move into deepwater frontier areas proved problematic at best. With hindsight, the move from relatively shallow water operation (500m) and beyond required a step change in Remote Subsea Intervention which was not necessarily appreciated by Contractors prior to the need becoming reality. The complexity of operations increased dramatically, with equipment and personnel being expected to expedite a high level of difficult critical path parallel activities, often without the necessary preparation or training. Furthermore, the increased depth requirements brought obvious challenges in terms of greatly increased ambient pressures and higher top (surface) tensions, however initially at least, it was the less obvious areas of the equipment spread that gave the majority of problems. In fact, the main faults encountered related not to the ROV itself, but to the array of ancillary equipment required to deploy and support operations at such depths, examples of which are as follows: - Deployment umbilical failure (specifically the internal

optical elements used for communication) - Deployment winch failure - Buoyancy degradation and collapse - Surface launch and recovery systems - Interconnecting cables and connectors - Tether and Tether Management System (TMS)

In fact, general ROV unreliability accounted for a minority of breakdown, and once equipment became acclimatised to working depths, it tended to perform well. However, there was a far greater issue, which although seemingly obvious, compounded every problem encountered and made the consequence of each failure, be it equipment or process related, far greater than anything experienced previously. This was the time to deploy and recover equipment and subsea infrastructure to and from the required depth.

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Figure 4 above shows in basic form, the impact of operating in deep and ultra-deepwater compared to the conventional shallow depths that the industry was used to prior to commencing regular deepwater operations. In simple terms, the time taken to deploy equipment from surface to working depth and back to surface increased from minutes to hours, and for Installation Contractors, this change in their operating model was significant.

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Equipment failure or in many cases simple operational inefficiency such as the need to continually return to surface became significant because of the consequential non-productive vessel time experienced. In otherwords, if the ROV or associated Intervention tooling was unavailable, the entire construction vessel or barge was unable to work. Given that the [selling] cost of premier, deepwater construction vessels can exceed $150,000 per day, the impact becomes apparent. Examples of such operational inefficiency are listed below: - Equipment breakdown - The inability to plan several tasks sequentially without the

need to return to surface - Interface between intervention systems and subsea

infrastructure - The historical factor whereby the time to depth was not

considered in shallower depths - Suitability of Client provided items for Subsea

Intervention

However, these factors were only really discovered once regular and large-scale deepwater operations commenced, and as such, improvement took place through incremental means rather than the step-change that was actually necessary. That said, the industry has made progress towards improving overall capability and efficiency, some general examples of which are: - Improved flexibility at depth (e.g. subsea tool changeout

and increased ROV payload) - Overall system reliability improvement through:

- Qualification testing of components - Greater integration testing (SIT, etc) - Training

- Faster launch and recovery systems - Parallel ROV operations - Advanced Project task planning

However whilst steps to improve have undoubtedly been made, it is almost certain that the current status quo cannot be sustained as the industry moves towards regular ultra-deepwater operations. Ever increasing depths will simply exacerbate existing problems, and the step change that has already been identified, still requires to be taken.

Therefore to conclude on experience to date, Installation Contractors have attained deepwater Intervention expertise through in-house development or acquisition, and the approach has been such that this capability now occupies an important position within a Contractors portfolio of enabling technologies. Remote Subsea Intervention has evolved to a position whereby it appears to meet the general needs of deepwater Installation Contractors, however further progress is certainly required before regular and efficient intervention is performed in ultra-deepwater in support of installation, construction and field development activities. Therefore as Installation Contractors emerge from a difficult period with renewed optimism, a growing market, and the challenge of regular ultra-deepwater operations, will Remote Subsea Intervention continue to occupy its status as an Enabling Technology within Contracting organisations?

Remote Subsea Intervention: The Future Recent examples of pioneering Remote Intervention (e.g. Prestige1 oil extraction) suggest that this technology is not the Industrys biggest challenge if the goal of production in water depths of 3,000m and beyond is to be achieved in the near future. Bigger challenges loom, particularly in areas such as riser systems, flow assurance and deepwater deployment, therefore we can assume that the subsea industry as a whole will [rightly] concentrate development effort on such issues.

