Point by point: intervention

Audrey Leon

August 1, 2014

In advance of OE’s 2014 Deepwater Intervention Forum held in Galveston, Texas, Managing Editor Audrey Leon spoke with representatives of Helix Energy Solutions, FMC Technologies, and consultant Robert Keith of R.J. Keith & Associates, to discuss topics affecting the intervention sector.

OE: I’d like to set the stage with a historical comparison.  How have you seen well intervention –both the techniques and technology involved, and the attitudes regarding it – change from when you started your career to now?

Bjarne Neumann, FMC Technologies’ Director of Well Intervention Services, Global Subsea Services:

The biggest change in well intervention during my career has been the shift from the use of riser-based intervention systems to the use of riserless intervention systems. These riserless light well intervention (RLWI) systems have had a substantial impact on the economics of performing well interventions on subsea production equipment. There have been challenges convincing operators of the feasibility of vessel–based intervention operations using RLWI, but with a nearly 20 year track record of successful RLWI operations, this technology is no longer considered unproven.

Robert Keith, R.J. Keith & Associates:

When I started, well intervention was always carried out by drilling rigs (MODUs or jackups), and depending on utilization, you had to wait and pay whatever the market rate demanded. It also meant that you paid for the rig during transit to your location, while it was being anchored up (no DP back then), the time it took to do the work, and up until it was ready to leave location. It was very expensive.

These days, there are numerous dedicated vessels, both semisubmersible and an increasing number of monohulls, that can carry out this work, almost all of them DP II or III. There are also several companies that have developed and operate intervention systems that can be deployed from an appropriate vessel of opportunity. This has certainly reduced the cost and greatly improved the scheduling of well intervention activities.

Along with this increased frequency and greater capability has come a corresponding confidence in carrying out these types of operations, augmented by developing methodologies and regulations.

Colin Johnston, Vice President, Commercial Engineering, Helix Energy Solutions:

I have seen similar developments in both the North Sea and the Gulf of Mexico, in that standard rig-based approaches with completion workover riser systems existed and were used from rigs in a consistent manner. 

In order to reduce costs, equipment was adapted and modified on a case-by-case basis, and this was supplemented by ad-hoc, “reach for the sky” projects involving various vessel and service designs and combinations which ebbed and flowed with the oil price and general activity. The more consistent underlying trend has seen dedicated vessels, refined in their design and optimized for efficiency, supplemented with intervention systems—whether riser or riserless—also optimized for their ease of application across all water depths and all tree types. This has been mirrored with the change in attitude from the “rig-does-everything” to selecting the right tool for the right job. More recently, the critical mass of subsea wells in key areas like Gulf of Mexico, North Sea, Brazil and West Africa has also seen a maturity of subsea well operations develop with long-term multi-year contracts specifically for well intervention services being applied.

OE: With large subsea compression developments underway, such as Statoil’s Asgard project and Shell’s Ormen Lange, operators Statoil and Shell have reported that they don’t believe vessels currently exist to properly service and maintain these massive subsea projects. Do you believe this to be true? If so, what solutions are available now?

Bjarne Neumann: Yes, this is true. Subsea compression systems are different from traditional subsea equipment in size and complexity. With increased complexity, and the fact that this equipment is critical for maintaining production, the operators are forced to have intervention vessels available to pull/set large modules year-round. Another key challenge associated with this type of equipment is the size of some of the components. Today’s traditional moon pool size is too small to accommodate some of the equipment and new vessel configurations may be required to handle these new systems. 

Colin Johnston: It may be the case, in the eyes of the operator, that the vessel they require does not currently exist. That does not mean that there is an impossible hurdle to get over. The capability of experienced companies to develop the solutions needed by clients has been demonstrated across the board. Helix initially developed vessels on spec. However, as client needs have matured, we have seen increasing involvement from clients to specify directly what they seek. This must be coupled with the necessary commitment to vessel contracting in order that the commercial targets of both client and contractor can be met in terms of vessel provision. Thus, similar to early well intervention needs, subsea processing and compression may remain an emerging market for specialist vessels, if the operators’ needs are different from the capabilities of the vessels currently available. I expect it is only a matter of time before those needs are raised by clients, and the contracting community will respond if the commercial rewards are there. I am of the opinion that existing vessel capability and design is fundamentally what is needed, but I believe the subsea interface and intervention capability is where the development should be focused.

Charting Intervention. Illustration from FTO Services.

OE: Other than vessel availability, what other limitations have you encountered (regulatory or otherwise), if any?

Bjarne Neumann: One of the greatest limitations to the expansion of intervention services is the lack of the appropriate infrastructure needed to support the demand. That, and the need to train the personnel necessary to deliver the services, is going to be a greater challenge than vessel availability.

Robert Keith: A big limitation on carrying out work is the operators and what their various corporate policies are on interventions. They are particularly concerned about contingencies and processes in the event of a DP failure, and ensuring the security of the well and its contents, which is certainly justified, but a common guideline would be advantageous.

