Collaboration Enhances Process Safety

Collaboration is increasingly critical to managing well construction risk. While technology produces remarkable results, the most significant gains in well-bore construction process safety are being achieved across traditional disciplines, products, and services.

Bringing drilling contractors, manufacturers, and service companies into the well planning process at an early stage captures resources that are rich in expertise and technology and orients them toward the overall objective of constructing a high-integrity well bore to total depth (TD). While this is not novel, it is ever more imperative to ensuring project success.

In difficult wells, process safety is a major consideration to the execution of well construction. Subsurface conditions in these wells are pushing traditional technologies and work processes to their limits. Delivering discrete technologies and siloed services can be limiting and potentially hinder success.

Technologies such as closed-loop drilling (CLD) and drilling-with-casing (DwC) are information-intense and cross-discipline by nature. They require a new level of industry collaboration and engagement.

Finding new answers

There is a significant difference between being asked to run 457 m (1,500 ft) of 13 3/ 8 -in. casing in the hole and in helping mitigate hazards and ensuring wellbore integrity to TD. That difference changes the relationship from a “call-out” service to a collaborative partnership with a shared measure of success.

Greater alignment with the success of the project leads all parties to engage in collaborative risk assessment within the context of the operational envelope. The earlier in the project cycle this collaboration occurs, the greater the degree to which the outcome can be positively influenced. By collaborating, operators and service companies are in a much better position to understand, anticipate, and mitigate risk as well as reduce costs.

In particular, this collaboration taps into the strengths of integrated service companies. In addition to novel technologies, these organizations provide important new perspectives and experiences. Cross-discipline experts and engineering assets encourage a high degree of interaction within these services and with the operator. This collaboration is the vehicle for identifying new options and arriving at new solutions for enhancing process safety throughout wellbore construction.

Closed loop enhances well control

Process safety contains many elements, not the least of which is maintaining well control through the well construction process. Well control involves understanding and managing wellbore dynamics such as pore pressure and fracture gradients while drilling with the intent to eliminate or mitigate well control events and anomalies.

Traditionally, well control has largely been the province of mud systems and BOPs. But these methods alone are increasingly insufficient to manage HP/HT wells and narrow pore-pressure/fracture gradient windows. The repercussions are well control incidents and the inability to execute planned well designs that reach TD with the optimal hole size.

The leading edge of enhancing primary well control is a set of scalable CLD technologies. These systems, which include various managed pressure drilling (MPD) methods, use a novel fluid circulating system to achieve a major advance in wellbore monitoring and control. The advances are having a step-change effect on enhancing the protection of people, the environment, and assets. Less time spent fighting well problems also can result in a significant reduction of costs.

Collaboration with the operator early in the planning process is imperative to successful CLD applications. The importance lies in the fact that CLD applications must be engineered according to subsurface factors such as lithology, pressures, and temperatures. The planning process also facilitates training of operator and rig personnel on various closed-loop methods. Planning also helps anticipate modifications to deepwater rigs, which may involve changes to riser systems and deck accommodations. This type of collaboration already is impacting new rig designs that anticipate closed-loop configurations.

Total depth collaboration

Another critical element to process safety is wellbore integrity. From a tubular running and casing drilling perspective, collaboration is fundamental to the well construction process. This leads to novel hazard mitigation methodologies that integrate advanced tubular running service capabilities on the rig floor with extensive subsurface expertise and capabilities.

A congruous approach to planning and service delivery throughout the well construction process results in stronger defenses. Early collaboration is imperative to minimize the risk of an incident escalating into a catastrophic event.

Multidisciplinary service company engineers provide a common interface with the operator to identify, understand , and mitigate subsurface hazards. This in-depth engineering expertise is essential to developing a clear understanding of operator objectives. These engineers engage a broad scope of in-house specialists to help define potential wellbore problems and recommend appropriate methods and ancillary technologies within the context of constructing a high-integrity well bore to the planned objective.

This collaborative process guides the application of DwC technology, which enables rotation, reciprocation, and circulation while drilling with the casingstring. An inherent advantage to process safety is the ability to isolate trouble zones such as lost circulation or over-pressured zones behind-pipe while drilling and casing the well.

In addition, the ability to reciprocate the pipe during cementation results in better cement placement that enhances zonal isolation. This not only improves long-term wellbore integrity but also aides in preventing well control issues that could result in a blowout.

The ability to rotate and circulate casing in a predrilled section helps ensure that casingstrings are landed at the target depth, which also helps ensure that wellbore construction remains true to the optimal design. Among the benefits is the reduction of long openhole exposure times achieved by eliminating drillpipe tripping.

Building integrated solutions

While the scope of services involved vary greatly, collaboration provides the starting point from which the operator and service company explore well construction options and innovate solutions. An example is a recent project in Latin America. A major operator was planning reentry wells to reach reserves below a depleted zone. The operator was exploring options and asked Weatherford about DwC services. As engineers began to explore the operator’s objectives and challenges, the collaborative process greatly increased the options under consideration.

Ultimately it was concluded that DwC was not the optimal solution for drilling the depleted zone. But because project parameters were better understood, engineers were able to recommend other better-suited options.

The success of the effort clearly illustrates that if operators are to benefit from consideration of all the options, service companies should be brought into the loop early in the planning stages.

The collaborative path ahead

As the industry continues to drill more difficult wells, the risks associated with hazards become substantially higher, placing process safety as the paramount consideration. The result is a growing need for collaboration. By involving service companies in the planning process, operators enhance the integration of technology and accelerate its adoption, help drive efficiencies and productivity, and promote cross-organizational collaboration. These advances are central to enhancing process safety and achieving wellbore construction objectives in the most challenging applications.