Through our overview of the history to date, we have recognised that further development of Remote Intervention is however required, both in terms of equipment and process. But will this happen if Remote Intervention is considered to be reasonably mature and not necessarily a top priority for Contractors. The obvious alternative is to rely on external parties to undertake the development required. But without firm commitment from Contractors, this may be asking too much for independent suppliers to fund developments aimed at complex, harsh environment applications based on no guarantee of recovering their investment. Furthermore, experience has shown that when such developments have taken place, innovative design is often spoilt by a lack of understanding of the operational environment and the true needs of the Contractors. Even when successful independent development takes place, our industry is notoriously conservative when it comes to acceptance and commitment to new products, even when benefits are likely. More importantly, by reversing the trend of in-house development of Remote Intervention Technology, Contractors are, by default, beginning to consider this technology to be less important than previously was the case. In terms of the technology ownership graph depicted previously, any effort to externalise this capability represents a move towards partial ownership and a perception that Remote Intervention is not highly critical to the business of Subsea installation and Contracting. In fact, this is a dangerous scenario, which in theory at least, portrays Remote Subsea Intervention as little more than a commodity that can be sourced, from different suppliers on an as-and-when-required basis. But is this over dramatising what is potentially nothing more than another outsourcing exercise.

Here, I believe, is the pivotal issue in this discussion. Remote Subsea Intervention has now become more than just a service that can be called upon when required. It is certainly more than just something that happens as part of the execution phase of a Project. When considering large, complex, deepwater developments, Remote Intervention is evolving towards a position where it must become part of the internal structure of any such Installation Project. This applies not only to the execution phase, but throughout the life of the Project, from tendering through to hand-over to client. Indeed, Remote Intervention is now a life-of-field activity, and long after the construction phase is finished, maintenance, repair and eventually decommissioning will require some form of successful Subsea Intervention. 1 Saipem/Sonsub have recently completed operations to remove stored oil from the sunken tanker Prestige in water depths exceeding 3,800m (>12,000ft)

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In the world of complex deepwater developments, the improvement opportunity curve as shown below in Figure 5 is as applicable to Remote Intervention Technology as it is to higher profile issues such as subsea production systems or riser design and installation.

Figure 5 : Development Impact

But this evolution is, as yet, not fully complete. Too often, problems associated with the installation of subsea infrastructure are solved during the execution phase, where the opportunity to reduce cost is at its lowest. In reality, by the time offshore operations are commenced, the best we can hope for is to minimise the losses, because problems encountered during operations will usually take longer to resolve and cost more than planned. So what is required to complete this evolution whereby Remote Subsea Intervention becomes integral to the entire, ultra-deepwater field development process?

Firstly, ROV systems and intervention tooling is already rated for these depths as are subsea hardware components, therefore future initiatives for improvement must target the pre-operation phase. In general, advances must be made which improve overall operational efficiency throughout the field development process and in particular, in the following areas: - Full integration of Remote Intervention Technology into

the design process - Identification and adoption of operational best practice - Standardisation of interfaces, intervention tooling and

procedures - Improved interface between Installation Contractor and

Subsea Production System (SPS) supplier - Experience feedback and adoption of lessons learned

By adopting a consolidated approach to Remote Subsea Intervention, we can develop standard methodologies to all operations in ultra-deepwater which are; 1. Repeatable: - based on best practice 2. Reliable: - we know it will work 3. Efficient - when we adopt best practice and it

works then we are efficient

Repeatability + Reliability = Operational Efficiency

In reality, many factors go towards achieving the above equation for success, but as the complexity of subsea operation continues to increase, personnel are expected to undertake a high level of difficult, critical path activities on a daily basis. If acceptable levels of operational efficiency are to be achieved, personnel must be provided with new technology which complements current levels of expertise thereby ensuring improvement, particularly with respect to critical activities. An example of such new technology is visualisation.

In recent years the software and hardware technology to enable visualisation to be used in the subsea sector of the industry has come of age (Figure 6). Visualisation can be used across the spectrum of our activities from the FEED stage through to live operations offshore. Three-dimensional drawing packages have been used for a number of years for draughting and for producing marketing animations and these are now being used to produce offshore procedures. This medium is ideal for developing installation procedures, particularly for complex riser installation work or for accessibility checks. Visualisation is ideal for familiarisation and training of Project personnel during operational reviews, risk identification and during offshore briefings prior to actual operations.

Figure 6 : Visualisation offers a step-change in subsea operations

(Image courtesy of Century Subsea)

Furthermore, this technology can also be used to provide a live visual presentation of the subsea worksite during operations (Figure 7). The positions of vessels, ROV systems, deployment lines and subsea components such as manifolds or suction anchors can be presented in real time during installation. This real-time animation which, can be viewed onboard the construction vessel(s) offers a genuine step change in how operations are performed. The use of such live visualisation will certainly improve the efficiency of intervention operations by providing an enhanced navigation display for the operators. This would be particularly useful in low visibility conditions or for operations being performed amongst complex subsea structures and risers. Technology already exists to enable the video and visualisation displays to

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be transmitted onshore so that offshore operations can be monitored by the Contractors Project office and by the end Client. Further development could lead to a Dynamic Positioning capability for ROVs, whereby a vehicle could be automatically directed to move to specific locations, whilst avoiding existing infrastructure. This capability could be used for large-scale survey tracking operations, or for automatic positioning during touchdown monitoring of pipelines during installation.

