The offshore market recognises that hydraulic pumping light well intervention (LWI) has the potential to significantly increase the productivity of many subsea wells, from high pressure injection of chemicals through to scale squeeze and formation fracking, designed to stimulate higher rates of productivity from reservoir formations.
70% of all operational subsea wells are now in excess of 5 years old and productivity is decreasing. With global demand for oil and gas still increasing, production costs rising and oil prices still depressed, light well intervention activities are naturally growing, as they allow higher oil production with minimised CAPEX. Light well intervention costs are also significantly less than new field costs, with the cost per barrel from intervention around one tenth the production cost from new fields, hence the steady recent growth of light well intervention. Average recovery without regular intervention is only 22% of available oil (Offshore Network report 2015). Based on the remaining 78% of global hydrocarbon reserves in subsea assets that could be recovered through intervention, just a 1% increase in recovery would be equal to 90 Billion BPD or the equivalent of 3 years of full global production at current levels.
Within the light well intervention market, hydraulic LWI market is still currently small and developing, but with significant potential. Whilst there is evidence that light well hydraulic pumping activities are already being contracted by some operators, the intensity of such activities is significantly lower than the industry might expect. The fact is that many people are talking about it, but few are doing it, for a whole range of different reasons, and many of which are also related to the limitations and risks of existing pipe technology. One of the biggest challenges is the number of subsea wells now operating in deeper water, where rig availability is more limited and their rates are higher than vessel costs for intervention work. This is another key reasons that the offshore industry does not already have a larger and more active sector focused on delivering efficient hydraulic light well intervention, as it has traditionally had reservations about the capabilities and risks of using smaller but cheaper and more readily available vessels for well intervention work.
For intervention the industry has successfully employed coiled tube and, to a lesser extent, non bonded flexible and jointed steel pipe for chemical injection operations. When such operations have been undertaken in shallower water under 300m (1,000ft), this has been relatively successful, as the pipe products are relatively cheap and intervention operations only require low intervention fluid pressures and medium-level flow rates. However, as depths, pressures, flow rates and the nature of the intervention fluids becomes increasingly challenging, existing coiled tube, steel and non bonded pipes reach the very limits of their design capabilities and other challenges that come from their relatively short life span. From conversations with large intervention contractors, Magma understands that the pipe factor is the key reason that they have been reticent to offer deep water fluid pumping services. This means that valuable intervention work is either avoided, missing potential production upsides, or conducted using a more expensive and complex MODU and full workover package. Coiled tube, drill pipe and non bonded flexible pipe have well-known issues that impact intervention service efficiency, pipe life and that limit their scope of application and the future successful expansion of the hydraulic stimulation market. There are many common challenges with existing pipe that include fatigue sensitivity, complexity of pipe management for vessel deployment, limited corrosion resistance, high relative deployment weight, limited diameter and pressure capability, limited intervention fluid flow rates and pipe longevity, longevity and associated replacement cost and the need for regular operational re-spooling.
The Magma intervention strategy has been to focus on the two key elements – a downline pipe specifically designed for deep water intervention, and an integrated compact back-deck vessel deployment system. This combination is developed with the objective of maximising the technical feasibility of hydraulic LWI operations, to accelerate the growth of this important market and to deliver against the immediate potential of maximising production and minimising cost and risk. Magma m-pipe® is a light, strong and flexible carbon fibre fluid delivery pipe, and the key component that delivers the high pressure intervention chemicals to the wellhead. In reality m-pipe® is a dynamic deep water riser system that delivers against all of the design and operational complexities that deep water, high pressure and high flow rate hydraulic intervention systems require. m-pipe® addresses the limitations of existing LWI pipe and is a high performance subsea riser pipe:
The fatigue resistance of m-pipe® is a key aspect of the system’s reliable intervention performance, as the pipe can be reeled thousands of times without significant degradation. Such resistance also means that the system can accommodate larger vessel motions during deployment, maximising operational windows and intervention campaign up time.
The Magma IDP is a single vessel back-deck package that manages all aspects of the m-pipe® riser including transportation, deployment and retrieval. It is compact and relatively lightweight and is specifically designed to fit on the back deck of small light well intervention vessels, construction vessels or even directly onto a stimulation vessel.
The IDP shown is designed for 3,000m (10,000ft) of 3in 15ksi pipe but the same unit can also be used for 3in 5ksi or 10ksi pipe. The pipe is loaded into the reel in three sections and stored in separate partitions, allowing a single, double or triple length to be deployed depending on application depth. The key benefit of this approach is that it provides operational flexibility and hydraulic efficiency. The latter is important as it avoids the need to pump through the whole pipe length on the reel when deployed in shallow or intermediate well depths. The IDP also includes all aspects of pipe handling and other equipment such as LRP, EDP, buoyancy and ballast weights, all optimised for safe, efficient and reliable operations, through a moonpool or over the vessel side. The integrated m-pipe® and IDP system can also be combined with other packages and services from operators to provide a complete, cost effective and reliable service for deep water hydraulic pumping operations, including emergency disconnect packages, subsea tree and manifold connections, Intervention chemical storage and pumping and an ROV spread.
By providing an effective packaged solution to all of the critical technical and commercial components in a hydraulic well stimulation system, including the riser and its delivery system, Magma’s m-pipe® and IPD system facilitates the entire well pumping process, allowing easier access by operators through a day-rate rental system, and increased confidence for contractors to deliver effective hydraulic LWI pumping operations. The combination of the Magma IDP system and high performance m-pipe® downline ensures ease of operation and allows multiple hydraulic light well intervention operations over a period of many years, taking advantage of the longevity and fatigue resistance of m-pipe® and offering a complete and commercially attractive packaged rental solution. The Magma IDP system and m-pipe® is set to help to rapidly build a nascent LWI market, allowing operators to more easily take advantage of hydraulic stimulation methods and deliver the additional production at the lower cost per barrel that the oil industry urgently requires.