The Importance of Subsea Well Intervention: Exploring Its Vital Role in Offshore Operations

As the industry expands into deeper water and horizons that require horizontal well configurations, accessing all parts of a well requires advanced technologies. This is where subsea well intervention (SWI) comes in.

With day rates for rigs and dedicated well intervention vessels at their lowest levels in years, operators should use this opportunity to rethink their approach to SWI.

Well Abandonment

When a well’s oil or gas reserves dwindle or exploration efforts prove unsuccessful, it may be necessary to abandon the well. This is a crucial step that must be done correctly to avoid environmental contamination or damage to other marine structures. The process of well abandonment includes the following:

• Milling.
• Retrieving the casing.
• Setting barriers to isolate intermediate hydrocarbon or water-bearing permeable zones.
• Installing an environmental plug.

A thorough understanding of the well’s construction and site geology is key to successful abandonment. This information is critical for effective characterization and well-integrity evaluations.

Well-intervention services such as rigless well intervention are vital to offshore operations. They enable crews to monitor well health and improve productivity. These services can be performed on rigs or from dedicated vessels. 

Well Completion

The production of oil and gas from offshore wells involves some complex operations. One of the most important is the completion process, which involves installing the production equipment and securing the wellhead with safety valves.

While interventions in subsea trees share many similarities with those on land or platform wells, the complexities involved mean that errors can be much more costly. Moreover, the cost of a good outage can far exceed any productivity benefits gained from an intervention.

The downturn has presented a significant opportunity for rig owners, service providers, and vessel operators to understand the market and build long-term capability. Low day rates make it feasible to conduct SWI campaigns now, which would have been uneconomical in the past, providing valuable experience ahead of an anticipated recovery.

Well Repair

The shift to cleaner energy sources affects oil demand and, therefore, the well-intervention market. However, the industry’s commitment to reducing emissions drives innovation and collaboration. With day rates for rigs and dedicated well-intervention vessels at their lowest levels, it makes sense for operators to investigate the possibility of entering this market on a more concerted long-term basis. This could help them gain valuable experience and better position themselves for higher oil prices. Moreover, by deploying such tools, they could reduce operational costs.

Well Maintenance

Since the late 2000s, the subsea well intervention industry has been in a period of growth. However, it has struggled to catch up with the rapid development of mature fields and the massive gap in rig counts between offshore and onshore. Several factors have contributed to this situation, including the comparatively prohibitive cost of bringing in a drilling rig for an intervention. This has resulted in the vast majority of rig capacity being used on exploration and production drilling, leaving little available to perform interventions.