Figure 7 : Typical Visualised Field Infrastructure

Full implementation of this technology will require commitment from all parties, however assuming its use becomes widespread, it will offer significant benefits and go a long way towards achieving the step-change required to enable regular, ultra-deepwater subsea intervention.

Another technology, which is likely to become influential in terms of Remote Subsea Intervention, is that of Autonomous Underwater Vehicles, or AUVs. In recent years, AUV technology has evolved from its academic and oceanographic roots and is now playing an active role in geophysical data acquisition within the survey sector of the oil industry. These untethered vehicles are capable of travelling a pre-defined route gathering detailed seafloor and shallow sub-bottom profile information, before returning to pre-defined locations where they are recovered and their data retrieved. Without doubt, progress to date has been impressive, although today, AUV technology is not capable of direct participation in subsea installation or construction operations, due mainly to the dynamic nature of such activities. However, further development is underway which aims to apply this technology to pipeline survey and inspection operations using the concept of a hovering AUV. If fully industrialised, the use of AUV technology in such a way will undoubtedly interest Installation Contractors, particularly if activities such as real-time touchdown monitoring of pipelines can be achieved.

If AUV technology can ultimately produce a true autonomous work vehicle for field intervention, this will have a significant impact on ultra-deepwater field development, although this is likely to be in the area of life-of-field

inspection and routine maintenance rather than initial installation and construction.

Whilst the design for such a vehicle is slowly being

progressed, it is almost certain to be at least five years before such systems are available for regular use. Unfortunately, the message from many parts of the industry appears to be that AUVs are the future. The reality is that AUVs are part of the future, and just how big a part remains to be seen.

In summary, Remote Subsea Intervention has been performed successfully to depths approaching 4,000msw, however such instances tend to have been isolated thus far. In truth, the efficiency achieved during ultra-deepwater operations to date is unlikely to be sustainable once regular, large-scale developments become commonplace for Installation Contractors. Therefore, a true step-change is required, whereby Remote Subsea Intervention becomes fully integrated into field development Projects. Additionally, there must be significant improvement in the interface between Installation Contractors and subsea infrastructure vendors such as SPS suppliers. Too often, equipment is designed with little of no thought to the installation case & the subsequent issue of remote intervention, not only during the installation phase, but during life-of-field maintenance and repair.

This step-change will require a combination of: 1. Incremental improvement to existing equipment and

hardware. 2. Integration of Remote Intervention Technology expertise

and thinking throughout each phase of Project development.

3. Introduction of new technologies such as visualisation, not only to the operational phase, but throughout the entire Project life.

Conclusion The development of Remote Intervention Technology has occurred, to some degree, by default. Increased operating depths have forced subsea operations outwith the reach of traditional saturation diving, and as water depths have increased, so too have the complexity of installation equipment and subsea hardware.

For Installation Contractors, Remote Intervention is a key enabler in terms of assets and operational personnel involved, in addition it should be recognised that intervention engineering is also a key enabler, providing it is introduced early enough as it has a huge impact on the end result.

Therefore to conclude, Remote Subsea Intervention is undoubtedly an enabling technology for Installation Contractors operating in deepwater provinces around the world. However, as operating depths continue to increase, the importance of this technology will grow, especially for those Contractors involved in Umbilical, Riser & Flowline (URF) Installation. As such, this technology must be treated accordingly, and afforded a high priority in terms of

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development effort, and control. The benefit to Installation Contractors of initiatives such as the internal design and build of intervention equipment cannot be underestimated as the entire sequence of equipment development, design, and most importantly operation, generates an internal capability that cannot necessarily be maintained if it is outsourced.

Remote Subsea Intervention may have become an established and accepted technology over recent years, but there is no room for complacency. Its importance to the Subsea Installation Contractor has never been higher and accordingly, must retain its status as an Enabling Technology without which, regular and efficient deepwater installation and construction operations may not be achieved. Nomenclature AUV = Autonomous Underwater Vehicle EPCI = Engineer, Procure, Construct and Install EPIC = Engineer, Procure, Install and Commission FEED = Front-End Engineering and Design Msw = Metres of Sea Water ROV = Remotely Operated Vehicle SCV = Stolt Core Vehicle SIT = Site Integration Testing SPS = Subsea Production System TMS = Tether Management System URF = Umbilicals, Risers and Flowlines

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