Rapid Cure System for Nutplate Installation

Air Force platforms utilize nutplates to attach components when fasteners access is limited. Damaged nutplates require timely replacement and approved repair techniques mandate the use of certified adhesives, typically requiring a lengthy 24 hour cure at room temperature. Therefore, Air Force repair depots are faced with the difficult situation of performing high volume, timely nutplate repairs using materials initially optimized for long working time. Adhesive cure can be accelerated with the application of supplemental heating, but improper heating effects material properties and reduces nutplate performance. Cornerstone Research Group, Inc. (CRG) proposes to develop an accelerated adhesive cure cycle and localized, controlled heating system capable of maintaining nutplate performance in restrictive repair environments (e.g. on-aircraft). During Phase I, CRG developed accelerated cure profiles and a rapid heating system leveraging commercially available components. Functional nutplate repairs were performed in a lab environment and demonstrated feasibility of the rapid cure system. Phase II will result in optimization of accelerated cure profiles and a fabrication of a refined rapid cure system addressing on-aircraft safety requirements. The improved system will be evaluated through on-aircraft repair. Phase III will focus on transitioning the technology to Air Force repair depots and commercialization of the rapid cure system.