The accelerated decline rates of tight unconventional reservoirs have intensified a surge in refracturing programs. Operators are taking advantage of improved fracturing designs to increase production and estimated ultimate recoveries of largely impermeable shale wells. Enventure introduced a series of expandable liners, including the ESeal refracturing liner, that provides zonal isolation in higher-temperature environments in order to extend the safe operating window. Operators have achieved production increases with solid expandable technology after refracturing liners have been installed, compared with production before the refracturing. The enhanced expandable refracturing liner provides 16% more tensile strength to allow installations in the 225°F–250°F range. The high-temperature refracturing liner provides 40% more strength to allow installation in the 300°F range. Pairing this offering with its proprietary engineered liner analysis, the company can assist operators in making data-based decisions about their refracturing options. Two successful field installations using the new expandable liners have been completed. The first installation occurred in south Texas. 5,000 ft of 4¼-in. expandable liner was installed and expanded inside 5½-in. casing at a bottomhole temperature of 230°F. A second 450-ft installation occurred in west Texas, also inside 5½ in. casing at a bottomhole temperature of 165°F. Both were installed, pressure-tested, and fractured with no indication of pressure loss.
The next generation of expandable zonal isolation products from Enventure
Today’s refracturing challenges require solutions that provide maximum results while managing predictable production results. Enventure’s next-generation Refrac System does both. More than two decades of experience and client collaboration have given us the edge in developing an expandable zonal isolation system that provides
- Customized refrac isolation solution
- Largest inside diameter (ID) possible
- More flow and power to the reservoir
- Permanent solutions to zonal isolation.
- Ability to operate in higher temperature reservoirs
ESeal system of mechanical diverters
Enventure’s ESeal 3.0 Refrac System employs solid expandable mechanical diverters. Each is designed to provide refracturing solutions in specific well environments. All effectively create a new wellbore with the maximum ID (inside diameter) for the isolation of existing perforations, thereby providing more flow to your reservoir. This helps you have more power for your refrac – to get a better frac and increased flow area for production afterwards.
Designed to meet your specific refracturing needs
The ESeal 3.0 RF and RF-HT deliver higher pressure integrity by optimizing the expansion process. Both use our Engineered Liner Analysis service.
ESeal 3.0 RF – Our next level system utilizes newly enhanced connections that are 16% stronger than the previous generation and are ideal for vertical and horizontal wells in less extreme temperature environments.
ESeal 3.0 RF-HT – Our highest rated system, the ESeal 3.0 RF-HT (High Temp) Refrac Liner, uses the toughest connections in the industry: 40% stronger than the previous generation.
Liner Analysis Service
Thanks to continuous feedback from our clients, Enventure now offers a powerful service to calculate the safe operating window for your refrac using any solid mechanical diversion technique. Our Engineered Liner Analysis will allow you to balance cost vs. frac effectiveness and production rates. That analysis will help determine the most effective approach to refracturing.
Considerations in the Liner Analysis
The Liner Analysis estimates tension in the liner for different plug locations by considering the possible ranges of Treatment pressure, downhole temperature, frac fluid density and reservoir pressure and then comparing that to connection ratings to determine feasibility of fracturing solutions. Enventure will walk you through the factors and scenarios that significantly affect the loads or provide the considerations for you to compare with your own internal models.
Benefits to Asset Managers
Regardless of oil prices, you need predictable costs and reliable results when refracturing. Enventure’s next generation Refrac System delivers this by improving upon previous mechanical diversion techniques, which already have the highest success rate and reliability in the industry. Pairing this with our Engineered Liner Analysis service, you can make data-based decisions about your refrac options and choose the most cost effective option from our tiered system.
Benefits to Operators
Today’s oilfield operations are a constant balancing act. You need to optimize ROI and minimize risk during multi-zone isolation and recompletion operations, while balancing cost vs. frac effectiveness and production rates. Now you can make this balancing act easier with Enventure’s comprehensive Refrac System. Efficient and cost-effective options will enable you to mechanically isolate old perforations to provide internal pressure integrity and zonal isolation, with largest ID possible, providing more flow and more power to your reservoir.
ESeal™ Refrac Liner Provides 47% Greater Flow Area Vs. Conventional Recompletion
A major Operator in the Barnett Shale needed to isolate four depleted perforation clusters to successfully refrac their well. The operator required a solution that would provide predictability and accuracy that chemical diversion had not been able to provide. Completing the well with a 4 in. flush-joint conventional liner would restrict ID, resulting in insufficient frac rates for the planned refrac program and increase costs for the additional hydraulic horsepower required.
The ESeal RF Liner increased flow area by 47%, compared to the conventional recompletion option. Ten expandable seals placed along the liner, ensured accurate isolation of old perfs, enabling the operator to effectively apply lessons learned for an optimal refrac program with a new wellbore. The ability to refrac into new reservoir rock proved the ESeal RF Liner as “The Ultimate Diverter™.” Surface pressures during the refrac were identical to those during the initial frac, indicating that the ESeal RF Liner enabled the operator to fracture into new, untouched reservoir.