Metal-Formed Liner Hanger Avoids High-Setting-Pressure Requirements

Abstract

Seminole Services announced the commercialization of its first product, the Powerscrew Liner System, a new expandable-liner hanger that is set with torsional energy from the topdrive (Fig. 1). The Louisiana-based company began development on the tool and associated equipment in the fall of 2012. Rooted in solid mechanics and material science, the company provides engineered wellbore solutions to exploration and production companies actively engaged in drilling oil and gas wells. In the evolution of liner hangers, mechanically set systems were developed first. While many operators believe mechanical systems are more robust and provide superior sealing integrity when compared with hydraulically set hangers, older mechanical systems typically lack reliability, especially in applications requiring longer liners in deviated wellbores. In large part, this is because of the risks associated with reaming a mechanical hanger to setting depth. Reliability rates were increased with the introduction of hydraulically set hangers, which allowed a greater range of applications. However, the newer setting method suffers from its own limitations, such as flow-area restrictions, compatibility with drilling-fluid additives, and a multitude of potential leak paths. With the advent of expandable-liner hangers, further increases in setting reliability were achieved along with even greater applications. The increase in reliability stemmed, at least in part, from greater success reaming the liner to setting depth. The higher reliability of expandables is perhaps a consequence of greater flow area at the liner top and the lack of external setting devices. This has led to many new developments in drilling with liners (DWL). Nevertheless, expandable-liner hangers continue to suffer from potential leak paths associated with high hydraulic pressure sourced at the mud pumps. The hydraulic pressure provides energy to the running tool necessary in setting the liner top. In most expandable systems, pressure pushes the roller/ expansion cones/sleeve through a metal-formed tubular by use of a multitude of pressurized connections and fluid ports. By contrast, the torsionally set system combines the latest in metal-forming technology along with the best features of mechanically set systems. The result is a setting process that does not require high hydraulic pressures and eliminates the risks associated with reaming the liner to setting depth and DWL.