In recent years, operators have reported that dissolvable frac plugs have made completions more time-consuming and costly in many cases. Poorly designed dissolvable frac plugs can cause problems such as early failure and skidding under pressure when they dissolve too early.
On the other hand, if dissolvable frac plugs do not dissolve completely, it can lead to extended post-intervention time. Drilling out a composite frac plug typically takes 2-15 minutes, while removing a dissolvable frac plug that hasn't dissolved fully can take up to an hour or even longer due to the material structure not being designed for quick drilling.
Additionally, when undissolved frac plugs are pushed towards the bottom of the well, they can create a pack-off on the way, which increases drill-out time. This is a common issue in low temperature and low salinity environments because temperature and salinity are two key factors that influence the dissolving process of dissolvable frac plugs.
Based on our experiences, dissolvable technology can be both beneficial and challenging. To customize products that are suitable for different conditions, expertise and a thorough understanding of both application and engineering are necessary. The tool supplier must consider all operational details, including the conditions and requirements, to design, simulate, validate, and optimize the product in order to achieve optimal performance and results for end users. This requires a careful balance between tool performance and dissolvability.