Advancement in Openhole Sand Control Applications Using Shape Memory Polymer

Abstract

Abstract This paper summarizes a game-changing technology using shape memory polymer (SMP) to provide downhole sand control in openhole environments. An openhole completion maximizes well productivity/injectivity and longevity without the concern of plugging and/or collapsing perforation tunnels that are frequent challenges in cased-hole completions. Conventional openhole sand control techniques include stand-alone-screen (SAS), expandable screens and openhole gravel packing (OHGP). In some cases, the uniformity, size and level of compressive strength of the formation dictate the use of an OHGP completion. This has proven to be a highly effective technique and eliminates the concerns of plugging and erosion associated with a SAS. However, an OHGP is not always feasible and/or practical for some reservoirs and geographic locations. Some of the challenges of OHGP include lack of deck space and equipment, incompatibility with annular zonal isolation tools, difficulty to gravel pack across shale zones, and unavailability of equipment or fluid design to effectively gravel pack extremely long laterals without exceeding reservoir fracture gradient. The SMP technology can fill the gaps that exist with current OHGP techniques. The performance of the SMP centers on its inherent glass transition property. It is run into the wellbore in its compacted state and then activated to expand to the openhole size at the target depth when exposed to a catalyst. Once expanded, the SMP conforms to the sandface including washouts and any irregularities within the SMP expansion limit. It is porous in both compacted and expanded states with permeability of over 30 Darcy after expansion. Its filtration capability is equivalent, if not superior, to that of an OHGP application. In this paper, the SMP’s "engineered" behavior and sand control mechanism will be introduced first, followed by the performance comparison between the SMP and conventional OHGP, activation fluid design and the operational procedures. The last section will be focused on the SMP operating envelopes.