Consistently underpinning technology advances in the upstream oil and gas industry is an emphasis on maximizing efficiencies and reducing costs. Innovative technology provides the industry with new opportunities, helping to unlock reserves and achieve greater efficiencies.
While it appears that the worst is over, the three-year oil price recession presented unprecedented challenges for the industry and created a seriously challenging environment. Cost-cutting was the norm, as companies addressed the new reality, in order to survive and sustain operations.
The key to establishing a more sustainable future has been the investment in new technology. Technology, people and collaboration are, and will remain, a firm focus for the industry, with the three factors intertwined and helping companies to advance and survive. Technological advances have played a significant role in transforming the sector; even more so in recent years, as they help identify and develop resources, achieve objectives faster and more efficiently, and have optimized production and operations.
Advances in drilling already have helped reduce the surface impact of operations. Yet, with drilling and well construction accounting for the majority of cost and risk in upstream operations, operators are looking for innovative technologies that can reduce costs and add value to operations without compromising safety. This has become a greater priority recently, as the industry looks to maximize recovery, and as work occurs in ever-more challenging environments and locations on more complex wells. According to OPEC, recoverable resources have more than doubled since the 1980s, due to advances in technology. For example, where we used to be able to drill only meters below the surface, new technologies are now enabling us to drill kilometres below the surface.
Innovation and collaboration are required to address the challenges facing the drilling sector, with collaboration becoming almost as important as the new technology. Both are a key focus for the industry, and the establishment of innovation centers, such as The Oil and Gas Technology Centre (OGTC), demonstrates the investment and commitment in this area. The OGTC promotes a collaborative approach and assists with the development, trial and commercialization of innovative technologies.
The OGTC received ￡180 million in funding, to be invested in the North Sea with the aim of maximizing economic recovery on the UK Continental Shelf (UKCS). This bolsters the supply chain and ultimately promotes and encourages an innovative mind-set in the region. There are five key areas that have been identified as significant by the OGTC—asset integrity, marginal developments, decommissioning, digital transformation and, of course, wells.
Referring to the UK drilling market, the OGTC claims that by reducing well delivery costs as much as 50%, up to 5 Bboe could potentially be unlocked. Additionally, with 30% to 50% of the UKCS’s capital expenditure allocated to well construction and management, new and innovative technologies are needed to sustain reduced costs and maximize economic recovery. The OGTC has been supporting the development of well technology, particularly for small, innovative companies that are set to have a huge impact on a traditionally conservative industry.
RECOGNIZING THE NEED FOR CHANGE
With purse strings being tightened but the need to operate safely and efficiently a non-negotiable priority, solutions that can assist in optimizing drilling operations by simultaneously increasing productive time and reducing costs are being sought. Recognizing the growing need for reductions in cost and risk, DeltaTek Global was launched in 2015, in response to the growing requirement for efficiently implemented, intelligent, cost-saving and risk-reducing products.
Our mission is to save rig time, using cleverly-engineered technology. The company specializes in well construction and has developed innovative technologies that are applicable to all subsea well projects, regardless of depth. The two primary technologies, ArticuLock and SeaCure (Fig. 1), have been designed to save rig time by either extending the weather window for any subsea deployment or optimizing cement jobs.
The company, which has received funding from OGTC and Scottish Enterprise, has been working closely with OGTC. The center has supported DeltaTek’s entrance into the drilling market by connecting the company with key industry contacts and facilitating a number of field trials in the North Sea with major players.
How events have unfolded for our company is a perfect example of collaboration in practice, and the benefits that it can bring to all stakeholders. It has been a genuinely collaborative process between our team, our investors and operators. Innovative technologies are key to reducing cost and risk, particularly as we start to work in more challenging locations. The biggest hurdle initially is being able to demonstrate results to prospective clients. Quantitative results are crucial, and if you are unable to show significant cost-savings and benefits over current methods, the willingness to even consider a new technology can be limited.
This is why collaboration is so important across the industry, as it encourages companies to think outside the box and find new ways to address industry challenges.
ARTICULOCK–CONTENDING WITH THE ELEMENTS
The remote and harsh environmental conditions offshore present significant challenges, and they contribute to increases in non-productive time and cost. At the mercy of the elements, offshore drilling operations can be prolonged by high winds and increased wave movement that intensify rig movement, which can destabilize equipment. This is an age-old problem for the industry, and it has meant having to down tools and wait for calmer weather. This creates a short window in which work can be completed in the North Sea, and it leads to high levels of unproductive time and rising costs.
DeltaTek’s ArticuLock system addresses this issue by extending the window for deploying subsea equipment by countering increases in rig movement. Behaving much like a camera gimbal, the proprietary system is essentially a ball-and-socket joint that removes bending stress from the subsea equipment. By removing the bending stresses caused by increases in rig movement, it stabilizes equipment and enables work to continue in weather conditions that would have previously suspended operations.
Earlier this year, ArticuLock underwent rigorous field trials on the Stena IceMAX drillship (Fig. 2), offshore Las Palmas, which were supported by the OGTC and a result of the collaborative working group between DeltaTek, OGTC and Stena Drilling.
ArticuLock is fitted to the drill pipe landing string, and it can be locked and unlocked manually or by an ROV, as, and when, required by the weather and stage of operations. The trial demonstrated how bending stress and fatigue could be removed from a rigid system using ArticuLock. Stress tests, where adverse weather conditions were simulated, also were conducted to further demonstrate how the system would perform in such conditions.
