Welltec® Light Packer prevents sustained casing pressure and methane emissions in the US

Challenge
Well construction & integrity
Sub Standard Graphics 3D JUSCO213715 00000
  • Well type Unconventional oil producers
  • Depth ~7,000 ft (2134 m) TVD; ~16,000 ft (4877 m) MD inc

Background

In the DJ Basin, Colorado, an operator faced a persistent challenge with Sustained Casing Pressure (SCP) in approximately 30% of unconventional oil production wells targeting shale formations. The SCP issues encountered by these crucial wells were hampering hydraulic fracturing operations due to stringent local regulations.

Compliance required SCP remediation to bring pressures below 200 psi at the surface. The SCP issue not only incurred an average remediation cost of $300,000 USD per well but also posed a risk of methane emissions due to compromised casing integrity.

Solution

Despite attempts with various remedial and preventative options, the operator sought an innovative solution. In close collaboration with Welltec®, the operator deployed the 812 Welltec® Light Packer XL (812WLP XL) as a preventative measure to address SCP.

This solution aimed not only to safeguard well integrity but also to prevent potential methane emissions associated with casing degradation.

Operation

Outfitted with a unique and proprietary valve block system, the 812WLP XL was tailored for the operation meaning that full integrity of the casing remained intact post-expansion. To date, almost 300 separate WLPs have been deployed demonstrating the flexibility and effectiveness of the solution and the efficiency of Welltec's delivery process.

In a typical deployment, positioned at approximately 2,900 ft in non-permeable shale, each WLP was floated in hole as part of the production casing string to TD, with the WLP placed at approximately 2,900 ft (884 m) MD in non-permeable, competent shale where the hole is approximately deviated by 14°. During cementing operations, the WLP was expanded via 5,500 psi of pressure, conforming to the borehole. This method allowed for rapid deployment and expansion, minimizing operational disruption and potential methane emissions associated with SCP.

The WLP solution, chosen for its proven track record globally and metal-to-rock contact capability, was presented to local regulators, receiving positive feedback.

Achievements

Following deployment of a WLP solution in 24 wells, SCP at the surface was completely eradicated, also signaling zero methane emissions from the well. The operator realized significant savings of approximately $1.4 million USD across the 24 wells, showcasing the success of the operation. Beyond cost savings, preventing SCP ensured hydraulic fracturing operations could proceed on schedule.

The WLP solution provided an immediate, efficient, and technically robust alternative compared to other trialed methods. Its ability to be rapidly expanded post-deployment, without the need for separate wireline runs or extended activation periods, made it a preferred choice. Buoyed by this success, the operator committed to ordering WLPs for all remaining planned wells in 2022, underscoring the reliability and efficiency the solution brought to their operations.

Nick Rakic, Solutions Director

“The WLP is a robustly engineered solution, qualified using the most stringent qualification standard that has enabled my client to deliver wells faster and safer, while realizing significant savings. Going forward, I believe this should be the standard in well construction to ensure more efficient operations and cleaner world for future generations.”

Well schematics

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