Colin Johnston: One area of improvement is for clients and service providers to work together to improve how vessel mobilization and sharing is administered, along with operational planning, across all aspects of field development, maintenance and decommissioning. This would realize overall cost savings through efficient application and, ideally, a certain amount of autonomy applied, or made available within asset groups, to best use the available vessels, systems and services. Viewing overall costs on a production equity basis would see the vessel and services being applied across the board to the betterment of the field development and maintenance requirements.

OE: One topic I have been hearing a lot about at conferences is standardization, in regards to equipment, as one way to bring down high industry costs. Do you believe interface standardization, especially on subsea processing systems, could be helpful for intervention purposes? How would the industry best handle something like this?

Robert Keith: While standardizing interfaces should be an obvious solution for reducing costs, it is apparent that the drive for innovation and development combined with the egoist need to re-invent or just be different, has resulted in several variations, much to the chagrin of the contractors and their ever-expanding tool kit to carry out a single task. 

The API standards are excellent guides for designing interfaces and tools, however, they have to be adopted and then followed by the operators and equipment manufacturers. This is further exacerbated by having multiple standards around the world, which, with true international trade, especially amongst the installation contractors and vessel operators, meaning that they must carry a suite of tooling to meet all of the various interfaces. 

I believe that a global standard should be agreed upon and adopted so that the correct tooling is always available. This would simplify design, and thereby reduce complexity, reduce cost, and improve efficiency, thereby further reducing cost.Colin Johnston: Standardization is the outcome of the focus on regulatory oversight since it is easier to monitor and regulate something that is standard in terms of its application. Consequently, the emphasis within the subsea well operations community is on subsea pressure control equipment standardization with the emphasis on well control and re-entry capability in the event of a major incident. The subsea well operations community has effectively rallied around this cause with significant voluntary support to ensure we have an across-the-board agreement on what subsea pressure control equipment should look like now, and in the near future. The industry is currently handling this very well through the ISO and API process involving, I am pleased to say, both operators and service companies.

Overall interface standardization is helpful for the industry but will be only marginally beneficial in terms of the barriers to entry to the business. The ability to design, build, procure and maintain the necessary systems will rely more on those companies fully committed, experienced and immersed in the subsea well operations business environment to deliver what operators require. Additionally, the operators’ level of comfort can only be optimized when those supplying companies can back up the physical equipment offered with the expertise and in-depth knowledge of how best to apply and operate the equipment, whether vessel or subsea, in the most safe and efficient manner.

OE: Last October, OE ran an article from Welltec and Anadarko about Anadarko’s “warming up” to riserless light well intervention (RLWI). Do you feel that there are misperceptions about RLWI in the industry? Are you seeing a shift toward its use for maintenance operations, or will heavy intervention vessels still be favored as the most preferred option?

Bjarne Neumann: There is a lack of appreciation for what RLWI systems are capable of these days and a lack of understanding of what can be achieved using these systems. We have seen a tremendous increase in the variety of downhole tools which has, in turn, enabled RLWI to take on more tasks normally associated with riser-based intervention. Typical tasks being undertaken today using RLWI include well logging, re-perforating, side pocket mandrel replacement and scale/hydrate milling.

While Anadarko’s venture into RLWI was not entirely successful, there was some benefit gained in the form of “well knowledge.” This enabled a better understanding of the task that would need to be performed if it proved financially viable to recover the well. The information gained can be used as a basis of planning appropriate operations and the mobilization of a rig with the correct equipment, rather than an excessive inventory of inappropriate tooling. 

Robert Keith: It really depends on what you are trying to do. RLWI is ideal for many “simple” intervention operations like pumping or changing out valves, and does not require the larger, more expensive dedicated intervention vessels that are now available.

Conversely, more intricate operations, further downhole and in more complex wellbores, require a suite of tools and more advanced well control capabilities that are part of dedicated well intervention vessels.

Ultimately, the decision of what methodology to use rests with the relevant regulatory body (BSEE, DOE, et. al.) and the operator, and what their policy is and the level of confidence they have in a contractor and their capabilities.

Colin Johnston: This aspect of either/or with regards to RLWI and riser-based (heavy intervention) continues to crop up. In my opinion, it is about operational risk assessment and applying the right tool for the job. In the key deepwater basins there is optimum opportunity to apply what is needed that enables all relevant players to utilize their assets to the benefit of operators. I believe that within subsea well operations, specific niches will be supplied by those vessels and systems that are perfectly tailored for what they do, whether that is simply data gathering or full through tubing intervention involving stimulation, scale milling, fishing or other production enhancement. 

I do not believe there are fundamental misperceptions regarding RLWI, Helix has been conducting such operations since 1990, but I do believe there are conflicting reports regarding method of application and efficiency gains. Both riser-based and riserless are sufficiently mature now that one is not a safeguard for the other, that is to say they are both key services in their own right. Preferred is not the issue – it is being able to apply the right service at the right time and at the right price. I believe only those companies with the full breadth of knowledge of what it takes to provide an integrated service for clients will truly leverage the opportunities offered by both RLWI and riser-based intervention. 

OE’s Deepwater Intervention Forum will be held this August 12-14, 2014, at the Galveston Island Convention Center. For more information, please visit: www.deepwaterintervention.com.