Unproductive time, as a result of weather delays, costs the UKCS a staggering ￡400 million ($527.2 million) each year, approximately. A situation that was previously accepted as the nature of the job, more than 20% of a rig budget can end up being allocated to waiting on weather. The trials demonstrated how ArticuLock could extend the weather window for subsea tool deployment, and how it could contribute to improved certainty and safety around subsea tooling operations.
SEACURE–ENHANCING CEMENTING OPERATIONS
Cementing is a critical step in well construction, as it creates the seals required for the well to function efficiently, and to permanently prevent water migration into the wellbore annulus. Traditionally, cementing requires the use of shoe tracks and plugs, with pressure tests carried out on set cement to ensure the integrity of the cement job.
However, new technologies can greatly enhance the efficiency and integrity of cement jobs, which can deliver significant cost- and time-savings to operators, as well as reducing the risk of cement displacement and micro annulus formation, once the cement has set.
SeaCure, our flagship technology, is an innovative subsea cementing system, which delivers stabbed-in, inner-string cementing for subsea wells. Inner-string cementing involves a drill pipe being used inside the casing to cement a well; it is generally considered to be a more efficient technique, as it allows better control of cement displacement and fluid interfaces. The proprietary SeaCure system takes this process to the next level, and provides a range of major cost and time benefits to drilling and field development operations.
The technology’s potential to optimize drilling operations and save rig time has been recognized by major operators. Working with the OGTC, field trials were completed at an onshore test well, Fig. 3. The trials were attended by Chevron, Siccar Point and AGR, and demonstrated how the technology can increase the functionality and efficiency of cementing operations.
SeaCure can be deployed for operations involving surface conductors and casing strings. It also can potentially be used with drilling liners. Furthermore, the tool could be applied to dry tree cementing of any casing or liner string, where time is of the essence for the cement to set.
The first SeaCure job took place in September, where it was used to cement a 30-in. conductor casing for Chevron’s North Sea subsea appraisal well, West Wick, which was being drilled from the Ocean Guardian semisubmersible. With no shoe track present, SeaCure eliminated the need to perform a dedicated clean-out run, prior to drilling ahead with a 12?-in. bottomhole assembly (BHA) straight out of the 30-in. float shoe.
This technology is a completely mechanical system with no electronics or hydraulics, making it a robust and reliable technique for optimizing cement jobs and saving rig time. It eliminates the need for shoe tracks and round trips to clean them out, which can take several days to complete, especially in deep water. Furthermore, it improves cement placement, reduces displacement, facilitates offline casing pressure testing, and improves drill out performance by minimizing the risk of damage.
THE MECHANICS
SeaCure’s unique design uses a combination of standard industry components, such as a double non-return valve with wiper dart receiver and drill pipe latch-in receiver, which are used extensively in the oil field.
Latch-in float equipment is run on the bottom of the casing or liner, to be cemented with the first section of inner string containing the corresponding latch-in drill pipe adapter at the base, and a bespoke rupture disc port.
After the first section of inner string has been inserted, the inner string section of the SeaCure tool is connected, followed by the rest of the inner string, thereby making the system an integral part of the inner string, when deployed, Fig. 4. As the inner string and running tool are lowered and secured downhole, this action forces the tool to slide partially closed and into the free rotate position, which allows for safe engagement of the running tool.
This section of the tool is the most important part, as it makes the whole technique possible. Using a standard slip joint, it compensates length discrepancy between the casing and inner string. As well as providing a generous 10 ft of stroke, a clutch mechanism ensures safe engagement and disengagement of the rest of the casing system. This technique removes the need for large running tool seals, as rotary connections form the seals for currently performed cement jobs.
Once at cementing depth, cement is pumped into the casing through the inner string. The wiper dart is launched, followed by a small amount of slurry. When the wiper dart locks with the receiver at the base, the resulting pressure bursts the rupture discs, and the contents of the inner string can escape through the running tool, allowing for post-cementing circulation to start. Pressure tests can be conducted during this process, while the cement is still green, which eliminates the risk of micro-annulus development. These tests are critical to ensuring the integrity of the cement job, and that the SeaCure technique enhances cement seal integrity and reliability.
With the casing tests completed as part of the cementing process, the inner string and SeaCure tool can be recovered, allowing the next section to be drilled with no cement plugs or shoe track to damage the BHA or drill bit.
THE FUTURE OF DRILLING
Our technology is saving rig time by reducing costs, risk and unproductive time. Advances in drilling technology are paving the way for unlocking challenging reservoirs and achieving the industry-wide goal of maximizing economic recovery. The focus on technology, collaboration and people needs to be maintained, as all three are required to keep the industry moving forward. Collaboration is playing a huge part in the successful adoption of new technologies. For companies like ours, it has provided an opportunity to work alongside industry leaders and operators, which have played an active role in the development and acceptance of new technology.
New technology is providing intelligent solutions to address challenges and talented, skilled personnel, who understand the complexities of the industry, are essential to developing and designing the solutions that are needed to help the industry progress.
Enhancing operational efficiency will, forever, be a priority for the industry. Investment in drilling technologies is essential to continue delivering results and maximizing recovery into the future.
石油圈
